International Training Programme for Cambodian Trainees

On

Freshwater Fish Seed Production and Nursery

Rearing in West Bengal, India

5th to 10th November, 2012

Faculty of Fishery Sciences

West Bengal University of Animal and Fishery Sciences, Kolkata,

India

TRAINING COMPENDIUM

Published by:

Prof. K.C.Dora

Dean, Faculty of Fishery Sciences,West Bengal

University of Animal & Fishery Sciences

Edited By: Prof. R.K.Trivedi

Dr. B.K.Chand

Mr. Sourabh Kumar Dubey

Publication date: 10th

November, 2012

Printed By: Dutta Printers, Jadavpur, Kolkata - 700032

Organizing committee

Prof. K. C. Dora Chairman

Prof. R. K. Trivedi Course Coordinator

Prof. S. S. Dana Member

Dr. T. K. Ghosh Member

Dr. G. Dash Member

Dr. S.K. Rout Member

Mr. S. Choudhury Member

WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES

68, Kshudiram Bose Sarani, Belgachia,

Kolkata - 700 037, West Bengal, India

Prof. C.S.Chakrabarti

FOREWORD

Historically, India has very warm and cordial relationship with Cambodia. The pervading

influence of Hinduism, Buddhism, and Indian architecture, is borne out by the structures at

Angkor Wat, Angkor Thom, Bayon, Baphuon, and other religious and historical sites in

Cambodia. This is the glorious testimony of profound cultural and social basis of India-

Cambodia historical relationship. In 2010, when the former President of India Smt. Pratibha Patil

visited Cambodia, she had emphasized on greater cooperation between two countries to access

knowledge, expertise, resources and markets for the development. Human resource development

and capacity building have been the primary focus of our bilateral relations and the present

training programme on aquaculture for the Cambodian fish farmers is a small step in this

direction.

Aquatic resources of India are vast and diversified. Replenishment and creation of water bodies

through Southwest and Northeast monsoon in India are nature’s gifts. The success in induced

breeding of carp in 1957 and subsequent technologies on induced breeding and seed rearing for a

number of species, paved the way for the revolution in fish production through aquaculture. At

present, India is the second-largest aquaculture producer in the world and about 80% of India's

aquaculture production is composed of carps. Many states of India have both inland and marine

aquaculture opportunities and potentialities. Farmers from Cambodia may get some ideas at least

about the inland fisheries especially in the sector of seed production through this training

programme.

I am hopeful that the training programme will help Cambodian trainees to have the glimpse of

Indian aquaculture and gain advance knowledge and skill on scientific aquaculture. The

compendium comprising good numbers of resourceful writing will be very useful to the trainees.

I thankfully acknowledge the endeavour of all concerns, including the Governments of India and

Cambodia.

Kolkata (Prof. C S Chakrabarti)

10th

November, 2012 Vice Chancellor

FACULTY OF FISHERY SCIENCES WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES

5, Budherhat Road, Chakgaria, P.O:- Panchasayar,

Kolkata -700 094, West Bengal, India

(H.Q: 68, Kshudiram Bose Sarani, Belgachia, Kolkata - 700 037)

E-mail: kc_dora@yahoo.co.in Ph: 9433368328 TeleFax: 033 2432-8749

Prof. K. C. DORA

DEAN

PREFACE

Aquaculture sector plays a vital role in the socioeconomic development of India and

recognized as a powerful income and employment generator as it stimulates the growth of a

number of subsidiary industries and is a cheap nutritious food besides being a foreign exchange

earner. It is the fast growing sector with annual growth of more than 6% in last two decades. This

has been possible by vertical and horizontal expansion of area under farming and use of intensive

and modern aquaculture practices involving higher use of inputs. India is the second largest

producer of aquaculture products after China. West Bengal is the highest fish producing state in

India with highest percentage of fish consuming population in the country. Apart from this, West

Bengal is the pioneer and leader in fish seed production in India. In the year 2010-11 West

Bengal produced 13453 million of fish seed, contributing about 62% of the total production of

fish seed in the country. In the same year West Bengal produced 1.443 million Metric Ton fish.

Both the Indian major carps and Chinese carps are found to be well suited for rearing in fresh

water ponds. Among many fish farming practices, the composite fish culture is one, which

common farmers of India easily adopt with comparatively less investment to have more

production and income than the traditional farming practice.

It is a pleasure that the Faculty of Fishery Sciences, West Bengal University of Animal &

Fishery Sciences is organizing an International Training cum Exposure visit for Cambodian fish

farmers and fishery official during 5th

to 10th

November, 2012 in collaboration with Asian

Fishery Society-Indian Branch. I wish the training programme all success and hope to be

beneficial for the Cambodian delegates.

Kolkata (K. C. Dora)

10th

November, 2012

FACULTY OF FISHERY SCIENCES WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES

5, Budherhat Road, Chakgaria, P.O:- Panchasayar,

Kolkata -700 094, West Bengal, India

(H.Q: 68, Kshudiram Bose Sarani, Belgachia, Kolkata - 700 037)

E-mail: ramankumart@rediffmail.com

Prof. R.K. Trivedi

ACKNOWLEDGEMENT

It is my great privilege to get associated as Course-Coordinator for organizing International

Training cum Exposure visit for Cambodian fish farmers and fishery official on a topic of current

importance “Freshwater Fish Seed Production and Nursery Rearing in West Bengal, India”

during 5th

to 10th

November, 2012 which is highly need based constituting one of the most

important components of today’s commercial aquaculture pursuits. With excellent support and

encouragement by the Prof. C. S. Chakrabarti, Vice Chancellor of this University, Prof. P.

Biswas, Registrar, and Dean of Faculty of Fishery Sciences, Prof. K.C. Dora, I have tried to

structure the training programme in a benefiting manner taking due care of making it effective

and successful. I wish to place my utmost gratitude to Mr. M.C. Nandeesha, Chairman, Asian

Fisheries Society Indian Branch and Ministry of Agriculture, Govt. of India. I express sincere

thanks to JICA and specially Mr. M. Sato for taking initiative for this exposure visit. I am highly

thankful to our faculty teachers namely Dr. G. Dash, Dr. T. K. Ghosh, Dr. S. K Rout, Prof. S. S.

Dana, Prof. T. J. Abraham and others to extend all possible support. I would like to express my

heartfelt thanks to Dr. B. K. Chand and Mr. S.K. Dubey for assisting me in preparing the

Training Compendium and giving me valuable inputs in successful completion of the

programme. I am also thankful to Prof. A.P.Sharma, Director, CIFRI Barrackpoe, Dr. B.K.

Mahapatra, Principal Scientist, CIFE Kolkata Centre, Dr. S. N. Biswas, Deputy Director,

Department of Fishery, Govt. of West Bengal, Mr. B. Halder, ADF, Fishery, S 24Pgs for their

unstained support. I would also like to thank the other training associates for their whole-hearted

co-operations. Last but not the list, I am greatly indebted to all the fish farmers and fishery

entrepreneurs cover during exposure visit for their volunteered

disclosure in making this programme grand success.

Kolkata (R.K.Trivedi)

10th

November, 2012 Course Co-ordinator

INDEX

Sl. No Topic Contributor Page No.

1 Seasonally Flooded Water Bodies – A

Potential Resource for Rice-Fish

Farming in West Bengal, India

Utpal Bhaumik and A.P.Sharma

1

2 Status of Ornamental Fisheries in West

Bengal, India B.K. Mahapatra

18

3 Nursery Rearing of Carp Fry &

Fingerlings and Grow-Out Carp Culture

with Special Emphasis on Pond

Management

R.K. Trivedi , S. K. Dubey

&

S. K. Rout

38

4 Breeding and Larval Rearing of

Pangasius Sutchi

N.R. Chattopadhyay

45

5 Status of Fish Diseases in West Bengal

Dr Gadadhar Dash

50

6 Nursery and Rearing Pond Management Dr. S. K. Das 68

7 Culture of Indian Major Carps and

Exotic Carps

Dr. T. K. Ghosh

74

8 Tilapia Farming in India Dr. B K Chand 91

9 Sewage Fed Fish Culture Practices in

East Kolkata Wetland

S. K. Dubey & R. K. Trivedi

100

10 Favorable Ranges of Water and Soil

Quality Parameters for Fish Farming

and Hatchery operation

S. K. Dubey & R. K. Trivedi

107

11 Present status of Fisheries in West

Bengal (Presentation)

Dr. Goutam Chandra Sarkar Annex

I

12 Photo sheet of training

Annex

II

13 Training schedule

Annex

III

14 List of participants

Annex

IV

Training Compendium

1

SEASONALLY FLOODED WATER BODIES – A POTENTIAL RESOURCE

FOR RICE-FISH FARMING IN WEST BENGAL, INDIA

Utpal Bhaumik* and A.P.Sharma

Central Inland Fisheries Research Institute

Barrckpore, Kolkata- 700120

*email: utpal_bhaumik@yahoo.com

Water is most precious natural resource and is indispensable for all economic and

social development and ending poverty and hunger. Past two decades have been growing

recognition of crisis facing the country‟s water resources and the need for concerted action

to use these more efficiently. The efficiency of water use or water productivity can be

increased by producing more output per unit of water used, or by reducing water losses, or

by a combination of both. So far, strategies for increasing output have been limited to crop

only. Water productivity at several organisational levels can be increased by integrating

fish and rice/other aquatic resources into the existing water use systems. Such opportunities

of integration include community based rice-fish culture in seasonal floodplains.

Both rice and fish are immensely important to the livelihoods of the rural poor in

India especially in West Bengal as both a source of nutrition and as a source of income

(Bhaumik et. al.2005). Rice and fish are considered to be the two main sources of food in

this region. It has been estimated that rice constitutes as much as 60% of the daily food

intake of the majority of Asians. Rice consumption in West Bengal, India is reported to be

139.68 kg/ head/ year and 127.56 kg /head/year (1993-1994) in rural and urban areas of

India respectively (Saha and Bardhan Roy, 2001).

According to World Fish Centre (2002) over 10 million ha or 15 percent of the total

rice land in Asia suffer from uncountable seasonal flooding of which over half are in Indian

subcontinent mainly in Eastern India and Bangladesh. These areas are the habitats of

millions of farmers, landless populace living with low profile socio-economic conditions

Training Compendium

2

(Ali, 1990). Because of the plentiful rainfall during the monsoon from June to September,

rice becomes the principal crop in West Bengal, India from this time. Waterlogged rice

fields are the ideal natural habitat of various types of fish (Nguyen, S.H. et al., 2001). Some

workers have expressed that fish in rice field results in an increased yield of grain varying

from 4 – 10 percent. Further, it has been found that fish consume large quantities of weed,

worms, insects, larvae and algae, which are either directly or indirectly injurious to rice

(Datta et al, 1985).

Fish is widely consumed in the country, certainly in West Bengal where per capita

consumption is estimated to be 15.6 kg in comparison to Indian rate of 9.0 kg. It is

considered to be the major source of animal protein for the majority of people in West

Bengal and a major source of vital micro-nutrients (Govt. of West Bengal 2009).

Freshwater fish, because of its relatively low price, represents a vital source of animal

protein for lower income groups especially in West Bengal where it is estimated that about

94% of farmers may be classed as poor.

Rao and Singh (1998) have estimated that of the 42 million hectares of rice

cultivated land in India, about 20 million hectares is suitable for rice-fish integration while

Shyam (1998) estimates that only 0.23 million hectares is currently being managed as rice-

fish systems. Floodplain areas provide a predominantly freshwater environment for the

culture of rice and freshwater fish and prawns (floodplain wetland 0.04 million ha). In

addition, it is estimated that in West Bengal, alone there is a total brackish water area of

405,000 hectares, a significant proportion of which could be suitable for fish/shrimp culture

or the culture of fish/shrimp and saline tolerant rice varieties.

Vast areas of rice in eastern India are still non-irrigated and chiefly mono-cropped

producing only one crop of wet season rice in a year. Deep Water Rice (DWR) area is such

an area which covers about 11 per cent of the total rice land in India. Crop intensification

has proved now as the best tool for increasing food production which is badly needed to

keep pace with exponentially growing human population. Since, there is little scope for

Training Compendium

3

horizontal land expansion, its vertical expansion through integrated farming in single land

area has become the obvious alternative and since, rice and fish area important dietary

component of Indian populace, integration of rice-fish system will offer possibilities of

increasing land productivity. Thus, natural long time water logging less productive rice area

offers an ideal situation to be explored intensively for development and improvement of

rice - fish system. The scope-increased production in flood-prone ecosystem is the

integration of fish culture with rice farming. The flood prone areas are seasonally flooded

during the monsoon and remain submerged for 4 – 6 months. The vast water-bodies can

provide natural habitats for various aquatic resources including wild fishes and prawns. The

yearly silt deposition and organic matter decomposition catalyse the natural growth of flora

and fauna. The abundance of such natural fish food organization favours fish culture for 4 –

6 months in these areas.

Apart from the seasonally flooded freshwater rice fields, high rain fed areas along

the coastline are also used for monsoon rice cultivation, which are mono-cropped. During

the rest of the year, these usually remain fallow due to high salt content of the soil

associated with non-availability of irrigation water. Rice-fish culture in coastal saline areas

aims at utilizing the summer fallow period of these plots through short duration brackish

water aquaculture in sequential system without affecting the subsequent rice crop in the

same plot during monsoon. The population inhabiting in the flood-prone areas are basically

poor. Increased food production from rice-fish farming in these areas could play a vital role

in reducing malnutrition increasing household income and promoting food security.

Enhancement of rice-fish systems, through stocking, can increase overall yields and

substantially increase income from the system and, where fish is cultured alongside rice,

the rice yields can be improved (Saha & Bardhan Roy et al. 2001 and Bhaumik et al.,

2005). Enhancement provides an opportunity to increase the income generated from the

system and provides fish for household consumption. Rice-fish culture in India has been

practiced for almost 1500 years and has developed from low input systems to become more

intensive (Ali, 1990). However, in many cases the integration of fish with rice farming has

Training Compendium

4

been constrained by both technical and institutional factors (Mohanty et al. 2004).

Experience has suggested that, while enhancements have the potential to yield substantial

benefits, the actual outcomes (in terms of yield, distribution of benefits and institutional

stability amongst others) are often different to those initially expected. It is often said that

the results from field trials are less than those of experimental trials (Mohanty et al. 2002).

The underlying reason for these unexpected outcomes is uncertainty about the resource

systems. This uncertainty manifests itself as (a) limited prior knowledge of local conditions

and (b) the complexity of environments into which enhancements are introduced.

In flood prone areas, land ownership remains with cultivators who produce rice crop

(Summer crop) during the dry season whereas during wet season individual land holdings

are not visible and it takes the shape of vast sheet of water. Fish available in such water

bodies become a community property favoring access to all members of a local community.

Thus, it is likely that poor members of community belong to respective local areas will

manage common property resources sustainably which they have effective control.

Therefore, it is essential that the rural community with group management or with suitable

beneficial institutional approach need undertake rice-fish culture in the flood prone

ecosystem. Resource management approaches, viz. integrated resource management and

ecosystem based planning are essential for the sustainable use of natural resources.

Bhaumik et. al. 2005 facilitated community-based management approach successfully to

achieve both socio-economic and ecological objectives through integrated conservation –

developing planning. Community based management also indulges a mechanism for

economic development by participation of all categories of resource users and the

community members actively solve problems and address needs.

Seasonal flood plain resources for rice-fish farming

The state of West Bengal is bestowed with bountiful natural resources. Since time

immemorial Rice and fish farming formed an important livelihood component to millions

Training Compendium

5

of farmers of the State. West Bengal is situated in a latitude 21038”N – 27010”N and

longitude 85038”E – 89050”E with a total area of 88551 square kilometers associated with

the floodplains of the mighty rivers namely the Ganges, Damodar, Rupnarayan, Kansabati,

Haldi, Mayurakshi, Subarnarekha, Silabati, Ichamati, Churni, Mahananda, Teesta, Torsa,

Ajoy, Jalangi, Bidyadhari etc. The Bay of Bengal bounds 750 kms coastline in South.

Table1. Estimated area under deep water ecosystem in different floodplains of West

Bengal

Flood Plains District Area

(million ha.)

Share of total deep

water ecosystem (%)

Teesta Mahananda

flood plain

Coochbehar, North Dinajpur

& Northern part of Malda

0.028 4.60

Gangetic flood

plain

Murshidabad, Nadia and

Hooghly

0.185 30.83

Damodar

Kangshabati

floodplain

Midnapore & Birbhum 0.102 17.00

Costal flood plain 24-Parganas (N&S) &

Howrah

0.284 45.57

Total 0.599 100.00

(Source: Saha & Bardhan Roy, 2001)

The seasonally flooded deepwater rice area in West Bengal is approximately 0.6

million ha (Table 1). These areas are basins of saucer shaped where rain or flood water

accumulates during monsoon. Apart from this, coastal wetlands utilized commercially for

fin and shell fish production, can also be brought under rice-fish cropping system. The

seasonally flooded deep water ecosystem in West Bengal is spread over in different river

floodplains can be grouped as below:

a) Gangetic floodplains cover the deep water areas of Murshidabad, Nadia and Hooghly

districts having 0.185 million ha. (30.83 percent of the total seasonally flooded deep

water area);

b) Teesta – Mahananda floodplains covering the districts of Coochbehar, North Dinajpur

and northern part of Malda having 0.028 million ha. deep water area which constitute

4.60 percent of the total seasonally flooded deep water rice lands; Damodar-

Training Compendium

6

Kanksabati floodplains cover the districts of Midnapore and Birbhum with a total area

of 0.102 million ha. (17 percent of the total seasonally flooded deep water area); and

c) Coastal floodplains covering the saline areas in the districts of South and North 24–

Parganas and Howrah with a total area of 0.284 million ha. (47.57 percent of the total

seasonally flooded deep water area).

The traditional tall Indian deep water rice varieties are generally grown in these areas

during wet season in varying water depth. However, due to unpredictable nature of

flooding, these varieties generally contribute very low grain yield (1.5 – 2.2 t/ha.) (Table 2).

Table 2. Performance of major traditional floating rice varieties in the coastal Rice-

fish areas in West Bengal

Location Varieties Average

yield (t/ha)

24 Pgs (S) Bakui, Agniban, Sadamota, Malabati, Ramsail,

Benemuti, Baneswar, Dudeswar, and Marishal

1.8

Midnapore

(E)

Panikalash, Kakuria, Agniban, American queen,

Bakui, Bhuta, Goda Bhutia, Kammoth, Amol selat

and Hatipajra

1.5

24 Pgs (N) Mota, Sadamota, Hamai, Kumargore, Patnai 23,

Gerimuri, Boirbal and Kamini

2.2

(Source: Saha & Bardhan Roy, 2001)

Presently West Bengal being a major fish consuming state requires 1.6 million MT

of fishes annually (2009 - 2010) to meet the demand of 80 million population (Population

Census, India, 2001). However, the present availability of fish is 1.4 million MT (2009 -

2010). The little shortfall of requirement is met through import of fish from other Indian

States. A huge quantity of fin and shell fish (3.36 million MT) worth Rupees 720.00

million are also exported from West Bengal. Since the demand of fish in domestic and

export market is more, increase in fish production by utilizing natural resources is

considered to be a way to earn better economic return as well as protein supplement to the

population. Mixed cropping of rice and fish in these fragile ecosystems may contribute

better economic return.

Training Compendium

7

Meteorological status:

Climate condition of East Medinipore, Hooghly, Burdwan and North 24 Parganas districts

where seasonally flooded water bodies exist, are tropical, characterised of hot summer,

medium monsoon and mild winter season. Summer season starts from mid February and

extends still May. The period from June to September is the monsoon period followed by

winter season, which starts from November and continues up to February.

Moyna - the gold mine for rice-fish farming in seasonally flooded waterbodies

The block Moyna comprised of 84 villages is in Purba Midnapore district of West

Bengal. Vast seasonally flooded areas of Moyna are ideal for rice-fish farming. Moyna is a

block located in Latitute 22º40‟N and Longitude 87º50‟E under East Midnapore District,

West Bengal, India. It is one of the backward areas in West Bengal where the population

belong to poor category and agriculture is their primary occupation. Moyna block can be

divided into three potential zones in relevance to rice-fish farming namely Northern Zone

consisting the Gram Panchayat Gokulnagar, Paramanandapur and Tilkhoja; South Western

Zone having the Gram Panchayat Ramchak and Bakcha and the South Eastern Zone

consisting the Gram Panchayat Gijina, Naichanpur-I, Naichanpur-II, Moyna-I, Moyna-II. A

total off 5282 ha area is utilised for rice-fish farming operation. The following Mouza wise

operational areas are depicted in the tables 3-5:

Table 3. Potential seasonally flooded water bodies under Northern Zone

Name of field Mouza No. of water bodies Gram

Panchayat

Area

(Ha)

Uttar Anukha Uttar Anukha 02 Tilkhoja 126

Banki Banki 02 Tilkhoja 61

Banki

Bhandarchak

Tilkhoja 04 Tilkhoja 170

Tilkhoja Tilkhoja 01 Tilkhoja 22

Janakichak Gourangachak 01 Paramanandapur 59

Charandaschak Gourangachak 03 Paramanandapur 160

Mathurichak Tilkhoja 04 Paramanandapur 240

Training Compendium

8

Table 4. Potential seasonally flooded water bodies under South Western Zone

Name of field Mouza No. of water

bodies

Gram

Panchayat

Area

(Ha)

Ramchak Ramchak 03 Ramchak 160

Raichak Raichak 02 Ramchak 200

Sridharpur Raichak 03 Ramchak 120

Daxmin

Changrachak

D. Changrachak 08 Ramchak 416

Magra Raichak 03 Ramchak 129

Donachak Donachak 03 Ramchak 120

Mathurapur Sudampur 02 Ramchak 60

Sudampur Sudampur 03 Ramchak 120

Bakcha Bakcha 02 Bakcha 42

Madhavchak Bakcha 01 Bakcha 36

Uttyampur Uttayampur 01 Srikantha 25

Khejurtala Tilkhoja 01 Srikantha 30

Total 1458 Ha

Table 5. Potential seasonally flooded water bodies under South Eastern Zone

Name of field Mouza No. of

water bodies

Gram

Panchayat

Area

(Ha)

Buitalchak Ismalichak 02 Gojeina 200

Kalagechhia Kalagechhia 05 Gojeina 190

Masamchak Gojeina 02 Gojeina 80

Kripanandapur Kiarana 02 Gojeina 131

Kiarana Kiarana 04 Gojeina 152

Gojeina Gijina 03 Gojeina 120

Deuli Deuli 01 Naichanpur-I 26

Ballavpur Deuli 01 Naichanpur-I 23

Chiranjibpur Deuli 01 Naichanpur-I 24

Naichanpur Naichanpur 03 Naichanpur-II 120

Harduachak Gourangachak 03 Paramanandapur 80

Gourangachak Gourangachak 05 Paramanandapur 200

Uttar Changrachak Uttar Changrachak 04 Paramanandapur 100

Haridaspur Uttar Changrachak 03 Paramanandapur 60

Paramanandapur Paramanandapur 02 Paramanandapur 80

Janaberia Tilkhoja 01 Gokulnagar 26

Kumorchak Bara Kumorchak 01 Gokulnagar 29

Rasikpur Radhaballavchak 01 Gokulnagar 40

Knachichak Radhaballavchak 01 Gokulnagar 40

Total 1493 Ha

Training Compendium

9

Daxmin Anukha D. Anukha 08 Moyna-I 240

Haruli

Bhandarchak

Haruli

Bhandarchak

05 Moyna-I 280

Gopalchak Gopalchak 03 Moyna-I 200

Anandapur Anandapur 03 Moyna-I 146

Purba Daxmin

Moyna

P. D. Moyna 04 Moyna-II 160

D. Moyna P. D. Moyna 01 Moyna-II 29

Tong-Tala P. D. Moyna 02 Moyna-II 52

Shyamganj P. D. Moyna 01 Moyna-II 22

Total 2195 Ha

Sediments characteristics of some seasonally flooded water bodies of Moyna

The sediment characteristics of the soils of Moyna (Table 9) indicates that soil

texture of the impoundments were water retentive and conducive for rice cultivation. The

pH ranged between 6.02 and 6.29. The Nitrogen, Phosphorus, Organic carbon values depict

productive range for better rice as well as fish production.

Table 9. Sediment characteristics of the soils of Moyna.

Centres PH Total

Nitroge

n (%)

Availabl

e

Nitrogen

mg/100g

Available

P2O5

mg/100g

Organic

Carbon

(%)

Free

CaCo3

(%)

C/N

ratio

Sand

(%)

Silt

(%)

Cla

y

(%)

Dakshin

Changra

Chak,

6.13 0.08 45.92 0.48 1.0 5.25 12.5 48.5 28.0 23.5

Baital

Chak,

6.24 0.21 45.08 1.04 2.25 4.25 10.7 50.1 27.9 23.9

Janaki

Chak,

6.02 0.15 38.08 0.88 1.5 6.0 10.0 51.5 26.5 22.0

Gopal

Chak,

6.15 0.23 43.28 0.93 2.5 4.75 10.8 47.0 28.8 24.2

Mathuri

Chak,

6.29 0.09 45.12 0.59 1.2 5.31 13.3 52.0 24.0 24.0

Charand

as Chak,

6.21 0.18 40.21 1.13 1.8 5.92 10.0 50.3 26.7 23.0

Physico-chemical parameters of the water of some seasonally flooded water bodies of

Moyna

Training Compendium

10

The physico-chemical parameters of the water of the impoundments (Table 10) reveal that

water level supported a conductive carrying capacity resulting in better fish growth. The pH

of the waters ranged from 6.1 to 7.7 observed to be optimum. The DO level ranging from

5.8-7.9 at 1000 hrs was ideal for fish growth. The specific conductivity ranged in all

waterbodies was observed to be optimum for better fish production.

Table 10: Physico-chemical parameters of the water

Place Water

Depth

(m)

Water

Temperature

(°C)

pH DO

(mg/l)

Sp.

Conductivity

(micro

mohs/cm)

Light

intensity

(lux)

Gopalchak 1.2-1.6 27.9-32.7 6.4-

7.2

6.5-7.3 198.4-287.1 3.5-5.8

X104

Mathurichak 1.0-1.5 28.1-31.2 6.1-

7.1

6.4-7.4 199.9-278.9 5.1-6.7

X104

Charandasch

ak

1.2-1.6 27.5-31.0 6.4-

7.2

5.8-7.2 195.6-298.3 4.2-6.6

X104

Dakshin

Changra

Chak

1.0-1.5 26.1-32.3 7.3-

7.9

7.4-7.9 188.5-340.6 3.3-6.6

X104

Baital Chak 1.0-1.9 26.8-31.2 7.3-

7.7

6.0-7.8 178.4-314.2 3.6-

6.3X104

Janaki Chak 1.0-1.8 27.5-32.2 5.9-

7.0

5.9-7.2 171.4-298.5 3.2-5.3

X104

Associated flora and fauna in rice – fish farming system.

The rice- fish farming ecosystem during wet season was observed to be the hot spot

of fish food organisms ( Bhaumik et. al, 2005 ). The ecosystems rich in plankton,

periphyton, benthos support good fish production in the experimentations. The

autochthonus source of nutrients as well as allochthonus source of nutrients coming

through floodwater catalyses the luxurious growth of such fish food organisms in the

ecosystems. Again, the submerged part of rice plants acts as substratum for good growth of

periphyton. After harvesting of rice above the water level of the ecosystems, the submerged

part of the rice plants remains undistributed catalyzing periphyton growth. During this

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period the fishes get conducive environment for movement and feed on enough natural fish

food organisms, which accelerate the growth of fishes tremendously. Thus, fishes attain

maximum growth during this period vis-à-vis higher fish production. Plankters availability

in order of abundance are : Phytoplankton as Chlorophyta (Spirogyra spp., Oedogonium

spp., Dreparnaldiapsis indica, Stegeoclonium sp., Zygnema sp., Characium spp.,

Selenastrum spp., Botrycocous sp., Scendesmus spp., Sorastrum sp., Pediastrum spp.,

Eudorina sp., Volvox sp., Microspora sp., Protococcus sp., Ankistrodesmus sp.),

Cyanophyta (Anabaena spp., Gleotrichia spp., Oscillatoria spp., Spirulina sp., Tetrapedia

sp., Polycystis sp.), Desmids (Docidium spp., Cosmarium spp., Euastrum spp., Closterium

spp., Staurastrum sp., Penium spp., Desmidium sp., Pleurotaenium sp.,), Bacillarophyta

(Navicula spp., Synedra spp., Cymbella spp., Pinnularia spp., Nitszchia spp., Amphora sp.,

Diatoma spp., Melosira spp., Gyrosigma spp., Eunotia spp., Cocconeis spp., Frustulia sp.),

Zooplankton as Protozoans (Arcella spp., Centropyxis spp., Difflugia spp., Paramoecium

sp., Loxodes sp.,), Rotifera (Brachionus spp., Euchlanis spp., Testidinelia spp.,), whereas

macro zoobenthos as Oligochaets (Branchiura sowerbyi), Ostrocods (Bosmina spp.,

Eurycerus sp., Macrothrix sp., Ceriodaphnia sp., Chydorus sp., Diaphanosoma sp.,

Leydigia sp., Cyclops spp., Diaptomus spp.), Crabs (Paratelphusa spinigera, P.

hydrodromus), Ephimeroptera (Caenis sp., Cloeon sp.), Diptera (Culex sp.), Odonata

(Urothemis signata, Anax sp., Enallagma sp., Agria sp.), Masogastroda, (Pila globosa,

Digonisostoma cerameopoma, Bellamya bengalensis, Gabbia orcula), Basommatophora

(Indoplanorbis exustus, Gyralus convexiusculus, Lymnaea acuminata).

Selection of fish species

The fish species selected for rice-fish farming in the Moyna area are Catla (Catla

catla), Rohu (Labeo rohita), Mrigal (Cirrhinus mrigala), Bata (Labeo bata), Punti (Puntius

javanicus), Cyprinus (Cyprinus carpio), Silver carp (Hypophthalmichthys molitrix), Tilapia

(Oreochronius mosambica), Fresh water prawn, Galda (Macrobrachium rosenbergii), etc..

Mainly carp fingerlings are stocked when the fields are submerged with monsoon rain or

flood water taken through canal from the nearby river. The Kangsabati or Kansai, flows

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through the adjacent the area of paddy plots. The farmers are not always dependent on rain,

as the river used to bring plenty of fresh water from upper stretches. The carp fingerlings

are reared in adjacent ponds, deeper pools digged inside the chaks and finally released in

the rice plots when the paddy is sufficiently grown, so that the fishes cannot damage the

tender leaves of the plants. Carp fingerlings (10-15cm) are stocked in the plots

commensuration with rice cultivation.

During the month July-August, depending on inundation in the floodplains by rain or

river water fish fingerlings are stocked. No regular supplementary feeding are practised by

the farmers. Chopped gastropod meats are also provided as food for prawn & carnivorous

fishes. Lates calcarifer fingerlings are released to control wild fish (soft bodied fish like

gobids, chela, minnows, small prawns), which breed freely in the paddy environment and

become a good competitor of carp for food and space. Lates calcarifer can grow upto 1.5-

2.0 kg in 6 months, if they consume foods in plenty. Regular guarding, netting, sampling

etc. activities are carried out to achieve better yield by the managers.

Pesticide applications are generally avoided in this system. But in some cases yellow

stem borer or brown plant hopper have been encountered when biological control methods

are followed. Average growth of fish recorded varied between 500 and 750 gms (Table 6).

Total production, by and large, from such systems ranged from 3 to 5 t/ha.

Table 6 : Average fish growth under rice-fish farming in Moyna

Sl. No. Fish Species Av. wt. at release Av. wt. after harvest

1. Catla (Catla catla) 50-100 grms. 500-950 grms.

2. Rohu (Labeo rohita) 40-80 grms. 400-600 grms.

3. Mrigale (Cirrhinus mrigala) 35-70 grms. 300-500 grms.

4. Bata (Labeo bata) 10-25 grms. 50-75 grms

5. Punti (Puntius javanicus) 10-18 grms. 75-100 grms.

6. Cyprinus (Cyprinus carpio) 75-100 grms. 800-1000 grms.

7. Silver carp (Hypophthalmichthys

molitrix)

75-100 grms. 1000-1500 grms.

8. Tilapia (Oreochronius mosambica) 4-10 grms. 50-75 grms.

9. Galda (Macrobrachium rosenbergii) 3-5 grms. 30-80 grms.

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Paddy cultivation:

With the onset of Nor‟wester in the area during the end of February to middle of

March, tilling of land by power tiller are initiated. Immediately after the softening the soil,

if the rice fields are ready for sowing, paddy seed are broadcast @ 150kg/ha followed by

leveling. After one month deweeding and thinning are done and fertilizer-NPK is applied

@ 30-70 kg/ ha. Again after one month Urea or NPK with similar dose is applied in the rice

field.

The deep water rice (DWR) farmers used to capture naturally occurring wild fishes

and prawns in and around the field during season and at the end of the season when water

recedes. The farmers use various types of local traps, cast nets, hooks & lines etc to exploit

such fishes. In some fields, the farmers dig small ponds inside the field and harvest fishes

from those water bodies after the deepwater season was over. The common wild variety of

fishes harvested are Channa striatus, C. marulius, C. punctatus, Anabus testudineus,

Clarias magur, Heteropneustes fossilis, Notopterus notopterus, Amblypharyngodon mola,

Ambassis nama, A. ranga, Colisa faciatus, Nandus nandus, Rasbora daniconius,

Mastacembelus armatus, M. puncalus, Puntius ticto, P. sophore, Mystus vittatus etc.

Previously rice production during wet season was reported to be between 2.0 and 2.5

tonnes/ ha. where wild fish production ranged from 200 to 250 kg/ha.

The selection of rice variety Jaya cross was very significant since it can grow

normally with the rise of water level up to 5-6 ft ( 1-1.9 m) height. Even in 1 metre water

depth this variety is comfortable and can yield 4-5 t/ ha. But the Kalisankar variety (finer

than Jaya cross) can move up higher water depth more than 4 ft (1-1.2m). As this variety

(Jaya cross) was disease resistant, no pesticide was required to be applied. After 120, days

the paddy became ready for harvest. Its suitability further adhere to its compatibility with

fish culture. At the time of harvesting (120-130 day period) the farmers coluld harvest the

rice in boat/raft cutting the rice part only from the top with 0.3-0.5 m. length above the

water level (Figure 1). The harvested paddy was then taken to the farmyard and stacked in

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the center place and covered with polythene sheet to save them from rain. Finally after

drying, it was threshed and stored safely. The hay part was also used as manure or used in

the kitchen woven. The left over stumps the field get automatically decomposed in the field

and finally enriching the water body as organic manure. But after harvesting of rice, these

stumps act to catalyze rich quantity of periphyton and benthos, plankton, which accelerates

growth of fishes.

Figure 1. Rice- fish crop calendar at freshwater site.

Type

Month

Boro Crop Kharif Crop Fish

Jan Feb Marc

h

Apri

l May June July August Sept Oct Nov Dec

Rice

Fish

Cultur

e

Conclusions from Conducted Trials

In the experimentations conducted in seasonally flooded water bodies in some areas

of West Bengal under CIFRI – World Fish Centre Project, communities were encouraged

to determine the management criteria and institutional arrangements which they considered

suitable to their local conditions and social environment.

Institutional Arrangements

Arrangements between stakeholders are necessary within the context that during the

flooded season when individual plots are not discernable, the water body becomes a

temporary a common property, in contrast to the dry season in when individual land

holdings are clearly discernable and respected; this approach is needed to exploit the

resource.

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A group approach was used comprising landowners, fishers of the community and

landless laborers (with customary access rights for fishing in the flood season).

It was found that existing social harmony among the groups before the introduction of the

community-based fish culture approach was a requirement for its successful

implementation.

Selection of Concurrent vs. Alternating System

Depending on flooding pattern in the area, and on preferences among the groups.

Fish species, stocking Densities, Sizes

Recommendations were given on stocking of several fish species in a polyculture,

preferably of larger sizes to avoid predation and to achieve greater sizes at harvest.

However, the actually stocked numbers of individual fingerlings and species proportions

depended on the local availability from hatcheries and other sources.

Effects on Biodiversity (Wild Fish)

It was generally concluded that wild fish biodiversity and abundance was not

affected by the culture operation, although no specific analyses were conducted as part of

these early trials. The conclusion is based on comparisons of wild fish catch both in terms

of biomass and species composition, which was essentially similar, except for predators

such as snake head (Channa sp.) and catfish (Clarias sp.), which were reduced.

Beneficiaries and Impact

Inland capture fisheries are the most threatened globally, with a constant negative

trend. These fish are of highest importance which is reflected in constant price increases.

Fish also have a high value for nutrition of the poor due to their nutrient density and quality

(protein, oils, micronutrients) that is in highly bio-available form in most small fish species.

Need for Further Research

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There are many options for enhancing food production from fish in managed aquatic

systems. The most appropriate technology will vary from site to site. Additionally, the

social and economic conditions under which these technologies can be implemented need

to be understood. Although our recent studies in West Bengal demonstrated the feasibility

of the community-based fish culture systems, much more work is needed to understand the

social and economic viability of these approaches under different socio-cultural and

institutional environments, and to design appropriate institutional arrangements for

different social settings. Similarly, the governance arrangements for fish culture in

irrigation systems (canals, fields) also require detailed analyses if the full social value of

these resources is to be harnessed.

At the ecosystem or basin level, water provides a wide range of goods and services,

all of which need to be considered in broader analyses of the value obtained from water.

Most of the previous studies of water productivity have concentrated on measuring the

value of crop production only and excluded the existing and potential contributions by

living aquatic resources. There is, therefore, a need not only to increase water productivity,

but also to improve the methodologies for measuring water productivity.

References

Ali, A.B. 1990. Rice/fish farming in Malaysia: a resource optimisation. AMBIO 19(8):

404-408.

Anon,2002. Final report on Increasing and sustaining the productivity of fish and rice in the

flood prone ecosystems in South and Southeast Asia. World Fish Centre,

Penang;Malaysia.

Anon,2009. Hand book on fishing statistics of West Bengal. Department of Fisheries,

Government of West Bengal; 104p.

Anon, 2001 Census report 2001, Government of India.

Bhaumik, Utpal, Arthur, Robert,Pandit, P.K and Saha Suman, 2005., Community-based

Management Rice-Fish farming with adaptive Learning Approach, Workshop on

CIFRI and World Fish Center Collaborative Project, held at CIFRI Barrackpore on

August 27, 2005. 110p.

Datta, S.K., konar,S.K., De.D., Banerjee, S.K. and Pandit, P.K.,1985. Deep water rice-fish

culture, IRRi News letter,10(2):30-31.

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Mohanty, R.K., A. Mishra, H.N. Verma and P.S. Brahmanand 2002. Rainwater

conservation and rice-fish integration for enhancing land and water productivity.

Research Bulletin No. 11, Water Technology Centre for Eastern Region (ICAR),

Bhubaneswar, Orissa, India.

Nguyen, S.H., Bui, A.T., Le, L.T., Nguyen, T.T.T. and De Silva, S.S. 2001 The culture-

based fisheries in small, farmer-managed reservoirs in two Provinces of northern

Vietnam: an evaluation based on three production cycles. Aquaculture Research

32: 975-990.

Rao, A.P. and Singh, R. 1998. Rice-fish farming system. In: S.H. Ahmed (ed.) Advances in

fisheries and fish production. Hindustan Publishing Corporation, New Delhi, India,

309p.

Saha, N. K. and Bardhan Roy,S. K. 2001. Rice-Fish cultivation in seasonally flooded deep

water ecosystem in West Bengal, India. Workshop on Sustaining and increasing

the productivity of fish and rice in seasonally flooded ecosystem in South and

South East Asia. Dhaka: June 12-13.

Shyam, R. 1998. Status of fisheries in India. In: S.H. Ahmed (ed.) Advances in fisheries

and fish production. Hindustan Publishing Corporation, New Delhi, India, 309p.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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STATUS OF ORNAMENTAL FISHERIES IN WEST BENGAL, INDIA

B.K. Mahapatra, Principal Scientist

Central Institute of Fisheries Education, Deemed University (ICAR),

Kolkata Centre, Sector-V, Salt Lake City, Kolkata – 700 091.

E-mail: bkmahapatra2007@yahoo.co.in

1. Introduction

The varied forms and fascinating beauty of some fishes have attracted the people

from time immemorial and are named as „ornamental fish‟. In China and Japan, gold fish

and koi carp have been used as an ornamental fish since long. Aquarium keeping of fish

began in 1805 and the „first public aquarium‟ was opened at Regent‟s Park in England in

1853. Thereafter, aquaria keeping picked up further and by 1928 there were 45 display

aquaria opened, with over 500 of public aquaria presently functioning worldwide.

However, the global market of ornamental fish for public aquaria is less than 1% at present

and over 99% of the market continues to be confined to hobbyists. The ornamental fish

keeping, which started as a hobby has now turned out to be a commercial aqua-business

and has taken the shape of an industry. The value of the entire industry has been estimated

at US $ 15,000 million. Considering the enormous and diverse indigenous fish resources of

the country in general there is immense scope for her to become a potential candidate and a

strong competitor in the international ornamental fish trade.

1.1.1. Common freshwater ornamental fish

In India, 288 species of exotic ornamental fishes exist of which 261 species are egg

laying and 27 species are live bearing. Besides, there are a large number of common food

fishes in India having a steady demand as ornamental fish due to their attractiveness. These

fish species are popularly known as „Indian Aquarium Fish‟ by the ornamental fish traders

and hobbyists. In West Bengal, the diversified fish fauna offers a wide group of small

fishes which are unwanted for conventional farming, but having a good potential in global

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fish market. Study of such fishes in the wild state indicated presence of diversified group

having export value. Altogether a total of 176 indigenous ornamental fish species have

been recorded from the diverse fresh water bodies of North and South Bengal which

belongs to 98 genera under 41 families and 10 orders. Majority of the fish species

belonged to Cypriniformes (76) followed by Siluriformes (51), Perciformes (30),

Clupeiformes (05), Cyprinoodontiformes (04), Anguilliformes (03) Osteoglossiformes (02),

Synbrachiformes (02), Gasterosteiformes (01) and Tetraodontiformes (01). Further, the

family cyprinidae contributed maximum number of species (56), followed by Sisoridae

(17), Balitoridae (13), Bagridae (12), Schibeilidae (08), Channidae (06),

Clupeidae/Belontidae/Mastacembelidae/Siluridae (04) Gobidae/Mugilidae (03),

Ambassidae/Aplocheidae/Ariidae/Nandidae/ Notopteridae/ Olyridae/Psilorhyndae and

Synbracidae (02), Amblycipitidae/Anabantidae/ Angilidae/Belonidae/Centrpomidae/

Chacidae/ Claridae/Eleotridae/Engraulidae/ Heteropneustidae/Hemiramphidae/Lobotidae

Moringuidae/ Ophichthidae/ Pangasidae/ Plotocidae /Scatophagidae/ Sygnathidae/

Tetraponidae and Tetraodontidae (01).

Diversity of Indigenous Ornamental fish in West Bengal

The West Bengal are blessed with many ornamental fish species like loach, barbs,

danio, snakeheads, trout, rasbora, gouramy, catfish, clown fish, algae eater and goby. These

include both classified and non-classified type of aquarium fish. The small fishes like Botia

dario, Danio dangila, Puntius shalynius and Schistura reticulofasciatus are classified type

of ornamental fish, which can be reared in aquarium through out their life span. On the

other hand, some larger food fishes like Neolissocheilus hexagonolepis, Labeo gonius,

Channa marulius, Bagarius bagarius and Rita rita are also now treated as ornamental fish

in their juvenile stage and termed as non-classified ornamental fish. The native ornamental

fishes can be classified based on their diversified character such as, beautiful colour (e.g.,

Pseudecheneis sulcatus, Tetradon cutcutia), stripes & banding pattern (e.g., Botia rostrata,

Brachydanio rerio), Chamelionic habit (e.g., Badis badis, Puntius shalynius), jumping

behaviour (e.g., Esomus danricus, Chela laubuca), charming predatory habit (e.g.,Channa

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orientalis, Glossogobius giuris), calm behaviour (e.g., Ctenops nobilis, Nandus nandus),

transparent body (e.g., Chanda mama, Pseudambassis ranga), small size (e.g.,Danio

dangila, Brachydanio rerio), hardiness (Anabas testudineus) and suckers (e.g.,Garra gotyla

gotyla, Garra mcllendi). Besides, some larger food fishes like Neolissocheilus

hexagonolepis, Labeo gonius, Channa maurulius and Rita rita are also now treated as

ornamental fish in their juvenile stage and are termed as non-classified ornamental fish.

Breeding of Ornamental fish

Different groups of fishes reproduce in different ways. An understanding of how the

various species go about breeding is indispensable to undertake breeding programme. In

general the fishes can be divided into two broad categories – Egg layers and Livebearers.

Within this basic grouping, different species have their own ways of ensuring the survival

of at least a proportion of their offspring.

(i) Livebearers

Livebearers are fish that bear live young ones. There are two types of livebearers:

ovoviviparous, where the eggs form and hatch within the female before birth; and

viviparous, where no eggs are formed, and the young are nourished through an umbilical-

like cord or from secretions by the female. Livebearers are often prolific, easily bred

species.

Spawning tank

The live bearing fishes are the easiest of all aquarium fishes to breed; indeed, the

only problem usually encountered is that of saving the young from the cannibalism of their

parents. Various traps have been designed for the relatively rapid separation of the young

from their mother at birth. The most satisfactory arrangement is a screen of mosquito

netting on a stainless steel or wooden frame, which can be wedged across the tank so as to

confine the female to one end while allowing the young to pass. Despite of all these

devices, the more natural method is having plants in abundance to provide shelter for the

young, and removing the mother at the earliest chance. The best plants for young

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livebearers are masses of Myriophyllum, Ambulia, Nitella, Utricularia, etc.

Guppy Black molly

Sword tail Platy

Fig-1: Live bearer ornamental fishes

Fig-2: Breeding of live bearer ornamental fishes

Raising the fry of Livebearers

Livebearer young are quite large, and young fishes can feed on dry or other prepared

food straight away. If they are given only prepared food, growth will be poor, but a mixture

of live and dry food is quite satisfactory. In the early stage, feeding of live food is very

important for good development. Later it matters much less, although the fishes will still do

better with a good proportion of live food. Suitable first live foods are micro worms, newly

hatched brine shrimp, shredded earthworms, daphnia, newly hatched mosquito wrigglers or

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shredded white worms. Suitable dry foods include any fine powder food, such as dried

shrimp finely ground, fine cereals, and liver or egg powder.

(ii). Egg layers

Most aquarium species are egg layers with external fertilization. Within this group,

fishes can be divided into five groups - egg-scatterers, egg-depositors, egg-buriers, mouth-

brooders, and nest-builders; depending on how they lay and handle their eggs.

Egg-scatterers

These species simply scatter their adhesive or non-adhesive eggs to fall to the

substrate, into plants, or float to the surface. The egg-scatterers either spawn in pairs or in

groups. There is no parental care given and even they eat their own eggs, so large amounts

of eggs are produced. The Characins and Cyprinids lay their eggs this way.

Spawning tank

Because egg scatterers often eat their own eggs, the spawning tank has to be set-up

so that the eggs fall out of the reach of parents. For egg scatterers like Barbs and Danios,

which lay non-adhesive eggs, the spawning tank can be furnished with a substrate

consisting of two layers of marbles or nylon netting just above the tank floor. As the eggs

are laid, they fall through the marbles or the netting out of the reach of the parents. After

spawning is over, the eggs or the parents can be removed.

For egg scatterers that lay adhesive eggs like Tetras, the spawning tank should be furnished

with a substrate. The tank should be planted with fine-leafed plants. The eggs are laid

amongst plants, and adhere to the fine-leaves. The parents should be removed after

spawning.

Egg-depositors:

In this case, the eggs are either laid on a substrate, like a stone or plant leaf or even

individually placed among fine leafed plants like Java moss. Egg- depositors usually lay

less egg than egg-scatterers. Egg-depositors fall into two groups: those that care for their

eggs, and those that don‟t care. Among egg depositors that care for their eggs are cichlids

and some catfish. Cyprinids, various catfish, and Killifish make up the majority of egg-

depositors that do not care for their young ones. These species lays their eggs against a

surface, where the eggs are abandoned. These species do not usually eat their eggs.

Spawning tank

For those egg-depositors that care for their young ones, the parents can remain in the

tank after spawning. Substrate spawners, depending on the species, should be given a tank

furnished glass panes, broad-leafed plants, or flat stones for spawning sites. Some species

such as Discus and Angelfish prefer vertical surfaces. For cavity spawners, flowerpots

turned on their side, coconut shells, and rocky caves are suitable spawning sites. The tank

should be furnished with either live or plastic plants to give the fish a sense of security.

Egg-depositors that do not care for their young ones should be given a tank

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furnished with fine and broad-leafed plants, Java Moss, or artificial spawning mops. After

spawning the parents or plants with the eggs should be removed. If the plants containing

eggs are removed, new plants should be placed in the tank for future spawning.

Egg-buriers:

Fishes in this group usually inhabit waters that dry up at some time of the year. The

majority of egg buriers are annual Killifish, which lay their eggs in mud. The parents

mature very quickly and lay their eggs before dying when the water dries up. The eggs

remain in a dormant stage until rains stimulate hatching.

Spawning tank

A peat-moss substrate is one of the best substrates for egg-burying species. The peat

moss can be removed after spawning and placed in a plastic bag to be stored for weeks to

months (depending on the species). A new peat-moss substrate can be placed in the tank

for further spawning. In order to initiate hatching, the stored peat can be immersed in soft

water.

Mouth-brooders:

Mouth-brooders carry their eggs or larvae in their mouth. Mouth brooders can be

broken up into ovophiles and larvophiles. Ovophiles or egg-loving mouth-brooders lay

their eggs in a pit, which are sucked up into the mouth of the female. The small numbers

of large eggs hatch in the mother‟s mouth, and the fry remain there for a period of time.

Many cichlids and some labyrinth fish are ovophile mouth-brooders. Larvophile or larvae-

loving mouth-brooders lay their eggs on a substrate and guard them until the eggs hatch.

After hatching, the female picks up the fry and keeps them in her mouth. When the fry can

feed for themselves, they are released.

Spawning tank

Ovophile mouth-brooders can be bred in the main aquarium because the eggs are

protected in the mouth cavity. However, it is better to separate mouth-brooders with eggs

because of their potentially aggressive behavior. There are no special breeding tank

requirements other than the usual tank set-up for the species. Larvophile mouth-brooders

should be placed in a separate breeding tank because the eggs are not protected in the

mouth, but laid on a surface where they are open to predators.

Nest-builders:

Many fish species build some sort of nest for their eggs. The nest ranges form a

simple pit dug into the gravel or the elaborate bubble nest formed with saliva-coated

bubbles. The Gouramis, Anabantids and some catfish are the most common of this type of

spawners. Nest builders practice brood care.

Spawning tank

Nest-builders should be provided with material with which to build their nests. For

bubble-nest builders, fine leafed and floating plants should be provided, and the tank should

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have no water current to disturb the nest. Species that build nests in the substrate should be

given fine gravel or sand.

Raising the fry of Egg layers

When the eggs hatch, the larvae that emerge look nothing like the parent fish.

Instead, the larvae have a large, yellow yolk sac and are barely able to swim. The larva

feeds on the egg sac until all the yolk is absorbed. Once the yolk sac is absorbed, the fry

starts feeding on external food. The fry of small fish can be first fed with Infusoria, “green

water,” or egg yolk. Later these fry can be fed larger foods like white worms, Daphnia,

Artemia nauplii, and ground flakes. These foods are good as a first food for slightly larger

fry such as those of cichlids. Once the fish grow larger, larger foods like brine shrimp,

larger Daphnia, flakes, insect larvae, and chopped Tubifex worms are accepted. The fry

should be fed several times a day. Many species need periodic sorting by size, so that larger

fish do not cannibalize smaller fish.

Breeding and Culture of Gold Fish (Carassius auratus)

Common gold fish, Carassius auratus, belongs to the order: Cypriniformes and

family Cyprinidae. It is an omnivorous fish and feeds on a wide variety of live feed and

accepts artificial feeds also. Colour of gold fish ranged from Red, Orange, Silver, Black,

Brown, White and many more. More than 30 varieties of gold fish are available. The most

common varieties are Oranda, Lion head, Fan tail, Telescope eye, Bubbles eye, Albino,

Pearl scale and several others.

Fig-3: Gold fish

Required water parameters such as pH 7.0 to 8.0, temp 25 to 30 oC, dissolved oxygen 5 to 7

ppm, dissolved free carbon dioxide 0 to 4 ppm and total alkalinity 80 to 100 ppm. Electric

aerator (pump) raise dissolved oxygen level of water to 6-7 ppm which is necessary for

breeding. Partial water exchange (25 to 30 %) is very much essential from breeding tank.

Breeding carried out in “Gamlas”, 40 to 60 l capacity which is made up of clay or cement

or in rectangular glass aquarium of 50 l capacity. General fecundity of gold fish ranged

from 500 – 700 depending upon the size. Sex ratio is kept 2:1 (male:female) to ensure

successful breeding. Eggs are generally released during night hours. Fertilized eggs are

transparent and grayish in colour and unfertilized eggs are transparent white. Eggs are

sticky in nature; substratum may be maintained with soft weeds, tiles, corrals etc., for

settlement of eggs.

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Fertilized eggs hatch in 4 to 7 days depending upon water temperature. No parental care is

seen. Parents eat hatchlings. As a result parents will be removed after breeding.

Sex Determination:

In case of male gold fish white bumps or tubercles develop on the operculum and

pectoral fin. Main ray of pectoral fin have thick edge in case of male but thinner edge in

case of female. Fins become more pointed in case of male but look rounded in female. Vent

assumes a concave shape with a small opening in male and vent becomes convex and large

opening in case of female. Abdomen is seen to be smaller in male but large in case of

female.

Brooders

Base for adhesive eggs Eggs on mop (inside water) Eggs on mop

Newly hatched ones Gold fish fry in rearing tank Gold fish ready for market

Fig-4: Different stages in gold fish breeding

Culture of common gold fish:

The culture of common gold fish is being taken up normally in cement tanks of

dimension 10‟ x 5‟ x 2‟ or 12‟ x 6‟ x 2‟. Preferable temperature for culture is 15.5 to 24 oC.

pH range 7.0 - 8.0 and prefer moderate hardness of 50 – 75 mg CaCO3 per litre and oxygen

level of 5 to 7 ppm. Generally 300 fry (23 mm) of gold fish are stocked in each cement tank

of dimension 10‟ X 5‟ X 2‟.

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26

The newly hatched young ones depend upon their yolk size as a food source for a couple of

days. When the fry become free swimming they are being fed with Artemia, Daphnia,

Moina, Tubifex worm and other planktons. Young ones of 2 – 3 days old feed with egg

yolk and dried milk powder. After 10 days the young ones start feeding the tubifex worms

and maintained till their disposal.

Breeding of Tiger Barb (Barbus tetrazona)

Out of more than 30 commercially important species of freshwater ornamental fishes

reported from Indian waters tiger barb, Barbus tetrazona is one of them. This species is

hardier and active and does not require much of attention in regard to its basic needs. Their

large scales, bright colors, schooling behavior and ease of maintenance and of breeding

them have made the fish popular in the aquarium trade. Though there are 1078 barb species

reported from all over the world, only 70 barb species are commercially important because

of their color pattern.

Fig-5: Tiger barb

Maturity of tiger barb:

The tiger barb which is four banded usually attains sexual maturity at a total body

length of 20-30 millimeters (2-3 cm) (or) at approximately 6-7 weeks of age. Although

tiger barbs are not sexually dimorphic, males display a bright red coloration on fin rays and

snout while females tend to be more round in the abdominal region and slightly less

colorful. Females are usually larger than males. They can obtain a maximum length of 7 cm

and body depth at 2 cm. All related barbs mate in a ratio of one male to one female with the

male displaying aggressive behavior while the female is submissive.

Brood stock conditioning:

Conditioning the sexes in separate tanks is an important step in the seed production

process. Tiger barbs for use as brood stock (2 to 3 cm body length) are first collected from

a production ponds or natural water bodies and graded with size graders. Sexually mature

females are identified by full round abdominal region and sexually matured males are

identified by bright red colors on the fin rays. The selected brooders are then placed sex-

wise in separate circular or square or rectangular conditioning tanks. Rectangular tanks are

more conductive for removing and selecting brooders. A stocking density of one fish per

four liters of water is recommended. The conditioning tank should be provided with

sufficient aeration and water exchange at a rate of 20% per day. The separated fish are

Training Compendium

27

conditioned by a diet of frozen blood or tubifex worms of Artemia. High quality flakes or a

prepared taste are given as feed at least twice or thrice per day for a period of two weeks.

Since wild tubifex causes infection to broodstock utmost care should be exercised to

prevent this, through needed cleaning etc. During conditioning good water quality should

be maintained as the conditioning of diets can lead to fouling of the water. Lack of proper

conditioning will result in greatly reduced number of successful synchronized spawning.

Spawning of Tiger Barb:

Submerged aquatic plants or roots are often chosen by the females as the substrate

on which they deposit eggs. During actual spawning event, the male clasps the female with

its fins during which eggs and sperms are released over the substrate. The behavior may

last for several hours or until all the eggs are released. An average of 300 eggs can be

expected from each female per spawn. Tiger Barb will consume the eggs greedily after

spawning. Therefore parents must be removed as soon as possible (Vogt and Wermuth,

1961; O‟Cornel, 1977 and David, 1983). Spawned eggs are adhesive, negatively buoyant in

freshwater and on an average 1.18±0.05 mm in diameter. The eggs will hatch in 3 days if a

temperature of 25º to 27º is obtained.

Fig-6: Male and Female Tiger barb Fig-7: Young ones of tiger barb

Breeding of Angel Fish (Petrophyllum Scalare)

Angel fish breeding has progressed into an art with the development of the veil

finnages, superveil finnages and the many color varieties. It is remarkable that all of these

forms came from the original standard silver angel fish from the wild.

Fig-8: Angel fish

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28

Sex identification:

It is difficult to identify male and female in the angel fish but at the time of spawning

genital papillae are the reliable identification of sex determination. These look like little

nipple-like projections and are called ovipositors. The female‟s ovipositor is larger and

more blunt than the males which is slender and more pointed. These protuberences, which

appear at the vent, are used respectively for depositing eggs and fertilizing them.

Male & female angel fish Set up for mass scale breeding

Baby angel Angel ready for marketing

Fig-9: Different stages of Angel breeding

Spawning tank:

Large aquarium tank of 80 to 100 l capacity is ideal for spawning tank. Spawning

tank water requires a slightly acidic pH level of 6.6 to 6.8. The fish can spawn at higher pH

of 8 but fish tend to spawn more readily at the lower pH levels mentioned above. It is

especially important to keep the water acidic if you are going to keep the eggs with the

parents. Maintaining the pH 6.6 to 6.8 for hatching provides an optimum pH condition for

hatching eggs. The tank is furnished with slates or glass plates that are slanted at angle to

lay eggs upon. An air stone giving mild aeration may be placed at the corner.

The pair will select a spawning site and thoroughly clean it about two or three days

before actual spawning takes place. When the cleanliness of spawning site finally meets the

approval of the parent fish, the female will make a few test runs. She will pull her ventral

fins of feelers close to the lower sides of her abdomen and her anal fin will be situated so

that her entire lower line is relatively straight. Her ovipositor will then be able to make full

Training Compendium

29

contact with the slate; glass plate or whatever chosen for a spawning site. The male will

then make a few practices run too before the actual spawning takes place.

When spawning actually takes place, the female will pass over the site and eggs are

deposited which adhere to the surface. The male then moves in and scoots along over the

string of eggs just laid and fertilizes them, his fins taking the same position as the females

so he can press closely to insure a higher fertilization rate.

The male and female angel fish will take runs passes over the spawning site until

several hundred or more eggs have been laid, depending on the size and condition of the

female prior to spawning. The parents will hover closely over the spawn and fan

continuously with their pectoral fins to create a circulation of water over and around the

eggs. Some fertilized eggs will turn white in a matter of hours and will be removed by the

parents.

Hatching Eggs:

For the successful hatching of the eggs it is recommended to use very soft water

preferably rain water or distilled water because it has naturally low pH of 6.2-6.5.

When the spawning is over the glass plate should be removed from the spawning

tank and place it in a 30-50 l tank with sponge filter and a piece of slate leaned up against a

side wall. An air stone should be placed in the jar in such a way that somewhat vigorous

stream of air bubbles does not hit the eggs directly. Few drops of 10% Methylene blue was

added to prevent the fungal attack on eggs. Hatching should occur in about 36-48 hours

depending on the temperature. There will be a period after hatching and before free

swimming when the fry will stick together. At this time increase the aeration so all the fry

will have access to sufficient oxygen.

Do not put food in the tank till they fry are free swimming. After about 3-5 days

when they are free swimming, introduce newly hatched brine shrimp into the tank for the

fry to eat. Rearing tanks for baby angels that are two weeks and older incorporate normal

dechlorinated tap water. Ten liter for every hundred liter of water is changed daily from the

bottom of the tank where all the detritus accumulates. These rearing tanks are not treated to

lower acidity.

Feeding Schedule: One week to three weeks

Angel young ones do not need any type of feeding until they are in free swimming

stage. It takes about four to six days depending on the temperature. When the young fry

became free swimming feed them newly hatched brine shrimp (Artemia) or Moina.

Brine shrimp is fed directly to the young at first to make sure that no excess is

floating around in the tank for hours at a time. Three or four feedings per day should be

sufficient. Any brine shrimp floating around after 20 minutes is a sign that you are feeding

too much. Remember, feeding in light quantities decreases overfeeding and associated

problems such as ammonia and disease.

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30

Three weeks to five weeks:

After three weeks the fry attain a size in which they will accept finely crushed flake

foods. Flake foods are provided in small quantities as a supplement.

After three weeks brine shrimp can be fed and eaten within 15 minutes of adding it to the

aquarium.

Five weeks to seven weeks:

At five weeks of age, the young angel fish are introduced to dry foods. A small

amount is fed twice daily until the seventh week. During this time, the small angel fish will

attempt to eat the dry flakes but small angel fish will attempt to eat the dry flakes but they

will usually spit it out soon after taking it into their mouths. Some will eat the flakes and

some will not. Around the seventh week the angel fish begin accepting dry flakes and there

should be few flakes, if any remaining on the bottom of the tank like the previous weeks.

Six weeks to adult hood:

At about six weeks of age, the young angel fish have reached a size in which they

will begin accepting blended beef hurt cubes. Baby brine shrimp can still be given to the

young angels for upto three months but beef liver and flakes are all that is necessary for

quick growth.

Breeding of Gouramies:

Gouramies although closely related to Bettas, do not have their fighting depositors.

A under good conditions they are friendly community fish. In all gouramies, the pelvic fins

are shaped as long as thread-like feelers, which can be moved in all the directions. Popular

aquariums varieties of gouramies are the giant gourami (Colisa fasciata), dwarf gourami

(Colisa lalia), pearl gourami (Trichogaster leeri), blue or three spot gourami (Treichogaster

trichopterus), moonlight gourami (Trichogaster microcephalus), snakehead gourami

(Trichogasrter pectolaris), chocolate gourami (Sphaericthys osphronemoides) and kissing

gourami (Helostoma temmincki).For describing the breeding of gouramies, a typical

example of blue or three spot gourami is presented below.

Fig-10: Male & Female Giant Gourami, Colisa fasciatus

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31

The three spot gourami breeds during April to August. During breeding season

mature male develops dark colouration and female show buldging abdomen. While making

breeding pair care must be taken to select the mature female, which is ready to spawn. This

is because males of blue gourami are very aggressive in nature and tend to kill female, if

she is not ready to breed. Aquarium tanks of 50-80 litre capacity can be used for breeding.

The water level in the aquarium should not be more than 25 cm. One or two pieces of

floating plants and beetle leaves may be floated on the water surface to hold the bubble

nest. The tank should not be provided with aeration. The pairing of blue gourami is made in

the ratio of 1:1. If the male in breeding condition, it will start making nest within one or

two days. The bubble nests floats under the plant leaves and looks like soap foam. The

male drags the female under the leaves and during courtship female releases a batch of 20-

25 eggs. The male pick up the eggs and attach them in the floating nest.

1.1.2. Culture of ornamental fish

Ornamental fish farming is identified as an alternative income generating activity and is

also becoming popular in India. The main advantage of this trade is that besides the rural

areas, it can be practiced in urban areas too. Glass aquaria, concrete tanks and net-cages are

commonly used for the culture of ornamental fishes. Generally two types of rearing are

done. The fry of common local bred egg layers and live bearers are reared. On the other

hand, imported fry of some exotic fry of some exotic price fishes are reared by the local

farmers against some wages. An interested culturists can begin with species like gold fish

(Carassius auratus), platy (Xiphophorus maculates), sword tail (Xiphophorus helleri),

guppy (Lebistes reticulates) etc.

1.2. Feed management

Types of feed is an important constituent in ornamental fish farming and high expenditures

are generally incurred on feed. Hence, the right type of feed in appropriate quantities

would ensure a higher survival and growth and also a higher economic return. The feed

requirement of different species vary and hence a thorough knowledge of the food and

feeding habits of the culturable species is a pre-requisite.

Nowadays, different types of feed are available in the hobby shops; however, most of these

feeds are expensive. Hence, the culturists can prepare the feed using locally available

materials which would be more economical and cost-effective. Feeds are of two main types

viz. formulated dry feeds and live feeds.

1.3. Live feed

In aquarium industry, live feed is very important and the success of ornamental fish

breeding and culture depends mainly on the constant supply of live feed. The larval stages

of all aquarium fishes depend wholly on the live food and even the adults of these fishes

show a greater preference to the live feed. The carotenoid pigments, which are very

essential for enhancing the colour of ornamental fishes, can be derived from the live feed.

Thus live feed is considered as living nutritious capsule as they contain all the essential

Training Compendium

32

nutrients, which enhances the breeding efficiency and excellent growth and colouration of

fishes.

1.3.1. Types of live feed

The live feed which are used for ornamental fish breeding and culture are of many types.

Some of them are infusoria, daphnia, tubificid worms, mosquito larvae, artemia, moina etc.

1.4. i) Infusoria

The infusorians are tiny single celled protozoans which exist in almost all water bodies.

They form an excellent starter food for the newly hatched spawn after the yolk sac

absorption is complete. Among the many species of infusoria, Paramecium and

Stylonychia are the commonly cultured species for feeding the larvae. They are mostly

seen in ditches containing rotten kitchen waste having foul smell.

ii) Brachionus

Brachionus species are excellent first feed for the larval fish because of its small size, slow

swimming speed and habit of staying suspended in the water column and the ability to be

cultured at high densities.

1.4.1. iii) Tubificid worms

Tubifex are small, reddish worms upto 2cm long, and they occur in large numbers in

flowing sewage drains. When disturbed, they enter into the mud.

iv) Artemia

Artemia is a tiny saltwater crustacean brine shrimp and the nauplii of which are excellent

diet for the aquarium fishes, both for adults as well as for their young ones. The Artemia

cysts which are generally collected from the salt pans are available in markets in tins.

The Artemia cysts can be hatched in glass jars at a room temperature of 27-30oC. To half a

litre of cooled boiled water, 10-15 g of salt is added. The water is aerated and to this

Artemia cysts are added @ 0.5 to 1.0g/litre of water. The favourable pH is 7.5-8.5.

Hatching takes place in about 24 hours. After hatching, the nauplii are harvested in a

100 m mesh net by taking advantage of their phototactic nature by providing light of 1000

lux. After collecting, the nauplii are thoroughly washed and stocked in a container

containing seawater of 25-35 ppt salinity and fed to the fish larvae as per the requirement.

1.4.2. Formulated dry feeds

In addition to the live feeds, the ornamental fishes are also maintained using formulated dry

feeds. Different types of formulated feeds are available in the markets in the form of

flakes, crumbles and pellets. However, most of the feeds available in the markets are

expensive for the very fact that they are imported from other countries like Singapore,

Hong Kong, Japan, Korea and Thailand. Hence, the culturists can prepare good quality

feeds for his ornamental fishes using locally available ingredients.

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33

It has been reported that all the fishes require crude protein level in a range of 30-45%,

crude lipid 4-8% and carbohydrate 30-50%. Based on this, the feed can be prepared for the

ornamental fishes with 40-50% protein, 4-6% lipid & 40-50% carbohydrate for the young

ones and 30-35% protein, 6-8% lipid & 40-50% carbohydrate for the adult fishes. In

addition, 1% each of vitamins and minerals can be added to the feed.

For preparing the feed, the feed ingredients are selected on the basis of their availability,

nutrient composition and physical properties. The ingredients should be free from

pathogen and should be of good quality. The ingredients that are commonly used are the

vegetable sources like the groundnut oil cake, rice bran, tapioca flour, wheat bran, wheat

flour, maize bran and soybean meal and animal sources like fish meal, silkworm pupae

meal, prawn head meal and earthworm meal.

1.5. Health Care

In ornamental fish farming, proper health management is to be taken throughout the culture

period. Tap water is kept stagnant for one or two days for dechlorination, if any chlorine is

present. In case of pond water, methylene blue is used @ 3.5 mg per litre to purify the

water. Quarantine tanks are used for new fish to prevent the entry of new pathogens.

Sometimes, some chemicals like copper sulphate, potassium permanganate, malachite

green, formaldehyde and antibiotics like oxytetracycline or terramycin are used to prevent

the infection.

Marketing of ornamental fishes

Ornamental fish marketing is not well organised. Only few traders collect the native

ornamental fishes through local collectors and supply them to different exporters based in

Kolkata, Howrah, Mumbai, Chennai, Thiruvananthapuram, and Cochin for export. The

ornamental fish market of Kolkata (locally known as „Galif Street Market‟) is the largest

wholesale market of ornamental fish in the Eastern and North Eastern Zone of India.

Actually it is a weekly market of pet animals like ornamental fish, turtles, cage and poultry

birds, puppies, white rats, guinea pigs, rabbits, and mongoose. Different indoor and

decorative plants including bonsai and cacti occupy a large portion of the market area. All

needed accessories of these hobbies like seed and seedlings of different plants, planting

pots, fertilizers, fish feed and aquarium accessories, different types of cages and birdfeed

are also available here. So, though this more than hundred years old haat is a favourite

destination of the hobbyists on Sunday morning, this is also a large business place with

huge wholesale and retail turnover of not less than five lakhs rupees. Ornamental fish

contributes a large portion of it. With the rich biotic resources, favourable climatic

condition and available manpower West Bengal is now one of the pioneering states in

ornamental fish trade. Kolkata is the highest ornamental fish exporting city of India. Major

Indian export goes from Kolkata followed by Mumbai and Chennai. The trade of the

ornamental fish of ecologically diverse north eastern states also is routed through this

market. This wholesale market is the hub of the ornamental fish trade of this zone of our

Training Compendium

34

country. The positional advantage of this market has made it easier for it to become the

centre of immense importance and scope.

Nearly 200 species of ornamental fishes are exported from West Bengal. The

demand of the ornamental fish was very much fluctuating during different years and

seasons. The price in local hobby shops as well as in „Gallif Street Market‟ ornamental fish

market is also good and varies between Rs.5-100/-. The FOB price offered by the exporter

for native ornamental fish is significantly high and varies from about 0.06 US$ to 4.825

US$.

Indian export on Ornamental fish mainly depends on West Bengal. About 50% of

export, by value, of the ornamental fish takes place through Kolkata port. The exports were

made to Singapore, USA, Japan, UK, Germany, Sri Lanka, Spain and other countries. In

the global ornamental fish trade, USA tops the list of importing countries, while Singapore

occupies the top most slots among the exporting countries.

1.5.1. Economics breeding and rearing of ornamental fish

Encouraging income is possible through breeding and rearing of ornamental fish which

depends on investment, management practice, marketing facilities etc.

In breeding and rearing of gold fish, by investing a total of Rs.30, 000.00, one can earn a

monthly profit of Rs.2500/- (Table 1).

In breeding and rearing of angel fish, from 10 breeding pairs of angel, a minimum of

20,000 young ones can be produced annually and from the sale of these produce, an annual

profit of Rs.52, 200/- can be easily achieved (Table 2).

The breeding and rearing of live bearers can be initiated even with a minimum available

space and moderate investment. By investing Rs.48,000/-, which includes both the capital

cost and the culture cost, a monthly income of Rs.4,000/- can be easily realised in the first

year (Table 3).

Table1. Economics of gold fish Breeding and rearing unit

S.No Particulars Rate (Rs.) Total value (Rs.)

A. CAPITAL COST

1 Cost of shed house 5000.00 5000.00

2 6 Cement tanks (2m x 1.5m x 1m) 2000.00/tank 12000.00

3 6 Air pumps 200.00/piece 1200.00

4 Other fittings 1800.00

SUB TOTAL 20000.00

B. CULTURE COST

1 Breeders 10 pairs 400.00/pair 4000.00

2 Feed for 1 year 4000.00

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35

3 Electricity charges 1200.00

3 Others 800.00

SUB TOTAL 10000.00

C. SALE

1 Total production – 1500 per female

Breeding 4 times in a year

Total production 6000 per female

Total production from 10

females=60000 (annually)

1.00 60000.00

D PROFIT [C – (A+B)] 30000.00

Table 2. Economics of angel breeding and rearing

S.No Particulars Rate (Rs.) Total value (Rs.)

A. CAPITAL COST

1 Shed house 5000.00 5000.00

2 10 glass aquaria (122cm x 48cm x

48cm) without lid

1400.00/piece 14,000.00

3 10 glass aquaria (75cm x 30cm x 30cm) 800.00/piece 8,000.00

4 20 plastic trays (40cm x 30cm x 9cm) 200.00/piece 4,000.00

5 10 Air pumps 200.00/piece 2000.00

6 10 Water heater 500.00/piece 5000.00

Sub Total 38,000.00

B. CULTURE COST

1 Cost of 10 pairs 500.00/pair 5,000.00

2 Cost of feed for 1 year 1000.00/month 12,000.00

3 Electricity charges 400.00/month 4,800.00

4 Other cost 2,000.00

Sub Total 23,800.00

C. SALE

1 After 45 days of rearing (4000 pieces) 4.00/fish 16,000.00

2 After 60 days of rearing (4000 pieces) 5.00/fish 20,000.00

3 After 90 days of rearing (12000 pieces) 6.50/fish 78,000.00

Sub Total 1,14,000.00

D. PROFIT [C – (A+B)] Rs.52,200.00

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1.6. Table 3. Economics of breeding and rearing of live bearers

S.No Particulars Rate (Rs.) Total value (Rs.)

A. CAPITAL COST

1 Cost of shed house 5000.00 5000.00

2 4 Breeding tank (cemented) 2m x 1.5m

x 1m

Rs.2000/tank 8,000.00

3 4 Delivery tank (glass aquaria) of size

75cm x 30cm x 30cm

Rs.800/aquariu

m

3,200.00

4 4 Spawn rearing tank (glass aquaria) of

size 122cm x 48cm x 48cm without lid

Rs.1400/aquari

um

5,600.00

5 4 Fry rearing tank (cemented) 2m x

1.5m x 1m

Rs.2000/tank 8,000.00

Sub-total 29,800.00

B. RECURRING EXPNDITURE FOR

ONE YEAR

1 800 females, 200 males of guppy,

molly, sword tail & platy

Rs.5.00/fish 5000.00

2 Cost of feed for 1 year Rs.500.00/

month

6,000.00

3 Hand nets, brood cage etc. 2,800.00

4 Electricity charges Rs.200/month 2,400.00

5 Chemicals, medicines, packing

material, buckets, etc.

2,000.00

Sub-total 18,200.00

C. SALE

Gross income from the sale of 76800

nos. of fish reared for one month (@ 40

nos./female/cycle from 3 cycles/year,

and considering a survival of 80%)

Rs.1.25/pc., 96,000.00

D. PROFIT [C – (A+B)] 48,000.00

For Further Reading

Ghosh A., Mahapatra, B.K. and Datta, N.C. 2002. Studies on native ornamental fish of

West Bengal with a note on their conservation. Environment & Ecology 20 (4) :

787-793

Ghosh, A., Mahapatra, B.K. and Datta, N.C. 2003. Ornamental fish farming –

Successful small aqua business in India. Aquaculture Asia 8 (3): 14-16.

Training Compendium

37

Mahapatra, B. K., Vinod, K. and Mandal, B.K. 2003. Scope of ornamental fishery in

Meghalaya. Page 397 to 401 In: B.P. Bhatt, K.M. Bujarbaurah, Y.P. Sharma, and

Patirama (eds). Approaches for Increasing Agricultural Productivity in Hill and

Mountain Ecosystem. ICAR Research Complex for NEH Region, Umiam,

Meghalaya

Mahapatra, B. K., Vinod, K. and Mandal, B.K. 2003. Studies on native ornamental fish of

Meghalaya with a note on their cultural prospects. Aquacult 4(2) : 173 – 182.

Mahapatra B.K., Vinod, K. and Mandal, B.K. 2004. Fish biodiversity of North Eastern

India with a note on their sustainable utilization. Environment & Ecology 22 (Spl-

1) : 56-63.

Mahapatra, B. K., Vinod, K. and Mandal, B.K. 2004. Ornamental Fish of North Eastern

India – Its distribution and conservation status. Environment & Ecology 22 (3) : 674

- 683.

Mahapatra, B.K., Vinod, K. and Mandal, B.K. 2005. Export potentiality of native

ornamental fish from North Eastern Hill States of India with a note for development

of such fisheries. Environ. Ecol. 23(4): 780-786.

Mahapatra, B.K., Vinod, K. and Mandal, B.K. 2007a. Native ornamental fisheries in

Sikkim with its prospects and constraints.. Environ. Ecol. 25S(1): 125-128.

Mahapatra, B.K., Vinod, K. and Mandal, B.K. 2007b. Breeding and larval rearing of Labeo

gonius (Hamilton) under mid hill altitudinal region of Meghalaya. Environ. Ecol.

25S(1): 98-101.

Nair K. S. 2004. Scope of expanding ornamental fish culture and trade and role of MPEDA.

In: Ornamental fish culture and trade in Northeastern India (Eds. B. K. Bhattecharjya

and M. Choudhury). Work Proc. CIFRI, Brackpore, Kolkata.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

Training Compendium

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NURSERY REARING OF CARP FRY & FINGERLINGS AND GROW-

OUT CARP CULTURE WITH SPECIAL EMPHASIS ON POND

MANAGEMENT

R.K. Trivedi , S. K. Dubey & S. K. Rout

Department of Aquatic Environment Management

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

Introduction:

Carps are the mainstay of fish culture practice in India and these are the three Indian

major carps viz., Catla, Rohu and Mrigal together with three other exotic carps viz.,

Silver Carp, Grass Carp and Common Carp which contributes over 85% of the

aquaculture production of the country. In the recent years carp culture is gaining popularity

in various parts of the country. Both the Indian and Chinese carps are found to be well

suited for rearing in fresh water ponds as a major income generating enterprise. The

technological interventions during last three decades have led to increase the mean national

production levels in ponds and tanks from about 600 kg/ha to over 2,000 kg/ha. Higher

production levels of 6-8 tonnes/ha/year are being achieved by several farmers and

entrepreneurs in states like Andhra Pradesh, West Bengal, Punjab and Haryana. Successful

carp culture depends very much on the proper breeding and production of healthy fry and

fingerlings. Availability of required quantity of seed of the desired species at the

appropriate time is one of the main factors that lead to success of aquaculture operation.

The nursery rearing involve nurturing of 72-96 hours old spawn which have just begun to

eat and continues for a period of 15-20 days, during which they grow to fry of about 25-30

mm. These fry are further reared in another pond for a period of 2-3 months to raise the

fingerlings of about 100 mm in size.

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NURSERY REARING OF FRY AND FINGERLING

1. Nursery Pond Management

Small ponds of 0.02-0.10 ha with depth of 1.0-1.5 m are preferred for nurseries. Drainable

or non-drainable earthen ponds and cement cisterns are the different systems used for

nursery rearing of fry. The different steps involved in nursery rearing of fry are as follows.

1.1 Pre-stocking Pond Preparation

Eradication of aquatic vegetation: aquatic weed clearance is the first operation in pond

preparation. Abundant growth of vegetation is undesirable in fish ponds as they absorb

nutrients which lower the pond productivity, help in harboring the predatory and weed

fishes/insects which hinders the free movement of fish and netting operations. Generally,

manual methods are only used in nursery and rearing ponds, as they are shallow and small

in size. In bigger ponds mechanical, chemical and biological methods can be used for

eradication of aquatic weeds.

Eradication of predatory organisms: Dewatering and sun-drying the ponds or application of

suitable piscicides are the methods adopted for eradication of predatory, weed fishes and

other organisms. Before stocking of fish seed, application of mahua oil cake @ 2,500

kg/ha-m are suggested. The oil cake besides acting as piscicide also serves as organic

manure after decomposition and adds to natural productivity. Application of commercial

bleaching powder (30% chlorine) at dosage of 350 kg/ha-m of water is effective in killing

the fishes. The quantity of bleaching powder can be reduced to half with the combination of

urea @100 kg/ha-m, applied 18-24 hours before the bleaching powder application.

Control of aquatic insects: Aquatic insects and their larvae compete for food with the young

growing fish and also cause large-scale destruction of hatchlings in nurseries. Application

of soap-oil emulsion (cheap vegetable oil @ 56 kg/ha with 1/3 its weight of any cheap

soap) is a simple and effective method to kill the aquatic air-breathing insects. Kersoene

@100-200 litre or diesel @75 litre and liquid soap @ 560 ml or detergent powder @ 2-3 kg

per hectare water area can be used as substitute to make the emulsion.

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Pond fertilization: Planktons are the preferred natural fish food organisms that are produced

by fertilizing the culture ponds. The ponds used for seed production are first limed after the

removal of unwanted predatory and weed fishes depending on the pH of soil. After liming,

the ponds are treated either with organic manures such as cow dung, poultry dropping or

inorganic fertilizers or both, one following the other. Mixture of groundnut oil cake at 750

kg, cow dung 200 kg, and Single Super Phosphate 50 kg/ha is found to be very effective in

production of desired plankton. Half of the above amounts, after being mixed thoroughly

by adding water to make a thick paste are spread throughout the nursery 2-3 days prior to

stocking.

1.2 Stocking

After three days of hatching, the spawn are transferred to the nurseries. The stocking is

done preferably during morning time by acclimatizing them to the new pond environment.

The normal density of spawn recommended for earthen nursery is 3-5 million/ha. However,

higher densities of 10-20 million/ha can be followed in cement cisterns. In nursery,

monoculture of carp species is usually recommended.

1.3 Post-stocking Pond Management

The phase fertilization is done in 2-3 split doses during the culture period of 15 days as

discussed earlier. Finely powdered mixture of groundnut oil cake and rice bran at 1:1 ratio

by weight are provided as supplementary feed @ 6 kg/million for the first 5 days and 12

kg/million spawn per day for the subsequent days in two equal installments. With adoption

of scientific methods of rearing, the fry attain the desired size of 20-25 mm with survival of

40-60% in 15 days rearing period. Since nursery-rearing period is limited to 15 days, the

same nursery can be utilized for multiple cropping, at least for raising 2-3 crops in case of

earthen ponds and 4-5 crops in case of cements cisterns.

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2. Fry-Fingerlings Rearing Pond Management

Ponds of comparatively bigger in size than that of nurseries and preferably up to 0.2 ha area

is usually used for rearing pond, i.e., for rearing fry to fingerlings. The different

management practices involved are as follows.

2.1 Pre-stocking Pond Preparation

The management practices of pre-stocking pond preparation are same as discussed in

nursery pond management like clearance of aquatic weeds and eradication of predatory and

unwanted organisms, etc. The ponds are fertilized with organic manures and inorganic

fertilizers, the doses of which depend upon the type of fish poison used. If mahua oil cake

is used as fish poison, the amount of cow dung application is reduced to only 5 tonnes/ha,

cow dung is applied generally at the rate of 10 tonnes/ha. While about one third of the dose

is applied as basal dose 15 days prior of stocking, rest are applies fortnightly doses. Urea

and Single Supper Phosphate @ 200 kg and 300 kg/ha/year, respectively are also

recommended for fortnight application in split doses as inorganic fertilizer source.

2.2 Stocking of Fry

The normal stocking density of fry suggested for rearing ponds is 0.1-0.3 million/ha. The

rate of stocking mainly depends on the productivity of the pond and the type of

management measures to be followed. While nursery phase is limited to monoculture,

rearing phase involve polyculture of different carp species similar to that of grow-out

production.

2.3 Post-stocking Pond Management

Supplementary feeding is done that limited to the mixture of groundnut oil cake and rice

bran at 1:1 ratio by weight, non-conventional ingredients can also be used to compound the

feed. A feeding rate of 5-10% followed for fingerlings rearing. When grass carp or

common carp are stocked, duckweeds or aquatic macrophytes like Wolffia, Lemna and

Spirodela are to be selectively provided. Water levels of about 1.5 m depth should be

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maintained and other management measures and intermittent fertilization as mentioned

earlier are suggested. With adoption of scientific methods of rearing, the fingerlings attain

80-100 mm/8-10 g with a survival of 70-90% under rearing pond conditions.

GROW OUT CARP CULTURE

3. Carp polyculture

Production levels of 1-3 tonnes/ha/year can be achieved through carp polyculture in India

have been utilizing a huge amount of organic wastes with application of both organic and

inorganic fertilizers. Production levels of 4-8 t/ha/yr are obtained using a scientific

combination of both the feed and fertilizers. Ponds of 0.4-1.0 ha in size with water depth of

2-3 m are considered to be best for better management. The management practices

in carp polyculture involve environmental and biological manipulations, which can be

broadly classified as pre-stocking, stocking and post-stocking operations.

3.1 Pre-stocking Pond Preparation

A lucrative production can be obtained by making ponds weed and predator-free and

generating adequate natural food resources. Control of aquatic weeds and other unwanted

biota as well as improvement of soil and water quality are the important aspects connected

pre-stocking pond management. The detail regarding the control of predatory and weed

fishes have been discussed previously in nursery management.

3.2 Stocking of Ponds

Seeds of appropriate size are stocked after acclimatizing to the new habitat when pond is

ready after fertilization. Fingerlings of over 100 mm in size are recommended for stocking

in grow-out culture ponds. In intensive polyculture ponds, a size of 50-100 g is preferred

for stocking to realize higher survival of over 90% and better growth. Generally, a density

of 5,000 fingerlings is kept as a standard stocking rate per ha for carp polyculture for a

production target of 3-5 t/ha/yr. Stocking densities of 8,000-10,000 fingerlings/ha has been

used for production levels of 5-8 t/ha/yr. Higher targeted fish production levels of 10-15

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t/ha/yr are achieved by resorting to stocking at a density of 15,000-25,000/ha. Combination

of six species viz., Catla, Silver Carp, Rohu, Grass Carp, Mrigal and Common Carp has

been proved to be the ideal combination for carp culture in India. Catla and Silver Carp are

surface feeders, Rohu is a column feeder, Grass Carp is a macro-vegetation feeder, and

Mrigal and Common Carp are bottom feeders. A proportion of 30-40% surface feeders, 30-

35% mid water feeders, and 30-40% bottom feeders are commonly adopted depending on

the productivity of the pond.

3.3 Post-stocking Pond Management

Fertilization: 20-25% of the total amount of organic manures is applied as basal dose, a

fortnight before the stocking; the remaining amount is applied in equal installments on a

bimonthly basis. Other commonly used organic manures include poultry litter, pig/cow

dung, duck droppings, domestic sewage, etc. depending on the availability. Azolla, a

nitrogen-fixing macrophytes has been standardized as a biofertilizer for aquaculture at an

application rate of 40 t/ha/yr, proving the full complement of nutrients required for

intensive carp culture (100 kg nitrogen, 25 kg phosphorus, 90, kg potassium and 1,500 kg

organic matter).

Supplementary feeding: The supplementary feed in carp polyculture is usually restricted to

mixture of groundnut/mustard oil cake and rice bran. With the shift towards intensive fish

culture, other ingredients from plant and animal protein sources are being incorporated. To

hold these components in the feed together, pelletization is done, which in turn helps for

water stability and reduction of wastage. Grass carps are fed with preferred aquatic

vegetation (Hydrilla, Najas, Ceratophylum, duck weeds, etc.) kept in enclosures in selected

corners of the pond. Marginal vegetation, land grasses and other fodder, banana leaves and

vegetable refuse can also be used. Feeding preferably twice-a-day is suggested. Feeding is

done @ 5% of the initial biomass of stocking material for first month and further at sliding

scale from 3-1% in subsequent months, based on the fish biomass estimated at monthly

intervals.

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Water exchange and aeration: Aeration may be used artificially to enhance the

concentration of dissolved oxygen in ponds, especially required in intensive culture with

higher stocking density. Water exchange is another important activity, considered to be

crucial in intensive aquaculture. Due to continuous accumulation of metabolites and

decayed unutilized feed, the water quality get deteriorated, leading to slow growth of fish

species and often leading to outbreak of diseases. Thus, it is necessary to replace certain

amount of water at regular intervals, especially during later part of the culture period in

case of intensive culture practices.

3.4 Harvesting

Harvesting of fishes is usually done after a culture period of 10 months to one year.

However, fishes attaining the marketable size can be harvested periodically to reduce the

pressure of density on the pond and thereby providing sufficient space for the growth of

other fishes.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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BREEDING AND LARVAL REARING OF PANGASIUS SUTCHI

N.R. Chattopadhyay

Faculty of Fishery Sciences

West Bengal University of Animal and Fishery Sciences

5, Budherhat Road, Panchasayar, Kolkata-700094, India

Introduction

The main species of Pangasid catfishes recently adopted for culture with Indian Major

Carps are Yellowtail catfish (Pangasius pangasius) and Sutchi catfish (Pangasius sutchi).

These fishes were introduced into the farming system of Bengal from Thailand through

Bangladesh in 1994-95. Though carnivorous at an early stage, the fish are compatible with

Indian Major Carps from five days onwards and can grow to 3 kg/year on a balanced

diet1,2. These fish have already established their importance as profitable species in

aquafarming of Bengal. As a result of its remarkable growth rate (almost one kg in 90

days), now there is much enthusiasm among the fish-breeders and farmers of Bengal for its

artificial spawning and culture. The demand for its seed is increasing by day. In view of the

increasing demand for Pangasius sutchi seed we tested techniques for induced spawning

and larval rearing of this fish.

Technique for induced spawning

Brood fish were raised in farm ponds (area 2,500 m3) from fry stage using a high protein

balanced diet composed of cereal waste (25%), rice-bran (20%), mustard oil cake (15-20%)

broken grain (25%) and animal meat (10-15%). The diet was provided 2-3 times per day at

the rate of 5% of body weight. To check growth rate the percentage of animal meat was

reduced as per requirement. The fish attain sexual maturity at four years when they

normally reach a size of 7 kg. However, for the convenience of breeding the weight of

brood fish we used was restricted to 1.5 to 2.0 kg with intensive stocking. Males and

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females are easily distinguished particularly around April. Egg-bearing females are

identified by their big, soft and distended belly with swollen and reddish pink vent (Fig. 1).

Males could easily be identified by their reddish genital opening and oozing of milt, when

the abdomen is pressed3. As with clarid Catfish only carp pituitary extract (CPE) was used

as the agent for inducing spawning. The results were promising. There are also reports

regarding the successful use of human chorionic gonadotrophin, (HCG) and LRH-A in

combination3, 4. A stimulatory first dose of 1.5-mg CPE/ kg body weight was injected into

mature females (Fig 2). After 5-6 hours the second resolving dose of 6 mg CPE/kg body

weight administered to females. Males were injected at the rate of 1 mg CPE/kg body

weight at the same time as the second injection to female. In the case that female

broodstock failed to reach the peak of maturity, the stimulatory dose would be increased to

2-2 mg CPE/kg body weight. The resolving dose in such situations would be 9-10 mg

CPE/kg body weight. Males were given a single resolving dose of 2 mg/kg body weight at

the time of second injection to female. Variations in environmental temperature have a

strong effect on the effectiveness of the dose. When temperature rises above 300C less CPE

is required and more is needed when the temperature falls below 280C.

Breeding starts from April and continues until mid September. One brooder can be used at

least two times during the same breeding season. After injection the fishes were returned to

their respective cement tanks or hapa. Spawning occurs after an interval of 5- 6 hours. Both

natural spawning and stripping is possible, but as the eggs are adhesive in nature stripping

was considered best (Figs. 3 to 5).

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Pangasius catfish. This specimen comes from a farm in Myanmar, close to Yangon

Fig.1Mature female Pangasius sutchi Fig. 2 The first injection to the female

taken for injection.

Fig. 3. Stripping the female Fig. 4. Stripping the male

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Fig.5.Eggs and milt are mixed with a feather water is added

Fig. 6. Fertilized eggs are mixed with milk solution to remove their adhesive covering

We rinsed eggs in milk powder solution in aluminium hundi to remove the adhesive

gelatinous covering of the fertilized eggs (Fig. 6). We prepared the milk solution by adding

200 ml of milk in 30 liters of water for 20 minutes. Afterwards the fertilized eggs were

transferred to a Chinese hatchery.

Effectiveness of the technique

In all trials, the fish responded positively and ovulated within 5-6 hours after the second

injection. The fertilization rate ranged from 95-100%. The fertilized egg doesn‟t swell as

with carps and hatched within 24 hours at temperature ranges between 30-320 C.

Temperature was a prime factor for fertilization and hatching. There are several other

reports of the successful breeding of P. sutchi in Indonesia and Thailand5. According

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Saidin and Othman4 the hatching period ranged between 24 to 26 hours at a water

temperature of 28-320C with ovulation occurring in between 70-80% and with a survival of

hatchings from 30-45%. Milt from one male is sufficient to fertilize the eggs of three to

four females. The dry method of egg fertilization was followed. They also found that the

hatchlings became cannibalistic if sufficient food is not available after 3 days of hatching.

We fed our hatchlings on lactogen for the first 48 hours. The hatchlings become

carnivorous from about 72 hours and at this stage weigh 500 mg. We fed earthworm dust

three times day continuing up to 5-8 days. After 10 days we fed soyabean dust as

supplementary feed. Afterwards we transferred the hatchlings to a rearing pond with natural

feed.

References

(1) Rahaman, M.K., Mazid M.A., Rahman, M.A. and Akhter J.N., 1991. Formulation of

quality fish feeds from indigenous raw materials and its effect on the growth of Catfish

Pangasius pangasius (Ham.). J. Zool. 6: 4 1-48.

(2) Rahaman, M.K., Akhter, J. N., Mazid, M.A. and Halder, C.G. 1992. Culture Feasibility

of exoitic catfish Pangasius sutchi (Fowler) in Freshwater Ponds of

Bangladesh. J. Inland Fish. Soc. India. 25 (2): 26-30.

(3) Rahaman, M.K., Akhter, J. N., Mazid, M.A. and Halder, C.G. 1993. First record of

Induced Breeding of Thai Panyas, Pangasius sutchi (Fowler) in Bangladesh J.

In land Fish. Soc. India. 25(2): 26-30.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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STATUS OF FISH DISEASES IN WEST BENGAL

Dr Gadadhar Dash

Department of Aquatic Animal Health

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

INTRODUCTION

Table 1. West Bengal Fisheries at a glance

Water Resources

Coastal Line 158 Km

Rivers and Canals 2,526 Km

Reservoirs 0.17 lakh ha

Tanks and Ponds 2.76 lakh ha

Flood plain lakes and derelict waters 0.42 lakh ha

Brackish water 2.10 lakh ha

Fish Production

- Marine 1,86,790 tonnes

- Inland 13,23,120 tonnes

- Total 15,09,910 tonnes

Shrimp Production

- Area developed 51,659 ha

- Area utilized 47,488 ha

- Production 33,685 tonnes

- Productivity 0.71 MT/ha/year

Scampi Production

- Area developed 4825 ha

- Area utilized 3325 ha

- Production 1,725 tonnes

- Productivity 0.52 tonnes/ha/year

Potential for Fish production enhancement in floodplain wetlands

- Area 42,500 ha

- Existing Production 9560 tonnes

- Potential Production 53,150 tonnes

- Gap 43,590 tonnes

- % increases 455.96

Beels (Throughout India)

- Potential Production levels 1,000 – 1,500 Kg/ha/year

- Present level 100 -150 kg/ha

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Crustacean Fisheries (2007)

- Penaeid Shrimp Landing 11,224 tonnes

- Non Penaeid Shrimp Landing 15,148 tonnes

- Lobster Landing 91 tonnes

- Crab Landing 1,695 tonnes

State Fish Tenulosa Ilisha (Hilsa)

Source: Handbook of Fish and Fisheries, 2011 edition ICAR publication.

Aquaculture has become the worlds‟ fastest growing food-producing sector, with a

growth rate of 10% annually since 1984. Asia produces about 91% of the worlds‟ total

aquaculture production with China, India, Japan, the Republic of Korea, the Philippines,

Indonesia and Thailand as top producers within Asia. In India freshwater aquaculture has

made notable progress in recent years, and contributed about 3/4th of the total fish

production in the country. Freshwater aquaculture depends mainly on carp culture practices

that account for around 80% of the total inland fish production and have proved sustainable

at different levels of production over the years. Production comes from over 2.25 million ha

of tanks or ponds, 1.3 million ha of oxbow lakes, 3 million ha of reservoirs and 1.2 million

ha of coastal brackishwater area.

India is the 4th largest producer of fish in the world and is 2nd in inland fish

production. India‟s share in the world‟s fish production has increased from 3.2% in 1981 to

4.5% at present (Ayyappan and Dewan, 2006). Fish production has increased from a level

of 0.75 million tonnes in 1950-51 to 6.4 million tonnes in 2003-04 against harvestable

potential of 8.4 million tonnes registering an average growth of 4.29% over the same

period. Increase in productivity and production of fish is one of the accepted programmes

during the 12th Five-year Plan. Aquaculture production in India was 8.03 million mt in

2010-11, with 5.07 million mt coming from inland fisheries and the rest (2.96 million mt)

from marine sector. India is one of the largest producers of cultured shrimp. The cultured

shrimp contribute considerably to the total shrimp production and shrimp exports of our

country. It is reported that India has around 1, 41,591 ha of total water spread area under

shrimp culture. In West Bengal alone, the potential area for shrimp farming is estimated to

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be 4, 05,000 ha against the India‟s potential area of 11, 90,900 ha. West Bengal is the 2nd

largest producer of cultured shrimp in India next to Andhra Pradesh.

West Bengal has 19 districts, with an area of 88,551 sq km. The State is endowed

with remarkable variation in physiographic resources from sea to snow having an elevation

from 5 m in the south to 3,658 m from the main sea level in the north. Fisheries resources

of West Bengal are presented in Table 2.

Table 2 - Freshwater fishery resources of West Bengal (Source: DFAARFH, 2006)

2. Type of

fishery

Total resource

(in lakh ha)

Area under culture

(in lakh ha)

Percentage of area

under culture(%)

Ponds/ Tanks 2.76 2.20 79.71

Beel and Baor 0.41 0.21 51.21

Reservoir 0.16 0.03 18.75

River 1.72 - -

Canal 0.80 - -

Sewage fed 0.04 0.04 100.00

Fisheries development in this State has made considerable progress over the

successive 5-year plan period. The fish production has increased from 0.37 lakh tonnes in

1980-81 to 11.69 lakh tonnes in 2004-05 with average annual growth rate of 0.50%. In

relation to all India table fish production, West Bengal has a share of 18.36%. While in

inland sector, its share was 28.93%. West Bengal is the highest producer of fish seeds,

meeting the all India requirement of as high as about 62%. On the inland fisheries front, the

State of West Bengal occupies the first position in fish production producing 10.90 million

tonnes. There are about 22, 12,019 fishermen who are engaged in inland fisheries activity.

Most of the West Bengal farmers have now adopted „multiple stocking and multiple

harvesting‟ technique in order to maximize the inland fish production. Major carps

contribute to about 90% of the total freshwater aquaculture production of West Bengal.

Freshwater prawn, Macrobrachium rosenbergii, locally known as golda chingri, has high

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potential for culture as an alternate culture species for Penaeus monodon in all freshwater

tanks and ponds (DFAARFH, 2006).

Freshwater aquaculture in West Bengal depends mainly on carp-culture practices

that have proved sustainable at different levels of production over the years. Diseases of

varied etiology are, however, a serious constraint to the success of many of the freshwater

culture systems. With the intensification of culture, fish health problems have become very

common in West Bengal carp culture systems. There are several aquatic animal health

problems in different culture systems that influence production from such systems.

Infectious diseases of cultured freshwater carps are one of the major problems to successful

aquaculture industry. Several bacterial, parasitic and fungal diseases have been documented

in freshwater culture systems of West Bengal, which may, thus, have serious socio-

economic impacts. Aquatic animal health problems in pond culture and their impacts on

yield are well known, but are not often quantified due to the difficulties in collecting

accurate and reliable quantitative information. Several earlier studies regarding incidence of

freshwater fish diseases in West Bengal confirmed that epizootic ulcerative syndrome

(EUS) was the most common disease, which has a significant impact on the

socioeconomics of the fishermen. The EUS was found to be epidemic in almost 50% of the

freshwater farms of West Bengal since the decade of ninety (Bhoumik et al., 1991; Das,

1997; Paria and Konar, 1999; Biswas, 2002). The EUS not only incurred a loss of 40% of

the stock in producer level, but also affected the fish trade, as about 90% fish traders were

affected due to marketability and fall in selling price.

Prevalence of fish diseases in West Bengal

Paria and Konar (1999) reported the prevalence of fish disease in West Bengal.

Among the freshwater fish diseases, EUS caused significant economic loss. Argulosis,

malnutrition, gill rot, dropsy, tail and fin rot, tumour and fungal diseases were also reported

but not as severe as EUS. They identified that the stress of environmental parameters

(properties) were responsible to induce fish diseases and correlated the occurrence of fish

diseases with several pond management practices. According to the survey, the percentage

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of pond affected by EUS ranged from 32.68% to 72.72%, argulosis 0.81% - 9.80%,

malnutrition 9.69% - 32.30%, gill rot 9.10% to 34.37%, dropsy 3.33% to 14.40%, tail and

fin rot 2.43% to 6.52%, tumour 0.85% - 7.28% and fungal diseases 1.12% - 2.19% from

different districts of West Bengal. Biswas (2002) reported 13.6%, 23.0% and 50.0%

incidence of EUS in culture ponds, public ponds and beels, respectively of Nadia, 24

Parganas North and South districts of West Bengal.

Mishra and Das (1993) reported Trichodina reticulata from the gills of C. catla at

Sheoraphuli locality of West Bengal; where as Pagarkar and Das (1993) reported

Thelohanellus caudatus and Myxobolus serrata from caudal and anal fins of L. rohita and

gill arch of C. carpio. Ghosh et al. (1987) reported Dactylogyrus spp in C. catla from

Hooghly district. Das (2003) recorded five different types of helminth groups such as

monogeneans (Gyrodactylus sp. and Dactylogyrus sp.), digeneans (Diplostomum sp.), cestodes

(Caryophyllaeus sp.) nematodes (Spirocamallanus sp. and Anisakis sp.) and acanthocephalans

(Hypoechinorhynchus sp.) as dominant helminth parasites in the catfishes of beels from Nadia

district. She also showed the species specificity site of infestation as well as seasonal

pattern of helminth infestation in catfishes. Ghag (2004) and Saha (2005) reported five

different types of helminth groups such as monogeneans (Gyrodactylus sp. and Dactylogyrus

sp.), Digenians (Heterophyes heterophyes, Clonorchis sp.), cestodes (Caryophyllaeus sp.),

nematodes (Camallanus sp. Indocucuiianus sp. Rhabdochona sp.) and Acanthocephalans

(Pallisentis sp.) as the dominant helminth parasites in the carps from freshwater ponds,

hatcheries and market complexes of Nadia, 24 Parganas North and Howrah. They also

showed the species specificity, site of infestation as well as seasonal pattern of helminth

infestation in carps. Abraham et al. (2004) studied the bacterial flora associated with tail rot

or fin rot of Carassius auratus, Xiphophorus helleri and hemorrhagic ulcers of Clarias spp.

and isolated Aeromonas spp. Pseudomonas spp. and gram positive rods. According to

them, ciprofloxacin was the most effective in inhibiting bacteria at 0.05-0.10 µg/ml levels.

The multiple antibiotic resistances were seen in 21% of the bacterial isolates.

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3. Dissection and Analysis of the problems of West Bengal fish farmers

The Department of Aquatic Animal Health, FFSc, WBUAFS made a survey on the

health management issues of freshwater fish farmers in 11 districts of West Bengal and

information collected are presented below:

The details of fish farming practices and species cultured in West Bengal

About 64% of the surveyed farmers practiced a semi-intensive or intensive type of

aquaculture. This intensification mainly in terms of very high stocking density (about 2

lakh spawn/bigha, 50,000 fry/bigha and 5000 fingerlings/bigha) with external feed input.

However there was no water exchange or planned feeding schedule, regular health on water

quality, monitoring. The results indicated the reluctance of the farmers in adopting

scientific fish farming. Interestingly there was no trend of practicing monoculture. All the

farmers adopted polyculture with some kind of integration mainly with horticulture and

duck rearing. However, it was observed that majority of them ventured into integrated

farming without knowing the actual technical benefit. About 8.97% of the interviewed

farmers were involved in sewage fed aquaculture. They usually treated the raw sewage

before letting into the pond with lime at the rate of approximately 25 kg/bigha after that

adding 5-7% raw sewage to the existing treated water (dilution method) in 10 to 15 days

interval.

All the West Bengal farmers cultured Labeo rohita and Catla catla. Most of the

farmers also cultured Cirrhinus mrigala, Hypophthalmychthys molitrix, and Labeo bata.

Besides, species like Cyprinus carpio, Ctenopharyngodon idella, Labeo calbasu and

Macrobrachium rosenbergii were also cultured. Labeo rohita, Catla catla, Cirrhinus

mrigala and Labeo bata are highly popular food fish in fish loving West Bengal.

Hypophthalmychthys molitrix and Ctenopharyngodon idella were cultured due to their

faster growth rate. Oreochromis mossambicus, Tilapia niloticus, Puntins javonicus were

also widely cultured because of their high proliferation rate. In spite of the ban imposed by

the State Government Clarias gariepinus and Arichthys nobilis were also cultured by

3.85% and 34.62% or the respondent farmers.

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The unique characteristics of West Bengal freshwater fish culture system was

repeated stocking of fish seeds (80.77%) in water bodies. Due to the high demand of

advanced fingerlings to juvenile size fish in West Bengal market, farmers need to harvest

such fish size groups and replenish the harvested stock with fresh fish seeds to maintain the

required stocking density in the pond. The usual stocking density in nursery, searing and

stocking ponds with normal productivity status are 6 million spawn/ha, 0.3 million fry/ha

and 5000 fingerlings/ha respectively (Jhingran, 1991). But in West Bengal freshwater fish

farming system the fishes are usually stocked at a very high density. About 21% of the

farmers stocked 1000-5000 fingerlings/bigha about 23% of the farmers stocked 5000-2500

fry/bigha and about 25% of the farmers stocked more than 2.5 lakh hatchlings /bigha. This

high stocking density was mainly to achieve maximum productions and to compete in a

highly competiting market often ignoring the productivity status of the pond. Majority of

the farmers (about 76%) considered that, they received a good quality seed whereas about

24% farmers received average quality seed. the farmers graded the seeds from reputed

hatcheries as either or „good‟ average quality and from other sources mainly from local

non-reputed hatchery as „bad‟ quality. Almost all the farmers (about 88%) acclimatized

their fish seed before stocking. About 68% of the farmers did not treat their fish seed before

stocking. About 29% of the farmers treated their seeds with disinfectants like salt or

potassium permanganate. Use of antibiotic for treatment of fish seeds before stocking was a

rare practice.

Acclimatization is the process of adjusting shortly with the new environment when a

fish stock is released to a new environment from another environment. If the fishes are

stocked without any acclimatization, it will face an environmental „stock‟. This sudden

stress impairs the normal homeostatis on of fish and the pathogens get a chance to cause

disease (Sneiszko, 1973). About 54% of the farmers experienced negligible or no mortality

during acclimatization and about 35% of the farmers faced a mortality of about 1-5%. Most

of the farmers were not at all bothered of this mortality as they normally receive some extra

seeds from the sellers as gift neutralizing the loss during transportation and acclimatization.

Training Compendium

57

Though natural food contributes to the nutrition (De-Silva and Anderson, 1992) of

the cultured fish in semi-extensive and extensive culture systems, the exogenous supply of

artificial food is essential to supply nutrients, which may be deficient in natural food.

However, application of artificial feed affects water quality criteria more than any other

management factors. Feeding of fish at 2-5% of the body weight is recommended based on

natural productivity of fish pond (Sarkar, 2002). Among fish feeds, oil cake (84.62%)

mainly mustard oil cake was favoured mostly by the West Bengal fish farmers because of

its easy availability and nutritional quality. Simultaneously their increasing market prices

were also a major concern among the fish farmers and most of then were searching for a

low cost nutritional fish feed. Rice/wheat bran husk were also quite commonly used by the

fresh water fish farmers of West Bengal. Farmers grew duck weed and Eichornia at least

some part of the pond. After an interval they used to reserve weeds. Sometimes farmers

used duck weed procured from external source and applied either by composting or directly

broadcasting into pond. However, about 10% of the farmers were entirely dependent on

ponds natural production. Manuring was not a common practice, as about 41% farmers did

not apply any type of manure/fertilizers possibly due to already existing natural production

or from a fear of disease transmission particularly white spot on gills or argulosis from

organic manure input. About 8% of the farmers applied green manure prepared on a pit by

the side of the pond. Almost half of the farmers monitored water quality regularly mainly

by visual observation where as about 59% of the farmers monitored fish health mainly

during netting operation.

Table -3. Most frequently encountered diseases of fishes and prawns those cause heavy economic losses and their seasonal distribution in Indian water.

Diseases Species affected Stage of fish Seasonal distribution

Bacterial diseases Summer Rainy Winter

Aeromoniasis Freshwater fishes All stages Yes Yes Yes

Edwardsellosis All freshwater and Mostly fry and No Yes Yes

some brackish water fingerlings

fishes

Training Compendium

58

Table- 4. Summary of health problems encountered in West Bengal freshwater fish

farms (2006-2011) Health

problem

Species

affected

mostly

Stage

affected

Season Mortality

rate (%)

Treatment

Chemical Success

Ulcer C. mrigala,

L. bata

Channa

spp

Fingerlings,

Juveniles

Winter,

post

monsoon

Few fish

daily/weekl

y

KMnO4,

CIFAX,

Lime,

curine,

metacid

Partial

Argulus L. rohita,

C. catla,

C. mrigala

Fingerlings,

Juveniles,

Adult

Round the

year

No

mortality

Nuvan,

Cleaner

Partial

White spot C. catla Fry to Winter Few fish Salt, Partial

Bacterial gill All freshwater fishes Grow out and No No Yes

disease Adult

Colunmaris disease All freshwater fishes All stages Yes No No

Vibriosis Freshwater prawn All stages Yes Yes No

shrimps All stages Yes Yes Yes

Viral diseases

White spot disease Penaeus monodon All stages Yes Yes Yes

Monodon Baculo- Penaeus monodon All stages Yes Yes Yes

virus disease

White tail disease Macrobrachium Post larvae and Yes Yes Yes

rosenbergii juvenile

Fungal diseases

Saprolegniasis All freshwater fishes All stages No No Yes

Parasitic diseases Argulosis All freshwater fishes Adult No Yes Yes

with scales, Labeo rohita more susceptible

Lemaeasis All freshwater fishes Adult and No Yes Yes Juveniles

Myxosporidiasis All freshwater fishes All stages Yes Yes Yes

Dactylogyrosis All freshwater fishes Adult No Yes Yes

Training Compendium

59

on gill advanced

fry

weekly Lime

Stunted

growth

C. mrigala,

L. bata,

C. catla

Fry,

fingerlings

Rainy No

mortality

Mohua oil

cake

Successf

ul

Tail/fin rot L. rohita,

C. catla,

C. mrigala

Fingerlings Summer No

mortality

Salt,

KMnO4

Successf

ul

Dropsy C. mrigala

C. catla

Fingerlings,

Juveniles

Winter,

Summer,

Few fish

weekly

KMnO4,

Salt

Not at all

Hemorrhage

s

L. rohita

C. catla

C.mrigala

Fingerlings,

Juveniles

Winter Few fish

weekly

KMnO4,

Lime

Successf

ul

Table- 5. Prevalence of diseases in general and clinical symptoms in ornamental fish,

Carassius auratus , (2006-2011).

Gross and clinical Signs Amtala, South 24

Parganas

Santragachi, Howrah Arambagh, Hooghly

Season Varieties Season Varieties Season Varieties

Anorexia

Crustacean infection

Distended abdomen

Dropsy

Dorsal rigidity

Emaciation

Exophthalmia

Faded pigment

Fin rot / damage

Fungal infection

Furuncles

Gill damage

Hemorrhaging at base of

fins

Hemorrhaging eye

Hemorrhaging fins

Hemorrhaging mouth

Hemorrhaging opercula /

gills

Hemorrhaging skin

Protozoan infestation

Protruded anus / vent

Sloughing off of scales

Sluggish behaviour

Spiral / erratic movement

S, W

S, M

S, W+

M+

M+

W

W+

W

M, W,

W

S, W+

W+

S

S+, W

S

S

S+

S

S, M

S, M, W

M, W

M, W

S+

S+

S+

All

All

R, O

O

O

All

R, O

R, O

All

R, O

O, Z

All

R, O

R, O

R, O

R, O

R, O

R, O

All

All

All

All

R, O

All

All

-

S, M

S, W+

R+

M+

-

W+

-

M, W,

W

S, W+

W+

S

S+, W

S

S

S+

S

S, M

S, M, W

M, W

M, W

S+

S+

S+

-

All

R, O

O

O

-

R, O

-

All

R, O

O, Z

All

R, O

R, O

R, O

R, O

R, O

R, O

All

All

All

All

R, O

All

All

S, W

S, M

-

-

-

S, W

-

W+

S, M

W

W

W+

S+

-

S

-

S+, W

S

S, M

S, M, W

S, M

M, W

S+, W

W

S

All

All

-

-

-

All

-

R, O

R, O

R, O, B

Z

All

R, O

-

R, O

-

R, O

R, O

All

All

R, O, L

All

R, O, L

R, O, L

R, O

Training Compendium

60

R: Red cap, B=Black, O: Oranda, L: Lion head, Z: Shubunkin, M: Monsoon (July –

September), S: Summer (April June), W: Winter (November – January); +: More; -: Not

observed.

0

20

40

60

80

100

Tra

nsport

Po

ach

ing

Silta

tio

n

Dis

ease

Fin

an

cial

Pri

ce

(mark

et) …

Man

ag

em

en

t …

Inun

dat

ion

due to

…

Oth

ers

28.21

48.71

25.64

82.05

50.00

30.7725.64

51.28

32.05

Resp

on

dents

(%

)

Fig. 1 - Major problems encountered by the fish farmers of West Bengal

0

10

20

30

40

50

60

70

Ulc

ers

Tail/fin

ro

t

Dro

psy

Arg

ulu

sin

…

Wh

ite …

Aq

uatic …

Gulp

ing a

ir

Big

/defo

r…

Hem

orr

h…

Stu

nte

d …

67.95

37.18

50.00

37.1830.77

25.64

43.59

25.64

35.9

51.28

Resp

on

dents

(%

)

Fig. 2 - Major diseases / abnormalities that cause production loss in West Bengal

Stunted growth

Tail rot / erosion

Ulcers

White nodules on gills /

skin

White spots on head

Other abnormalities

S+

M, W+

S+

S, M, W

R, O

All

O

All

S+

M, W+

S+

S, M, W

R, O

All

O

All

S+, M

W

S+

S, M, W

R, O, L

B, Z

B, Z

All

Training Compendium

61

Dropsy was noticed to be a very common disease in freshwater fishes of West

Bengal, although only a fraction of total stock was affected. It was common during winter

and summer seasons among the fingerlings and juveniles of C. mrigala and C. catla with

affected fishes dying regularly. Although farmers used a variety chemicals like salt and

potassium permanganate, they were unsuccessful and resorted to remove the affected fishes

and through out of the pond. Hemorrhages or red spots of fingerlings and juveniles stages

of IMC in winter season were also a common problem. Few fishes died weekly although

farmers got success to get rid of the problem with application of potassium permanganate

and lime.

612.34

451.33

100

73.71

0

25

50

75

100

0

200

400

600

800

1000

Expected Production Actual Production

Pe

rce

nta

ge

Pro

du

ctio

n (

kg

/ b

igh

a)

Average expected and actual fish production of respondent

West Bengal farmers (7.5 bigha = 1 ha)

Table 6- Parasitic Diseases in West Bengal.

Fish Species Parasites Season

Carps

Catla catla > L. rohita and C. mrigala. Argulus ……….... Summer

Catla catla > L. rohita and C. mrigala. Helminth groups such as…..Summer

Monogeneans (Dactylogyrus sp

&Gyrodactylus sp.),

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62

Digeneans (Heterophyes heterophyes),

…………. Monsoon

Cestodes (Caryophyllaeus sp.),

Nematodes (Camallanus sp.)

Acanthocephalans (Pallisentis sp.)

Catfishes:

(Mystus vittatus, Clarias batrachus

and Heteropneustes fossilis). Helminth groups such as

Monogeneans (Gyrodactylus sp.,

Dactylogyrus sp.), …..................Winter

Digeneans (Diplostomum sp.)….Winter

Cestodes (Caryophylleaus sp.),

Nematodes (Anisakis sp. and

Spirocamallanus sp.)

and Acanthocephalans

(Hypoechinorhynchus sp.)

Exotic Carps:

(Hypothalmicthys molitrix,Ctenopharyngodon idella

and Cyprinus carpio)

Protozoans ( Trichodina sp,Zoothamnium

sp, Vorticella sp, Epistylis sp,

Chilodonella sp)... Winter

Nematodes ( Camallanus sp,

Indocucullanus sp. )…………. Winter

and Acanthocephalans

USE OF CHEMICALS IN AQUACULTURE

The various chemicals used in grow-out farming and hatchery operations in freshwater

aquaculture in India can be classified into the following broad categories: water/soil

treatment products, disinfectants, piscicides, herbicides, organic fertilizers, inorganic

fertilizers, feed additives, therapeutants and anesthetics.

In freshwater aquaculture, it is common practice to treat the pond waters for

mineralization of organic matter, for adjusting pH, and for disinfection. The chemicals

used in this regard are lime in the form of lime stone (CaCO3), slaked lime (Ca(OH)2)

or unslaked lime(CaO). Dried ponds are also sterilized using active iodine or potassium

permanganate (KMnO4). Soil conditioners that contain high numbers of sulfur-

degrading bacteria and organic matter-decomposing bacteria are also used by some

intensive shrimp culture farms. Health stone, zeolite,or porous aluminium silicate is

applied along with lime to re-activate the soil for stabilizing algal growth and absorbing

fouling materials.

Training Compendium

63

Disinfectants

Common disinfectants used are sodium hypochlorite, benzalkonium chloride (BKC),

calcium carbide, Na-EDTA, and zeolite. These are used mostly in hatcheries and, to a

limited extent, in grow-out ponds.

Piscicides

In both freshwater and coastal aquaculture, eradication of unwanted predatory fishes is a

commonpre-stocking management practice. The common fish toxicants used are mahua

oil cake, teaseed cake, other plant derivatives and anhydrous ammonium substances.

Herbicides

Aquatic weeds are of common occurrence in fishponds in the country and are

undesirable, as theypose serious problems by upsetting the oxygen balance and

removing nutrients from the aquaticsystems. The common herbicides used for

controlling aquatic weeds are 2,4-D; Dalapon; Paraquat; Diuron; ammonia; and many

others.

Organic Fertilizers: Use of organic manure in fish culture is an age-old practice. The

manure used comes mainly from farm animals, the commonly used manures being cow

dung, pig dung, poultry droppings, etc. Cattle manure and poultry droppings contain

nitrates at the 0.5 % and 1-15% levels and phosphates at the 0.2 and 0.4% levels,

respectively. The application of raw cow dung slurry helps to boost diatom bloom

(Sarkar 1983). In modified extensive shrimp-culture ponds, 1,000 to 3,000 kg ofcow

dung/ha is applied initially. It is followed by application of two dosages of 200 to 400

kg of cow dung on the 8th and 14th d, respectively. Poultry droppings contain higher

quantities of soluble salts, inorganic substances and organic products than does cow

dung, ensuring quick zooplankton production. In semi-intensive carp culture, large

amounts of cow dung are applied toincrease the fertility and consequent natural

productivity of the ponds. Natural food provides 50% of the food requirement in such

carp culture ponds.

Inorganic Fertilizers

Considerable quantities of nutrients are removed from the pond ecosystem through the

harvested fish crop. Hence, for proper management of pond soil and water, these

elements need to be replenished from external sources. The fertilization schedule is

prepared on the basis of the fertilitystatus of the soil. Soils with available nitrogen of

>50, 25-50, or <25 ppm; and available phosphate content of >6, 3-6, or <3 ppm are

classified as “high,” “medium” and “low,” respectively. The application rate of the

different nitrogenous and phosphate fertilizers varies with culture practice and the

nature of the fertilizer used. The doses of fertilizers applied for both carp culture and

Training Compendium

64

shrimp culture are presented in Table 1.

Feed Additives

With the intensification of aquaculture practices, there is a shift from using

supplementary fish feeds comprised of agricultural wastes and by-products to using

complete feeds developed to meet the complete nutritional requirements of the species

cultured. These feeds usually have other dditives in the form of pigments, vitamins,

chemo-attractants, and preservatives, like mold inhibitors and antioxidants.

Therapeutants

There is an increasing occurrence of disease caused by parasitic, fungal, bacterial, and viral

infectionsin both hatcheries and grow-out farms. In the recent past, India has witnessed

three major outbreaks of disease. The first to strike was the dreaded epizootic ulcerative

syndrome (EUS) in freshwater cultured species. This was followed by yellowhead-virus

disease and whitespot-virus disease in shrimp farms. The outbreak of these diseases

rendered severe blows to the aquaculture industry in the country, creating the need to use

therapeutants in both the freshwater carp industry and in shrimp culture.

Anesthetics

The use of anesthetics in aquaculture in India is rather limited. They are sparingly used,

particularly in the long distance transport of broodstock and fish seed.

Information on the uses, methods of delivery, doses, frequency of application, and other

aspects for chemicals commonly used by the Indian aquaculture industry is presented in

Tables 1-4. Information is presented separately for freshwater aquaculture and coastal

aquaculture. Information on the use of chemicals other than therapeutants in the

freshwater sector is presented in Table 1, whereas that for therapeutants is given in

Table 2. The use of chemotherapeutants in freshwater aquaculture is rather limited and

has gained significance only since the outbreak of EUS a few years ago. In carp

hatcheries, their use is also limited.

Training Compendium

65

Table 1. Use of chemicals (other than therapeutants) in freshwater grow-out culture and

hatchery systems in India.

Item Purpose Doses Mode of

Application Remarks

I. Soil and water

treatments

Quick lime

Correcting pH,

disinfectant 400 to 2000 kg/ha Dissolved in water and

broadcast over pond

surface

Basal dose of 50%.

Remaining in equal

monthly installments

Mineralization 400 kg/ha Dissolved in water and

broadcast over pond

surface

Applied at the time

pond preparation Andbroadcast over of pond preparation pond surface

II. Disinfectant

Bleaching powder Disinfectant 25-30ppm Broadcasting/water

solution

Toxicity lasts 7-8 days

III. Piscicides Mahua oil cake(MOC) (Basia latifolia)

Piscicide

(4-6% saponin)

200-250 ppm

Soaked in water and spread over water surface

Toxicity lasts 15-20 d,

after which it acts

Teaseed cake

(Camellia sinensis)

Piscicide 75-100ppm

Soaked in water and spread over water surface

As fertilizer,Toxicity

lasts 10-12 d, after

which it acts

Item Purpose Doses Mode of

Application

Inorganic fertilizers (kg/ha)

A. Nitrogenous Fertilization Sprayed or fertilizers distributed over Urea 150-300 water surface Ammonium

sulfate 300-600

Calcium

ammonium

nitrate

300-600

B. Phosphate Sprayed or

fertilizers distributed over Single super

phosphate

15 0-400 water surface

Triple super

phosphate 50-150

Training Compendium

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Table 2. Use of chemotherapeutants in freshwater aquaculture and hatchery systems in India

(from Rao et al. 1990).

RECOMMENDATION

Based on the management practices followed by the West Bengal fish farmers and their

association with the infectious disease outbreak, the following interventions can be drawn.

1. Construction and raising up of pond embankment above the flood level to prevent

the entry of flood water.

2. Pen culture can be adopted in vast water bodies like beels

3. In sewage fed ponds or bheries, the water treatment before introducing it into the

culture pond is vital.

A. Parasitic diseases

Oxytetracycline Myxobolus spp. 5 gm/ Supplemented Prevents secondary

100 kg fish in the feed bacterial infection Sodium Epistylis spp., 20-5 0 kg/ha 2-3 installments

chloride Zoothamnium spp. at 4-d interval

Malathion/ Dactyl ogyrus spp. 0.2 ppm 2-3 times at 4-d Pond water application Dichlorvos Gyrodactylus spp. interval Argulus spp., 0.15-0.25 ppm 2-4 installments Lernaea spp., (Malathion) at 4-7-d interval

Ergasilus spp. 0.05-0.1 ppm (Dichlorovos) Gammexane As above Immersion treatment

B. Bacterial/fungal diseases

Sulphadiazine Surface 5 gm/ Applied for 7 d Water dispersible Powder + Trimethoprim ulcerative and 100 kg

systemic type

(Aeromonas hydrophila) Chloro- 7 gm/100 kg ---do--- Supplemented in feed

tetracycline

Oxy-

tetracycline

Columnaris

disease

7-10

gm/100 kg Applied for 10 d Supplemented in feed

Nitrofurans Microbialgilldisease 10 gm/100 kg Immersion treatment

Trimethoprim 5-7 gm/100 kg

Copper

sulfate

Saprolegnia spp.,

Branchiomyces 0.2-0.5 ppm 2-3 installments

at 3-4 d interval Immersion treatment

Item Purpose Doses Mode of

Application

Remarks

Training Compendium

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4. Farmer‟s training on aquaculture; fish health management is highly needed.

Involvement of Non Govermental Organisations (NGO‟s) and educational institutes

in imparting training is highly needed.

5. Farmers should go for draining their ponds ideally once a year or at least once in

two years, particularly during post winter season.

6. Fish seed should bought directly from hatchery, checking the seed health on the

hatchery itself.

7. Stocking density of hatchlings <2.5 lakh/bigha, for fry <25,000/bigha and for

fingerlings <1000/bigha is recommended with multiple stocking and multiple

harvesting practices.

8. Winter is the most common period of infectious disease outbreak. Particular

measures should be therefore should be taken at this time.

9. The insurance company should come forward in fresh water fish culture also,

especially to guard the stock loss due to diseases and flooding.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

Training Compendium

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NURSERY AND REARING POND MANAGEMENT

Dr. S. K. Das

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

Introduction:

Preparation and maintenance of nursery, rearing and stocking ponds are important steps in

carp hatchery management. Carp post larvae and fry are delicate and unprepared or poorly

maintained ponds may lead to virtual decimation of the stocked materials for various

reasons. The purpose of nursery and rearing pond preparation before stocking and

maintenance is not only to remove the cause of poor health of the stocked material but also

to optimize good husbandry factors for rearing the young of the species concerned. Before

coming into the subject of nursery and rearing pond management, let us discuss the various

causes of fish seed mortality. This will be helpful to properly manage the said ponds and to

have better survival percentage.

Factors of fish seed mortality:

Before discussing nursery pond management, factors that cause early stage mortality of

fish, poor growth and ill health should be discussed. The main reasons behind the above

are as follows:

i) Physico-chemical incompatibility of the water of the hatchery and that of

nursery pond into which post-larvae are released and also disharmony of the

waters of the nursery and rearing ponds.

ii) Lack of adequate amounts of the appropriate kind of fish food organisms in

nursery and rearing ponds.

Training Compendium

69

iii) Predatory aquatic insects and other unwanted biota, which naturally harbour

in all freshwater bodies.

iv) Predatory fish, especially the young of the catfish, murrels and featherbacks

which directly prey upon the fish.

v) Cannibalism especially when post larvae and fry of different sizes are stocked

together.

vi) Sudden fluctuation of water temperature especially in cement or concrete

tanks or earthen ponds in which the water depth is small.

vii) Excessive growth of aquatic macro-vegetation and phytoplankton and

depletion of dissolved oxygen particularly during nights and/or after several

continuous rainy days, causing asphyxiation of fish and supersaturation of

oxygen during hot sunny days causing gas embolism among fish.

viii) Inherent toxicity of certain algal blooms.

ix) Afflictions by ecto- and endoparasites; bacterial, fungal and viral infections

causing disease and mortality.

x) Abnormalities and ill health arising out of nutritional deficiencies.

To prevent the above difficulties and mortality of fish seeds in check, preparation

and management of nursery and rearing ponds is of utmost importance in achieving success

in fish seed production.

Nursery pond Management:

Nursery ponds are shallow and preferably seasonal ponds, which dry up in the

summer months. These ponds are rectangular, 0.02-0.04 ha in size and of less than 1 m

depth. Indian Major Carp (Catla, Catla catla; Rohu, Labeo rohita; and Mrigal, Cirrhinus

mrigala) spawns ( 3 days old) are nursed in this type of pond only for 12-15 days. During

this period 5-6 mm size spawn of around 0.0014 g are grown into 25-30 mm size fry of 0.5

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g. Nursery pond management is divided into two phases a) pre-stocking management and

b) post-stocking management.

Pre stocking management:

Eradication and controlling of aquatic weeds: This is done to ensure free living space

for the very small size spawns, to ensure enemy free environment as aquatic weeds harbour

many predatory insects and harmful organisms, to ensure less diurnal variations of

dissolved oxygen and to make periodic netting easier. There are several options like

manually clearing the small sized marginal and floating weeds, mechanically uprooting

particularly the rooted macrophytes and chemical control of the large bodied floating

macrophytes that are rooted underneath the pond sediment. But it is always best to

manually cleaning the only the marginal macrophytes of the nursery pond as during pond

preparation it is expected that it is dried up during the summer. Mechanical control of

aquatic weeds is usually practiced in big water bodies and employing mechanical means is

also costly. On the other hand, chemical control of aquatic weeds using herbicide or

weedicide is not preferable as it may render residual chemical effect in water might be toxic

to the spawn.

Eradication of predatory and weed fishes: Predatory and unwanted weed fishes either

directly predate upon the spawns of desired species or compete for living space, dissolved

oxygen and food. As nursery pond generally dried up during summer there may have some

mud dwelling predatory fishes (murrels and cat fishes) but no smaller variety of weed

fishes. If some water is still retained in the pond after summer it is best to repeatedly net

the water so as to get rid of at least 80% of the weed fishes. But for the mud dwellers fish

toxicants must be used of which plant derivatives are preferred over the chemical piscicides

(organophosphate compounds and synthetic pyretheroids) because they don‟t exert long

term residual toxicity. Several plant derivatives like tea seed cake, mohua oil cake (saponin

containing) and derris root powder (rotenone containing) are in use for eradicating

predatory and weed fishes. But mohua oil cake containing 4-6% saponin (maurin) is

Training Compendium

71

popularly used as a fish toxicant because of its dual effect first as a toxicant then

subsequently as manure upon decomposition. Usually it is powdered and broadcasted @

200-250 ppm (2000-2500 kg/ha per meter water depth) and water is vigorously agitated.

Within 4-6 hours all the fish are died and the dead fish are safe for human consumption.

The toxicity generally persists for 15-20 days during that time it is not advised to use the

water for domestic cattle.

Manuring: After seven days of mohua oil cake application raw cow dung @ 5000 kg/ha is

used to supply essential nutrients like carbon, nitrogen and phosphorus into the system for

development of planktonic biomass. It is to be noted here that if mohua oil cake is not used

(in case of dried pond) the dose for cow dung will be 10000kg/ha and it is applied after

filling the pond with water.

Liming: Liming is done to correct the pH of both soil and water to its alkaline range as

fish culture needs slightly alkaline pH, to destroy the pathogenic microbes and to enhance

mineralization of the organic matter in water as well as in sediment. After seven days of

manure application lime is applied @ 200 kg/ha. If the pond is a dried one then it needs

ploughing and in that case lime is applied in dry powder form after first ploughing

(parallel). During second ploughing (cross) lime is well mixed with the soil containing

some moisture which results in heating thereby destroying the harmful organism in the

mud. In case, lime is applied directly in water then the required amount is mixed with

water well in advance so as to cool down the slurry before application. It is then

broadcasted over the water surface and thoroughly mixed with water by netting.

Eradication of harmful aquatic insects: It is extremely necessary particularly in nursery

pond as the insects may act as predators, compete for dissolved oxygen, food and space.

This is done not more than 48 hours before releasing of the spawns because insects are of

flying and jumping habits and may migrate from nearby ponds. Also, they breeds

frequently with huge fecundity and repopulate the culture pond if the practice is done much

in advance. There again are several options like repeatedly netting the pond water. But

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total removal of insect is not possible by this manual method. Among the chemical options

there are several insecticides available but it is not at all judicious to apply in the aquatic

environment because of there long term persistency and residual side effects. Moreover,

chemical insecticides are not selective in destroying only the aquatic insects but they are

also very harmful for the valuable zooplanktons. Therefore, it is better to apply soap-oil

emulsion upon the water surface to block the respiratory mechanism of the insects to

destroy them. Any cheap detergent powder @ 18 kg/ha is mixed with hot water and the

solution is gently poured in a containing @ 56 kg /ha cheap oil with vigorous stirring. The

emulsion is formed and it is applied over the water surface along with the wind direction

from one side of the pond. The emulsion will create a film over the surface barricading the

insects frequenting the surface for respiration. All the insects will die out within a short

while; they are removed by netting so as to prevent decomposition of the dead insect within

the system. Netting out of the dead insects also breaks down the oil film into pieces and

they are ultimately deposited along the margins thereby not harming the spawns to be

released subsequently.

Stocking: Stocking of spawn on the nursery pond should be done with much caution.

The usual stocking rate for IMC is 4.5-5 million spawn /ha. This is usually done during

cool early morning of the day. Before releasing spawn the temperature of water in the

container carrying the spawn and the nursery pond should be adjusted dipping the container

upto its neck into the nursery pond. The physicochemical incompatibility of water is

adjusted by exchanging water between them gradually in small installments. After

adjustment of water quality the container carrying the spawn is slowly inclined so that the

spawns spontaneously come out from the container into the nursery ponds.

Post stocking management:

Post stocking management in the nursery pond involves feeding the spawn with

powdered supplementary feed prepared with rice bran and oil cake in equal proportion

initially @ four times the body weight and gradually increased upto eight times of the body

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weight. For ease of calculation, the estimated body weight of one million spawn is 140g

may be taken into consideration. Weekly netting with cloth hapa is done so as to release the

harmful gases in the sediments and to make the fish swim actively for increasing metabolic

activity. The pond must be free from ducks during the culture as they actively predate

upon the spawn. The culture continues for 12-15 days and the fry is harvested after the

culture in nursery pond is over.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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CULTURE OF INDIAN MAJOR CARPS AND EXOTIC CARPS

Dr. T. K. Ghosh

Department of Aquaculture

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

Introduction:

Carps form the mainstay of aquaculture practice in India contributing over 85% of

the total aquaculture production. The three Indian major carps , viz. catla ( Catla catla),

rohu ( Labeo rohita) and mrigal (Cirrhinus mrigala) contribute bulk of the production in

the country whereas, the three domesticated exotic carps such as silver carp (

Hypopthalmichthys molitrix), grass carp (Ctenopharyngodon idella) and common carp

(Cyprinus carpio) form the second important group.

Carp culture in India was restricted only to a homestead backyard pond activity in

West Bengal and Odisha until late 1950s, with seed from riverine sources as the only input

resulting low level of production. Though importance of fish culture as an economically

promising enterprise was gradually realized by then, non availability of quality fish seed

and lack of scientific culture know-how constrained the development of carp farming.

Seed rearing and grow-out culture are the two main components of carp culture

technology, which have undergone several modifications and refinements over the years to

evolve to the present day‟s package of farming practices. The technologies of seed rearing,

comprising rearing spawn to fry in nursery and further fry to fingerlings in rearing ponds,

have been accepted as economically viable activities at the farmer‟s level throughout the

country.

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Packages of Practices:

The packages of practices were developed for the seed production and grow-out

farming of carps are discussed here.

Seed production:

Nursery pond management: Seed of carps are delicate in nature and their growth and

survival largely depend on the environment in which they live. The biological

characteristics like the food preference and feeding habit of these carps are almost similar

during their initial life stages, thus requiring almost similar management at any particular

stage. The survival and growth of these seeds in rearing systems largely depend on the

presence or absence of aquatic weeds, aquatic insects and predatory and weed fishes, water

and soil quality, availability of natural feed, population density, supplementary feed,

rearing period, etc.

The nursery phase refers to the rearing of the three to 4-day old spawn in nursery ponds

for a period of 15 to 20 days for major carps and 20 to 25 days for medium carps till they

grow to fry stage. Generally, smaller seasonal earthen ponds of 0.02 to 0.1 ha size with

average water depth of 1.0 to 1.5 m is preferred for carp nursery. Drying of ponds during

summer helps in eradication of predatory and weed fishes and organic mineralization.

Perennial water-bodies are often infested with aquatic weeds and harbor predatory and

weed fishes. Thus, these perennial ponds when used as nurseries need a series of pre-

stocking management measures to provide a suitable growing environment for the seed.

Control of aquatic weeds:

The earthen ponds are often infested with marginal, floating, submerged and emergent

aquatic weeds. The presence of these weeds cause many problems: i) absorb available

nutrients, ii) prevent light penetration, iii) cause oxygen deficiency during night, iv) cause

higher diurnal pH fluctuation, v) harbor aquatic insects and predators, vi) reduce living

space for fish, vii) hinder free movement of fish, viii) cause problem in netting operation,

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ix) increasing siltation in the pond. Complete removal or control of these weeds thus is a

pre-requisite.

Soil correction:

The productivity of a fish pond depends on the physical, chemical and biological

properties of the pond soil. Pond bottom acts as the laboratory where process of

mineralization of the organic matter takes place and nutrients are released to the overlying

water column. Physical properties of soil like texture and water retentivity, and chemical

properties like pH, organic carbon, available nitrogen and available phosphorus are

important parameters which require considerable attention for effective pond management.

Slightly acidic to neutral soil with pH 6.5 to 7.0 is considered to be productive. Since low

soil pH is always associated with low productivity, pond bottom with such pH needs

correction, which is usually done through application of lime. Quick lime (CaO) is

preferred for soil treatment during pond preparation while calcite and dolomites are used

for the treatment and pH correction of pond water during culture operation.

Eradication of predatory and weed fishes:

Perennial water-bodies harbour a number of predatory animals likes fish, snakes,

tortoise, frogs, etc., which cause extensive damage to the seed population. Predatory and

weed fishes enter into the pond ecosystem through the incoming surface runoff during

monsoon. Most of these undesirable fishes normally breed in the pond prior to the onset of

carp spawning season and establish their population. These fishes not only feed on the carp

spawn, drastically reducing their population, but also compete with them for food, space

and oxygen, severely affecting their survival and growth. Therefore, removal of these fishes

from the nursery pond is a prime requirement to ensure higher seed survival and optimum

environment for their growth.

Pond fertilization:

The Indian major carps and exotic carps at their early stages are planktivorous, with

zooplankton as the preferred natural food. Sustained zooplankton population in a pond

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depends on a good phytoplankton population base, which is further ensured through

adequate availability of major nutrients like nitrogen, phosphorus and carbon, besides

certain micronutrients in water. The in-situ availability of these nutrients in pond sediment

and water is often at lower levels and need to be added from external sources for sustaining

good plankton growth. Such nutrients are supplied to the pond water through application of

organic and inorganic fertilizers.

Control of aquatic insects:

Pond ecosystem harbours number of aquatic insect species. These insects often find

their way from the adjacent ponds into the prepared nursery and increase their population

tremendously just after fertilization of the pond. They not only compete with the carp seed

for food, but also cause extensive damage, often killing them through devouring or pricking

and sucking the body fluid resulting in poor seed survival. The aquatic insects belonging to

orders Coleoptera, Hemiptera and Odonata are relatively more important. Among these, the

back-swimmers cause maximum loss to carp spawn by eating upon the spawn as soon as

they are released. These back-swimmers are capable of killing the carp fry even 10-13 mm

in size through piercing their sharp sucking beak into the body of fry and suck out the body

fluids.

The simple and effective method of eradication of aquatic insects had been through the

application of soap-oil emulsion, i.e. 18 kg /ha of cheap soap and 56 kg/ha of vegetable oil,

applied at one to two days before stocking of spawn. Application of such emulsion is more

effective during calm weather. Detergent powder (2-3 kg/ha) can be used effectively as

substitute of soap-cake. In smaller ponds, repeated netting with suitable mesh size just

before stocking of spawn can be an alternative method for insect control.

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Indian major carps:

1. Mrigal (Cirrhinus mrigala):

Morphology: Body elongated, cylindrical. Its depth is about equal to the length of the

head. Blunt snout and often pores are present. Broad mouth. Upper lip entire, horny, lower

lip indistinct, with single short pair of rostral burbels. Subterminal mouth with thin non-

fringed lips. Three rows of pharyngeal teeth present. Dorsal fin as high as body. Pectoral

fin is shorter than the headand caudal fin deeply forked. 40-45 scales are present on the

lateral line.

Colour: Golden eyes. Dorsal side of the body dark grey often with a coppery tinge and

ventral silvery white. Pectoral, pelvic and anal fins oranged tipped, while dorsal and caudal

fins are dusky.

Distribution: Widely distributed in northan India, Pakisthan, Bangladesh, Burma and

adjacent hilly areas. It has established in South India and forms a component of commercial

fisheries. Occurs in the principal rivers of India and is an inhabitant of rivers and tanks in

Bengal. Mrigal is a moderately fast growing freshwater major carp, its fishery is great

commercial importance. It is one of the most important carp and it has a good matket

demand and is renouned for its good taste.

Food and Feeding: The adult is a bottom feeder on decaying organic and vegetable debris;

however, its young feeds on zooplankton. Adult fish feed on algae, diatoms, higher plants

and detritus. Hatchlings of mrigal normally remain in the surface or sub-surface waters,

while fry and fingerling tend to move to deeper water. Adults are bottom dwellers. It is an

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illiophage in its feeding habit and stenophagous; detritus and decayed vegetation form its

principal food components, while phytoplankton and zooplankton comprise the rest.

Growth: The maximum size attained is 0.9 m, reported to have attain a size of 12.7 kg. Its

growth in the first year is about 30 cm (700 g). Matures in the second year. It breeds

naturally in rivers in rainy season; though artificial propagation by hypophysation is

possible.

Culture: Indian aquaculture is mainly carp based where three Indian major carps, viz.

catla, rohu and mrigal, are grown together under polyculture system or along with the three

exotic carps, viz. silver carp, grass carp and common carp, as the six species composite

carp culture systems. Among the six species, the three Indian major carps are

comparatively slow growing than their exotic counterparts. Thus, polyculture of three

Indian major carps usually yields lower production than the six species composite culture

system.

Carp culture is undertaken mostly in earthen ponds of varying dimensions. Judicious

selection of compatible fast growing species is of vital importance in maximizing fish

production. A combination of six species, viz. Catla (Catla catla), Silver carp

(Hypophthalmichthys molitrix), Rohu (Labeo rohita), Grass carp (Ctenopharyngodon

idella), Mrigal (Cirrhinus mrigala), and Common carp (Cyprinus carpio) fulfills the

species selection requirement and has proven to be ideal combination for freshwater carp

culture in Bangladesh. Of these, Catla and Silver carp are surface feeders, Rohu is a column

feeder, Grass carp is a macrovegetation feeder and Mrigal and Common carp are bottom

feeders. The six species combinations have been found to yield maximum production and

these species are the “back bone” of composite culture. Mrigal is eurythermal, appearing to

tolerate a minimum temperature of 14 ºC. In culture, the species normally attains 600-700 g

in the first year, depending on stocking density and management practices. Among the

three Indian major carps, mrigal normally grows more slowly than catla and rohu. The

rearing period is usually confined to a maximum of two years, as growth rate reduces

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thereafter. However, mrigal is reported to survive as long as 12 years in natural waters.

Mrigal is a highly fecund fish. Fecundity increases with age, and normally ranges from

100 000-150 000 eggs/kg body weight. The spawning season depends upon the onset and

duration of the south-west monsoon, which in India, Bangladesh and Pakistan extends from

May to September. Mrigal usually breeds at 24-31 ºC.

Mrigal is cultured mainly as a component of carp polyculture systems in the ponds of

India and Bangladesh, the major producing countries. Mrigal is normally cultured along

with the other two Indian major carps - catla (Catla catla) and rohu (Labeo rohita). It is

also cultured in composite carp culture systems that include the three Indian major carps as

well as two Chinese carps - silver carp (Hypophthalmichthys molitrix) and grass carp

(Ctenopharyngodon idella) - and common carp (Cyprinus carpio). Being a bottom feeder,

mrigal is usually stocked at 20-30 percent of the total species stocked in three-species

culture, while in six-species culture mrigal constitutes only about 15-20 percent.

Grow-out culture of mrigal in polyculture systems is confined to earthen ponds and

normal management practice includes predatory and weed fish control with chemicals or

plant derivatives; stocking of fingerlings at a combined density of 4,000-10, 000

fingerlings/ha; fertilization with organic manures like cattle dung or poultry droppings and

inorganic fertilizers; supplementary feeding with a mixture of rice bran/wheat bran and oil

cake; and fish health monitoring and environmental management. Production is normally 3-

5 tonnes/ha/yr, with mrigal contributing about 20-25 percent.

Mrigal also forms one of the important components in the sewage-fed carp culture

system practiced in an area totalling over 4000 ha in West Bengal, India. In this form of

culture, which includes multiple stocking and multiple harvesting of fish larger than 300 g,

primary treated sewage is provided to the fish ponds as the main input. Even without the

provision of supplementary feed, this system produces 2-3 tonnes/ha/yr. With

supplementary feeding, this can be increased to 4-5 tonnes/ha/yr.

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Harvesting techniques: The bottom dwelling habit of mrigal hinders its effective

harvesting by dragnet, the most common gear used in carp culture. Complete harvesting is

possible only through draining. These harvesting difficulties make mrigal the least

preferred species among the three Indian major carps for farmers. Cast nets are often used

for partial harvesting in small and backyard ponds.

Exotic carps:

1. Common carp ( Cyprinus carpio):

Morphology: Body compressed laterally, moderately elongate, covered with large cycloid

scales. Deep body and short head. Body height 1/4 body length. Triangular head with blunt

snout and thick nose plate. Two pairs of short barbells. Small horizontal mouth located

below snout. No teeth, no true spines in fins, 35-38 lateral line scales, 4-6 anal fin rays, 14-

17 pectoral rays, 8-9 pelvic fin rays, 21-27 gill rakers, and molariform pharyngeal teeth.

Colour: Olive green coloration above, golden on sides, yellowish below. Belly, pectorals

and pelvics- light yellow, ventral fin orange, caudal fin gray with orange shade. Fins often

reddish. Two genetic variations of common carp exist: the mirror carp with very few scales

and the leather carp with no scales. Domesticated forms of common carp (koi) exhibit a

variety of black, white, and gold scale patterns.

Distinguishing Characteristics: Common carp may be confused with goldfish (Carassius

auratus), carpsuckers (Carpiodes), and buffalo fishes (Ictiobus) of similar size. Common

carp can be distinguished from carpsuckers and buffalo fishes by the first ray of dorsal and

anal fins, which are modified into hard serrated bony structures. Common carp can be

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distinguished from other native minnows and the goldfish by two barbels present at each

corner of the mouth. Common carp can also be distinguished from other native minnows

by elongate fins with more than 11 soft rays.

Distribution: Common carp (Cyprinus carpio) is probably one of the few aquaculture

species that can be considered to have been domesticated. Presently cultured all over Asia,

in most parts of Europe including USSR, and on a small scale in some countries of Africa

and Latin America. It has also been introduced in North America and Australia. Common

carp is a fast growing freshwater exotic carp, its fishery is great commercial importance.

Food and Feeding: The adult is a bottom feeder on decaying organic and vegetable debris;

however, its young feed on phytoplankton, zooplankton, protozoan, small crustaceans and

insect larva. Adult fish feed on bottom detritus, composed of decayed plant matter and

benthic organisms.

Growth: Growth varies with geography. Highest in tropical and sub tropical conditions,

modest in temperate climates. The maximum size attained being 75 cm and 6.0 kg. It is a

fast growing and a fairly hardy fish. High growth rates, reaching 40-45 cm and 1.0-1.5 kg

in their first year. Matures in the second year. All its varieties breed freely in ponds without

hypophysation. Eggs are adhesive to submerged vegetation.

Culture: Carp culture is a highly economic and profitable enterprise. Among many fish

farming practices, the composite fish culture is one, which a common fish farmer can easily

adopt with comparatively less investment to have more production and income than the

traditional farming practice. The common practice of composite culture includes 6 species

of carps (3 indigenous and 3 exotic fishes) viz. Catla, Rohu, Mrigal, Silver carp, Grass carp

and Common carp. Generally, the species ratio is 30-40 % surface feeder; 15-20% column

feeder, 40-50% bottom feeder and 5-15% macro vegetation feeder depending upon the

depth and productivity status of the pond.

Common carp is a warm water species and does well in muddy, eutrophic (highly

productive, rich in mineral and organic nutrients) waters. The earliest form of fish culture

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was that of Common carp (Cyprinus carpio) a native of China. From there, this species has

been introduced into several countries of Asia, far East and Europe. From the 6th Century

A.D. the culture of common carp declined in China.

Common carp dwells in middle and lower reaches of rivers and shallow confined

waters. Best growth is obtained at water temperature of 23-30°C. The fish can survive cold

winter periods. Salinity up to about 5‰ is tolerated, optimal pH is 6.5-9.0; common carp

can survive low oxygen concentration (0.3-0.5 mg / l) as well as super saturation. Carp are

omnivorous, with a high tendency towards the consumption of benthic organisms, such as

water insects, larvae of insects, worms, molluscs, and zooplankton. Digging in the bottom

in search for food items results in turbid water. Zooplankton consumption is dominant in

fish ponds where the stocking density is high. Additionally, the carp consumes the stalks,

leaves and seeds of aquatic and terrestrial plants, decayed aquatic plants, etc.

Typical carp ponds in West Bengal are shallow, eutrophic with a muddy bottom and

dense aquatic vegetation at the dikes. Pond farming of common carp is based on natural

food with supplemental feeding of cereals. Daily growth can be 2 to 4% of body weight

(bw). Carps can reach 0.6 to 1.0 kg bw within one season in subtropical/tropical

polyculture. Growth in temperate climate is slower, the fish reach 1.5 kg bw after 3 rearing

seasons. Maturity period of Asian breeds is slightly shorter.

Peak spawning occurs from May through July in shallow waters. The sticky eggs

(100,000 to 500,000 in number) are laid on submersed aquatic plants and after contact with

water, they become adhesive and swell 3-4 times in volume, hatch in less than a week.

Hatched fry stick to substrate and live from yolk supplies. Common carp fry feed on

plankton. Juveniles and adults are found in deeper waters feeding predominantly on

aquatic plants, algae and small invertebrates near the bottom. Three days after hatching the

posterior part of the swim bladder develops, the larvae start to swim and consume external

food of 150-180 μm size.

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The bottom feeding habits (rooting) of this fish prove to be quite destructive. When

overabundant, carp cause an increase in water turbidity and a decrease in aquatic plants and

invertebrates. Evidence has also proven that the common carp prey on the eggs of other

fishes and their foraging activities can destroy spawning beds of more desirable species.

Therefore, common carp are responsible for the decline of some native fish species.

Harvesting techniques: The bottom dwelling habit of common carp hinders its effective

harvesting by dragnet, the most common gear used in carp culture. Complete harvesting is

possible only through draining. Cast nets are often used for partial harvesting in small and

backyard ponds.

2. Silver carp (Hypophthalmichthys molitrix):

Morphology: The silver carp is a deep-bodied fish that is laterally compressed. They are a

very silvery in color when young and when they get older they fade from a greenish color

on the back to silver on the belly. They have very tiny scales on their body but the head

and the opercles are scaleless. They have a large mouth without any teeth in the jaw, but

they have pharyngeal teeth. Its eyes are situated far forward on the midline of the body and

are slightly turned down. The silver carp is fairly uniform in color whereas the bighead has

irregular dark blotches on its back and sides. The silver carp has a sharply keeled belly

from the anal fin to the throat, whereas the bighead carp has a keeled belly from

approximately its pelvic fins to the anal fin.

Colour: The body thick up and down but somewhat flat side to side and they are usually

have olive-green backs and silver sides, but sometimes have a bronze to red tinge. Silvery

in colour, body covered with small silvery scales.

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Distribution: Native to Asia but spread worldwide as a food fish and introduced into the

wild accidentally. The silver carp (Hypophthalmichthys molitrix) is a species of freshwater

cyprinid fish, a variety of Asian carp native to north and northeast Asia. It is cultivated

in China. It has been introduced to, or spread into via connected waterways, at least 88

countries around the world. They are usually farmed in polyculture with other Asian carps,

or sometimes Indian carps or other species.

Food and Feeding: The silver carp is a filter feeder, and possesses a remarkably

specialized apparatus capable of filtering particles as small as 4 micrometers (µm). The gill

rakers are fused into a sponge-like filter, and an epibranchial organ secretes mucus which

assists in trapping small particles. Silver carp, like all Hypophthalmichthys species, have no

stomachs; they are thought to feed more or less constantly, largely on phytoplankton; they

also consume zooplankton and detritus.

Because they feed on plankton, they are sometimes successfully used for controlling water

quality, especially in the control of noxious blue green algae (cyanobacteria). Certain

species of blue-green algae, notably the often toxic Microcystis, can pass through the gut of

silver carp unharmed, and pick up nutrients while in the gut. Thus, in some cases, blue-

green algae blooms have been exacerbated by silver carp.

Growth: Growth varies with geography. The maximum size attained is 60 cm. It is a fast

growing and a fairly hardy fish. High growth rates, reaching 1.5 kg in their first year. Silver

carp can grow to over three feet in length and to nearly 100 pounds. Silver Carp spawn in

flowing water. They spawn in 18 to 20 C degree water by running upstream and groups of

15 to 20 fish release eggs and sperm into the water, where they must float freely until

hatching. Matures in the second year. It breeds naturally in rivers in rainy season; though

artificial propagation by hypophysation is possible.

Culture: Silver carp is an important candidate species of composite culture which includes

6 species of carps (3 indigenous and 3 exotic fishes) viz. Catla, Rohu, Mrigal, Silver carp,

Grass carp and Common carp. Generally, the species ratio is 30-40 % surface feeder; 15-

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20% column feeder, 40-50% bottom feeder and 5-15% macro vegetation feeder depending

upon the depth and productivity status of the pond.

Silver carp have become notorious for being easily frightened, which causes them to leap

high into the air. The fish can jump up to 2.5–3 m (8–10 feet) into the air. Silver carp can

grow to 45 kg (100 lb) in mass. This behavior has sometimes also been attributed to the

very similar bighead carp, but this is uncommon.

The major pathway for introduction of silver carp in the United States was importation for

biological control of plankton in sewage lagoons and culture ponds. Silver carp are difficult

to handle and transport because of their propensity to jump and avoid being taken by

seines. These negative attributes have resulted in little silver carp culture in the United

States since 1985. Silver carp are not being cultured commercially currently. Silver carp

naturally occur in a variety of freshwater habitats including large rivers and warm water

ponds, lakes, and backwaters that receive flooding or are otherwise connected to large

rivers. Silver carp occupy the upper and middle layers of the water column. Silver carp are

quite tolerant of broad water temperatures: from 4 °C to 40 °C. Silver carp are known to

feed at water temperatures of 10 to 19 °C; in the Missouri River, silver carp sometimes had

full guts at temperatures lower than 4 °C. Silver carp can live in slightly brackish waters.

Silver carp regularly jump out of the water when disturbed.

The reproductive potential of silver carp is high and increases with body size. Estimates

range from 145,000-5,400,000 eggs for fish 3.18-12.1 kg. Silver carp mature anywhere

from 3-8 years and male silver carp usually mature 1 year earlier than females.

The ability of silver carp to effectively filter particles and reliance on phytoplankton for

much of its diet has lead to the use of silver carp as a biological control agent for

phytoplankton. Silver carp are primarily phytoplanktivores, but are highly opportunistic,

eating phytoplankton, zooplankton, bacteria and detritus. Silver carp have been studied as

a potential tool for controlling excess nutrients in wastewater ponds, with mixed results.

Silver carp have been used in some states for removal of excessive algae from wastewater.

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Adverse effects of established populations of silver carp on endangered and threatened

fishes and mussels would vary. Adverse effects to fishes would most likely come about

through direct competition for food resources, particularly phytoplankton and, to a lesser

extent, zooplankton, in the water column during the larval stage. Potential for direct

predation and injury of drifting fertilized eggs and larvae of native fishes exist. In some

habitats, silver carp can develop extremely large populations that could bring about decline

of native fishes. Large populations of silver carp may alter the native fish community

structure, ultimately resulting in decline of native mussels since many rely on native host

fishes for reproduction.

Fishes most likely to be affected are those species whose diet is predominantly plankton,

including catla and they may be at risk because of the drastic reduction of plankton by large

populations of silver carp or hybrids.

3. Grass carp (Ctenopharyngodon idella):

Morphology: Body elongated and cylindrical, round abdomen, compressed at the rear;

standard length is 3.6-4.3 times of body height and 3.8-4.4 times of head length; length of

caudal peduncle is larger than the width; head medium; terminal mouth and arch-shaped;

upper jaw extends slightly over lower jaw, its rear can reach below eye; snout width is 1.8

times of the length, snout length is about the nasal distance; no palpus; gill rakes short and

sparse (15-19); two rows of pharyngeal teeth on each side, laterally compressed, formula

2.5-4.2, inner row stronger, grooves on the lateral surface; scales large and cycloid; extreme

39-46 scales in lateral line, lateral line extends to caudal peduncle. Anus close to anal fin.

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Dorsal fin ray: 3,7; pectoral fin ray: 1,16; ventral fin ray: 1,8; anal fin ray: 3,8; caudal fin

with around 24 rays.

Colour: Greenish yellow laterally, dorsal portion dark brown; greyish white in abdomen.

Distribution: Grass carp is a native Chinese freshwater fish with a broad distribution from

the catchment area of the Pearl River in southern China. The culture of grass carp remained

relatively small in scale due to the dependence on the natural supply of seed. Today, China

is by far the major producer (3 419 593 tonnes in 2002, 95.7 percent of the global total) of

grass carp. In 2006, many countries reported cultured production of grass carp to FAO but

only some of them (Bangladesh, China, Taiwan Province of China, Islamic Republic of

Iran, the Lao People's Democratic Republic, Myanmar and Russian Federation) reported a

production greater than 1 000 tonnes. The fish has been introduced to more than 40 other

countries; sometimes it is referred to as the white amur.

Food and Feeding: It inhabits lakes, rivers and reservoirs. It is a basically herbivorous fish

that naturally feeds on certain aquatic weeds. However, the fry/larvae feed on zooplankton.

Under culture conditions, grass carp can well accept artificial feed such as the by-products

from grain processing, vegetable oil extraction meals, and pelleted feeds, in addition to

aquatic weeds and terrestrial grasses. Grass carp normally dwell in mid-lower layer of the

water column. Comparatively, it prefers clear water and can move swiftly. It is a semi-

migratory fish; the mature broodstock migrate to the upper reaches of major rivers to

propagate.

Growth: Flowing water and changes in water level are essential environmental stimuli for

natural spawning. The fish can reach sexual maturity under culture conditions, but cannot

spawn naturally. Hormone injection and environmental stimuli, such as flowing water are

necessary for induced spawning in tanks. In India, dry or wet stripping methods are used

for the seed production of grass carp. Pituitary extract or synthetic agents such as ovaprim

are used for induction .Gras carp grow rapidly and reach a maximum weight of 35 kg in the

wild.

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Culture: Monoculture of grass carp is practiced in the nursery stage, with a stocking

density normally ranging between 1.2-1.5 million/ha, depending on the length of rearing

and targeted size. The nursery operation usually takes 2-3 weeks in China. Organic

fertilization is carried out at frequencies and rates sufficient to maintain high pond fertility

and therefore a good supply of natural food organisms (especially zooplankton) for the fish.

The quantity ranges from 1 500-3 000 kg/ha once every 4-5 days for animal manure or

green manure, depending on existing water fertility. Normal survival rates in nursery ponds

are 70-80 percent, although it may reach over 90 percent under good management.

The fish usually reach the size of about 30 mm in length after 2-3 weeks of rearing. These

are called summer-fingerlings in China and are ready for the fingerling rearing stage.

It is difficult to culture grass carp from the yearling size (13-15 cm) to marketable size

(>1 500 g) within one year in most parts of China; it is therefore common practice to rear

yearlings to 2 year old fingerlings for grow-out stocking. The stocking density is much

reduced, compared to the rearing of yearlings. The feeding regime is similar but the rate is

much higher. By the end of this period, the fish have usually reached about 250 g. This

practice is not necessary in tropical and subtropical areas, where yearlings of grass carp can

reach marketable size within one year, due to high temperatures.

The grow-out of grass carp is mainly conducted in earthen ponds and cages in Vietnam.

Polyculture with other species (e.g. silver carp, common carp, rohu and mrigal etc.) is

common. Grass carp may be stocked as either major or secondary species. Grass carp

usually account for 60 percent of the total stocking density of 1.5-3 fish/m² (dependent on

the level of intensity) in ponds and the fingerling size is 5-6 cm (mountainous areas) and

12-15 cm (lowlands). The stocking rate in cage culture is 20-30 fish/m³ but much larger

fingerlings are used (normally 50-100 g). Grass carp are usually fed with terrestrial grasses,

cassava leaves, banana stems and maize leaves in grow-out culture. Grass carp production

usually accounts for 60 percent of total production (7-10 tonnes/ha) in ponds.

In India, grass carp are cultured as an important species in pond-based composite

systems consisting mainly of Indian major carps and Chinese carps. The grass carp

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stocking density depends mainly on the availability of aquatic weeds and terrestrial grasses

but is usually 5-20 percent of the total. Aquatic weeds (Hydrilla, Vallisneria, Wolffia) and

terrestrial grasses such as Napier grass and other hybrid grasses are the major feeds in grass

carp farming. Normally, grass carp reach 0.5-1.5 kg in 8-10 months. Grass carp can be

reared with commercial feeds or natural food, such as aquatic weeds and grasses. They

prefer relatively low fertility. Production is mainly limited by water quality. The

commercial feeds used for grass carp are relatively low in protein (28-30 percent) and their

raw materials include soybean cake/dregs, rapeseed cake and wheat bran etc. Aquatic

weeds can be collected from natural water bodies. Terrestrial grasses can be grown on the

pond dyke with organic manure.

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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TILAPIA FARMING IN INDIA

Dr. B K Chand

Directorate of Research, Extension & Farms

West Bengal University of Animal & Fishery Sciences

68 K B Sarani, Kolkata, India 700 037

E mail: kinkarbimal@yahoo.co.in

Introduction:

Tilapia farming first gained popularity as an easily farmed fish that could supply cheap but

high-quality animal protein in developing countries. Tilapia species is native to Africa and

Middle East, and has emerged as one of the most favoured candidate species for culture all

over the world. The uncontrolled breeding of tilapia in ponds, which led to excessive

recruitment, stunting and a low percentage of marketable-sized fish, dampened the initial

enthusiasm for tilapia as a food fish. However, the development of hormonal sex-reversal

techniques in the 1970s, followed with research on nutrition and culture systems, along

with market development and processing advances, led to rapid expansion of the industry

since the mid-1980s. From 1980 onwards, tilapia aquaculture is growing at a compounded

rate of about 8% annually. The farming of tilapias, especially of Nile tilapia (Oreochromis

niloticus) in its crudest form is believed to have originated more than 4000 years ago from

Egypt. The first recorded scientifically oriented culture of tilapia was conducted in Kenya

in 1924 and soon spread to many parts of the world. In India Tilapia was introduced in

1952 with stocking of reservoirs in South India (Desai, 2006). The last three decades have

seen significant developments in farming of tilapias worldwide. They are being farmed in

about 85 countries worldwide (FAO, 2008) and about 98% of tilapia produced in these

countries are grown outside their original habitats (Shelton, 2002). Global tilapia

aquaculture production in 2009 was 3.08 million mt, with China, Indonesia, Egypt and the

Philippines being the top producers.

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Species Suitable for Aquaculture:

Tilapia belongs to the family Cichlidae under order Perciformes. The tilapias have recently

been classified into three genera, based on parental incubation of eggs. The species of the

genera Sarotherodon and Oreochromis are mouth brooders, while Tilapia incubates eggs in

a lake or pond bottom built-in "nest”. There are about 70 species of tilapias, of which nine

species are used in aquaculture worldwide (FAO 2008). Important commercial species

include: the Mozambique tilapia (Oreochromis mossambicus), blue tilapia (O. aureus), Nile

tilapia (O. niloticus), Zanzibar tilapia (O. hornorum), and the red belly tilapia (O. zilli).

Though several species of tilapia are cultured commercially Nile tilapia is the predominant

cultured species worldwide.

Genetically Improved Farmed Tilapia (GIFT):

The genetically improved farmed tilapia (GIFT) strain of Nile tilapia, Oreochromis

niloticus, has been developed by the World Fish Center (formerly known as the

International Center for Living Aquatic Resources Management). After more than 10

generations of selection, the fish show fast growth, high survival rates, high fillet weights,

good flesh quality, disease resistance and good adaptation to various farming systems. To

date, the GIFT strain has been formally disseminated to 14 national government agencies,

and it is being widely cultured in many Asian and Latin American countries. In the

Philippines, GIFT and GIFT-derived strains account for about 75% of total tilapia

production.

Habitat & Biology:

Nile tilapia is a tropical species that prefers to live in shallow water. It is an omnivorous

grazer that feeds on phytoplankton, periphyton, aquatic plants, small invertebrates, benthic

fauna, detritus and bacterial films associated with detritus. It has non-cannibalistic habit. It

has capacity to withstand handling and transport stress. Sexual maturity in ponds is reached

at an age of 5-6 months. Spawning begins when the water temperature reaches 24°C. The

female incubates the eggs in her mouth and broods the fry after hatching until the yolk sac

is absorbed. Fecundity is proportional to the body weight of the female. A 100 g female

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will produce about 100 eggs per spawn, while a female weighing 600-1000 g can produce

1000 to 1500 eggs. Nile tilapia can live longer than 10 years and reach a weight exceeding

5 kg.

Technological Advancements in Hatchery & Farming Practices:

In populations of tilapia, males grow faster and are more uniform in size than females. For

this reason, the farming of monosex populations of tilapias which is achieved either by

manual sexing, direct hormonal sex reversal, hybridization or genetic manipulation, has

been reported as solutions to the problem of early sexual maturation and unwanted

reproduction. Four technologies / practices have contributed most to the advancement of

Tilapia aquaculture are:

Stocking good species such as Oreochromis niloticus instead of Oreochromis

mossambicus.

Hand sexing of juveniles: There are clear differences between the sexes in tilapia

species, particularly in the form of the urinogenital opening, fin morphology and adult

colouration. Skilled hatchery workers can achieve over 95 % male populations on 5-7

cm fish.

Hybridization: O. hornorum is the only known species which consistently produces all

male fry when crossed with O. niloticus or O. mossambicus. The main problem is the

maintenance of the pure lines.

Hormonal sex reversal: Fry can be collected at the yolk sac or first feeding stages, no

later than one week after released from the female, and fed with feed containing the sex

reversal hormone like 17-Alpha Methyl Testosterone.

Types of Farming:

Tilapia can be cultured in cage/ pen/ pond in freshwater as well in brackishwater area.

Tilapia farming ranges from a rural subsistence (extensive, low input practices, non-

commercial and for household consumption) to a large-scale (capital intensive, commercial

purpose and market driven) level, depending on the intensity of management employed.

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Cage Culture: Cage culture of tilapia avoids problems with over breeding because eggs

fall through the cage meshes. The other main advantage is that the farmer does not

necessarily need to own the water body where the cages are placed. The cages can be made

of netting or are sometimes made from bamboo or other locally available materials. The

fish derive most of their nutrition from the surrounding water; however they may also be

fed supplementary feeds. Typical stocking rates at harvest are 10 kg/m3 maximum.

Intensive cage culture with stocking rates of around 25 kg/m3 is also getting popular.

Average production levels are variable in different systems and countries. Under intensified

cage culture production levels of 100-305 kg/m3 are reported (Alceste and Jory, 2002).

Pond Culture: The main advantage of ponds is that fish can be grown very cheaply

through fertilization. Many different types of ponds are used for tilapia culture. The most

widespread, but most unproductive are low input ponds with uncontrolled breeding and

irregular harvesting; yields are typically 500-2000 kg/ha/yr of uneven sized fish. If

monosex fish are stocked and regular manuring and supplementary feeding is practiced

yields can be up to 8000 kg/ha/yr of even sized fish. Polyculture of tilapia with other native

fishes in freshwater ponds is also widely integrated with agriculture and animal farming.

Intensive tank culture: Intensive tank culture avoids problems with overbreeding because

there is no space for males to set up territories. It requires a constant supply of water, either

gravity fed or pumped. Usual maximum stocking rates in tanks where the water is changed

every 1-2 hours would be around at 25-50 kg/m3.

Culture Procedure:

Prior to stocking of seed the pond is thoroughly drained, cleared of obstructions, weed and

wild fishes that may be present. The pond bottom is allowed to dry up until it cracks before

refilling the pond with fresh clean water. Lime can be applied @ 200-500 kg/ha depending

on the pH level of soil. Organic fertilizer such as dried chicken manure, cattle dung etc. is

to be applied @ 500 to 1000 kg/ha. on the pond bottom with a water depth of 20-40 cm.

Inorganic fertilizer like Super phosphate and Urea can be applied @ 50-200 kg/ha

(combined) when the pond water level is 60 cm. Vigorous and disease-free seeds weighing

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5-10 gm each are suitable for stocking. Seeds may be procured from reliable source or from

own hatchery tanks. The larger the seed, the faster the growth and earlier the harvest. Only

properly acclimated and conditioned seed should be stocked. When stoked at higher

density, supplementary feeding is very important. Good quality floating pellet feed is ideal.

Protein requirements in supplementary feed are: 35-45% for below 1g fish size, 30-40% for

1-5g size, 25-30% for 5-25g size and 20-25% for above 25g size fish. Feeding rate also

varies depending on the fish size (up to 20g size: 8-10%, 20-50g size: 4-7% & above 50g

size: 2-3%).

Pond care and maintenance:

Daily care and maintenance of the tilapia ponds are minimal. The following maintenance

procedures are to be followed.

Maintain pond water depth of 100-120 cm. Fish need space for growth. Production of

fish food organisms is also enhanced if water volume is sufficient.

Apply fertilizer regularly. It is essential to maintain the production of natural food

organisms.

Prevent entry of predators. Heavy loss of seeds may result in ponds affected by

predators like carnivorous fish, water snake etc. Proper pond preparation includes

elimination of such pests. Predators may enter through water supply. This can be

prevented by installing nylon or metal screen in the water inlet.

Elimination of aquatic weeds are necessary. Aquatic weed compete with phytoplankton

for nutrients derived from fertilizers. Some forms of aquatic weeds cover the water

surface and limit plankton growth. A weedy pond also makes fish harvesting difficult.

Weeds can be avoided by stocking weed-eating fishes such as grass carp.

Avoid contamination of pond water with pesticides and other pollutants.

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History of Tilapia Introduction & Culture in India:

In India, tilapia (Oreochromis mossambicus) was introduced in 1952, with a view to filling

up unoccupied niches, such as ponds and reservoirs. The species spread all across the

country within a few years due to its prolific breeding and adaptability to wide range of

environmental condition. Overpopulation of the species affected the fisheries of several

reservoirs and lakes in India. Introduction of O. mossambicus in Jaisamand lake of

Rajasthan not only resulted in reduction of average weight of major carps, but also posed

threat to species like mahseers (Tor tor and T. putitora), which are on the verge of

extinction. The Fisheries Research Committee of India had imposed ban on tilapia

propagation in 1959. The Nile tilapia was introduced to India during late 1970s. In 2005,

River Yamuna harboured only negligible quantity of Nile tilapia, but in two years‟ time, its

proportion has increased to about 3.5% of total fish species in the river. Presently in the

Ganges River system, proportion of tilapia is about 7% of the total fish species. However,

tilapia holds vast promise to become an important species for aquaculture in India,

considering the demand for more fish. M/s Vorion Chemicals, Chennai had successfully

cultured and marketed some varieties of tilapia, and reported neither escapes to natural

water bodies nor any ecological threats. There are many unpublished data about the

availability of tilapia in reservoirs of Tamil Nadu and some other states of India. In the

Kolkata Wetlands, some farmers are producing mono sex tilapia on commercial scale in

waste water. Studies carried out at CIFA for a period of three years during 1998 to 2000

with GIFT tilapia had demonstrated production levels of 5-6 mt per crop of 4-6 months

duration. Further, the study also showed the possibility of tilapia farming under polyculture

with the three Indian major carps and showed higher growth over rohu and mrigal at similar

stocking levels. Monosex population (all male) also could be produced with provision of

17α Methyl testosterone treated feed for four weeks. Only four fish farmer groups, M/s

Aresen Bio Tech, A.P, Vijaywada, M/s Ananda Aqua Exports (P) Ltd., Bhimavaram, A.P,

M/s Indepesca Pvt. Ltd., Mumbai M/s CP Aqua (India) Pvt. Ltd., Chennai, and M/s Rajiv

Gandhi Centre for Aquaculture (RGCA), the R & D arm of the Marine Products Export

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Development Authority (MPEDA) are already permitted by Government of India for the

seed production and farming of tilapia (Mono sex and mono culture of Nile/GIFT/golden

tilapia) in accordance with the guidelines for the hatchery operation and farming of tilapia,

developed by the Sub-Committee under the National Committee on Introduction of Exotic

Aquatic Species into Indian Waters.

Growth Potential in India:

As the demand for fish is increasing, diversification of species in aquaculture by including

more species for increasing production levels has become necessary. Introduction of tilapia

in our culture systems is advantageous because it represents lower level in food chain, and

thus its culture will be economical and eco-friendly. Mono sex culture of tilapia is

advantageous because of faster growth and larger and more uniform size of males. The

development of Genetically Improved Tilapia (GIFT) technology is based on traditional

selective breeding and is meant to improve commercially important traits of tropical farmed

fish which is a major milestone in the history of tilapia aquaculture. Through combined

selection technology, the GIFT program achieved 12-17% average genetic gain per

generation over five generations and cumulative increase in growth rate of 85% in O.

niloticus (Eknath and Acosta, 1998). Other varieties like „red tilapia‟ also hold promise.

There is high potential of export of tilapia to US, Europe and Japan.

Government Guidelines for Tilapia Culture in India:

Commercial Intensive Farming of Tilapia is in nascent stage in India. The Ministry of

Agriculture (MoA), Govt. of India is in the process of constituting a Steering Committee at

National level to oversee and monitor the tilapia seed and grow-out production. This

Committee will empower respective State Fisheries Departments for monitoring,

controlling and surveillance (MCS) of Hatchery/Farming (Nursery as well as Grow-out)

facility. The draft guidelines are as below:

(Source: dahd.nic.in/dahd/WriteReadData/Tilapia_policy_guidelines_Final.pdf).

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Registration: Farmers who intend to take up Tilapia culture shall apply to the State

Fisheries Department in the prescribed Proforma for permission.

Location: Farms may be located in areas which are not prone for floods or in a buffer zone

around a declared sanctuary or bio-reserve or other vulnerable areas in order to avoid

escape to the open water bodies.

Type and culture Intensity: Farming of only monosex male/sterile (through either

hormonal manipulation or cross breeding) is permitted.

Area of Culture systems: Each Farm should not be less than 1.0 Acre water spread area.

Size of each pond should not be more than 10.0 Acres.

Species: Species recommended is Nile Tilapia or improved strains/hybrids of Tilapia

Size of the seed to be stocked: Grow-out ponds should be stocked with sex reversed tilapia

(SRT) seed of more than 10 g. 30 Days old sexually reversed tilapia (SRT) to be reared to

10 g size raised in on-farm nurseries or in registered seed farms.

Stocking density: Maximum no of 5 nos/m2

Bio-security: The approval for farming of tilapia shall be accorded only to those

ponds/farms which could maintain bio-security of the farm to ensure no escape of the

biological material from the farm to the water source or to any other source even in

situations like flooding. Outlet water from culture ponds must be screened and treated

before released into drains/canals/rivers during culture practice or subsequent to harvesting

in order to prevent escape of eggs into natural water bodies. Provision of Bird scaring

device/fencing is mandatory. Bund height should be high enough to avoid fish escape and

sluice gates must be provided with appropriate mesh size to prevent escape of fish/eggs/fry.

Intensive tilapia culture: Farms intending to undertake recirculatory farming practice

should register with state fisheries departments with a stocking density of not more than

150 nos/m3 with provision of floating feeds. Biosecurity measures followed in this case

must conform to the standards specified for Grow-out farms.

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Technical Suggestions:

Fertilization: Fertilization in pond culture using organic manures can be done depending

on the nutrient status of the soil as and when required.

Types of feeds: Formulated floating pellet feed/farm made pellet feed with minimum

protein content of 20%

Feed storage: Proper feed storage facility should be provided at the farm site with proper

ventilation and management of humidity. The feed should be stacked on raised wooden

platforms without touching the walls to avoid mold. The feed should be used within three

months from the date of production.

Harvesting: Feeding should be suspended one/two days prior to harvest. Harvesting may

be done using drag nets or any other quick harvesting methods.

Post-Harvest and Transport: Harvested fish should be immediately iced and transported

for domestic markets/processing plants. Adequate infrastructure facilities for processing of

tilapia in value added items should be encouraged.

References:

dahd.nic.in/dahd/WriteReadData/Tilapia_policy_guidelines_Final.pdf

en.wikipedia.org/wiki/Aquaculture_of_tilapia

www.aquaculture.ca/files/species-tilapia.php

www.echocommunity.org/resource/collection/.../Fish_Farming.pdf

www.mixph.com/.../tilapia-hatchery-management-fingerling-product...

www.neda.gov.ph/.../Tilapia%20Productiopn%20in%20Fish%20Cag...

www.spc.int/DigitalLibrary/Doc/FAME/.../Nandlal_04_Tilapia2.pdf

www.worldfishcenter.org/resource_centre/WF_2462.pdf

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

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SEWAGE FED FISH CULTURE PRACTICES IN EAST KOLKATA WETLAND

S. K. Dubey & R. K. Trivedi

Department of Aquatic Environment Management

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

1. Introduction

The East Kolkata sewage fisheries are the largest single wastewater use system involving

aquaculture in the world. In 1945, the area of sewage-fed fish ponds was about 4628 ha, in

a wetlands area of about 8000 ha, but the fish pond area had been reduced to about 3000 ha

by 1987 due to urban reclamation and conversion of fish ponds to rice paddies. Ownership

of the farms is with either Fishermen Cooperative societies, single owners or with West

Bengal State Fisheries Department. The farms under ownership of the Dept. are often

leased to Societies or Private Parties. Many more, in Kolkata city, depend on the fish and

vegetables produced; 13,000 tonnes of fishes are produced annually in ponds managed for

waste water aquaculture and 150 tonnes vegetables per day are harvested from small-scale

horticultural plots irrigated with wastewater. At present there are 254 wastewater-fed

fisheries occupying an area of about 3,800 ha, the largest wastewater-fed system in the

world, treating the city sewage and producing an average yield of 4 tonnes/ha of carps and

tilapia. The fish farms consist of units of various sizes from large holdings locally called

“bheri” and relatively smaller ones called “jheels” due to their trench-like elongated shapes.

The sewage-fed ponds are generally shallow and vary from 4ft to 6ft cm in depth. But all

these fish farms generally have similar types of produce, farming practice and distribution

system.

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2. Species cultured

Although both Indian and exotic carps are grown, farmers have specific preference for the

Indian carps, namely catla (Catla catla), rohu (Labeo rohita), mrigal (Cirrhinus mrigala)

and bata (Labeo bata) with bulk of the stocking consisting of mrigal. Exotic fish like silver

carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodon idella), common carp

(Cyprinus carpio) and Japani Punti (Puntius Javanicus) are stocked as a small percentage.

However, the popularity of tilapias (Oreochromis niloticus and O. mossambicus) is

increasing and they constitute 5-30% of the species stocked with different farms. There is

also a tendency for some farmers to stock Pangasius (Pangasianodon hypophthalmus) to

control mollusc populations and some are attempting to culture high value species like

giant freshwater prawn, Macrobrachium rosenbergii. Apart from these cultured varieties

(except Tilapia), some other varieties including forage fishes are also available occasionally

in the bheris like murrls (Channa striatus, Channa punctatus, Channa gachua), air

breathing catfishes (Heteropneustes fossillis, Clarias batrachus), and Fouli (Notopterus

notopterus) etc.

2.1 The average marketable sizes of fishes (in gram)

I. Indian Major Carp

Rohu 200-500

Catla 225-750

Mrigal 100 - 400

II. Indian Minor Carp

Bata 100 -200

III. Exotic Variety

Silver carp 200 - 400

Common carp 250-500

Grass carp 500-1000

IV. Tilapia

Mosambica 50 – 100

Nilotica 100 -250

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3. Sewage water Intake &Treatment

Water received in Sewage fed farms from the Kolkata Municipal Corporation Sewage

canal. The bulk of water coming in is channeled via canals to long distances and the inlet is

protected with a bamboo frame work which prevents entry of plastic or large matter in to

the canal and pond. In the ponds as well as in the canals aquatic vegetation is used as the

means of water treatment. Floating aquatic vegetation such as Lemna (duck weed), Wolfia,

Spirodella, Azolla etc are present in these canals leading to the ponds or bheries. This

vegetation reduces the organic load present in water and since the water moves very slowly

through the canals for long distances sedimentation occurs. The combined action of the

aquatic vegetation by removing the organic load and sedimentation will make water more

clear and applicable for fish culture. The entire canal, ponds and even the bheries is lined

by Eichornia crassipes which performs an array of functions such as heavy metal removal,

reducing organic load etc. Duck weeds are also capable of heavy metal removal. Colacasia

is planted all over the embankments, canal sides and it performs the same functions.

4. The Culture System

The culture system is multiple socking and multiple harvesting culture system. Fishes are

caught every day morning and fingerlings are stocked twice or thrice in a month i.e. every

10 or 15 days. Stocking is done very heavily to sustain daily harvesting. The culture system

is a zero feed and zero fertilizer system. The fishes are fully dependant on natural food

available from the nutrient rich treated sewage water. Hence in such a culture system the

only cost incurred is on fingerlings, craft & gear and dyke maintenance. The inlets and

outlets of every bheri, pond and canal is protected by bamboo sluice to prevent the entry of

other fishes from outside and escape of the stocked fishes.

4.1 Calendar of Activities

The wastewater-fed fishpond system follows a systematic calendar of activities involving

five major phases: pond preparation; primary fertilization; fish stocking; secondary

fertilization; and fish harvesting. Each phase comprises one or more activities. Pond

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preparation is carried out during the winter months of the year and involves: complete

draining of the pond; sun drying of the pond bottom; and dike repairing activities. In the

middle of February primary fertilization takes place when wastewater is introduced into the

pond and is allowed to undergo natural purification; before any fish are stocked, the pond is

stirred intensely to reduce anaerobic conditions in the sediments and promote the

development of benthic organisms for fish feed.

From the middle of March, fish stocking takes place. To ascertain the quality of water for

fish growth, the farmers have introduced a process of stocking test fish in which a small

number of fish are stocked as probe species to test water quality. Five major phases, each

involving one or more activities, characterize the Calcutta sewage-fed aqua cultural system.

Phase Activity

1. Pond preparation 1. Pond draining

2. Sun drying

3. Desilting silt traps

4. Tilling

5. Repairing dikes

2. Primary fertilization 1. Filling with sewage

2. Facultative stabilization

3. Stirring

3. Fish stocking 1. Test fish

2. Fish stocking proper

4. Secondary fertilization 1. Filling with sewage

5. Fish harvest 1. Net selection

2. Team management

3. Haul disposal

After obtaining satisfactory water quality, fish stocking properly takes place. In general,

fish are stocked four times. The size of fish stocked varies in the first and second stockings,

being 50-60 fish/kg (16.7-20.0 g) and 10,000-40,000 fish/kg (0.025-0.10 g), respectively.

Silver carp are stocked in July and common carp in December, each at between 400-600

fish/kg (1.7-2.5 g). Secondary fertilization consists of periodic introduction of wastewater

into the ponds throughout the growth cycle. However, the wastewater inflow may be

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continuous in ponds larger than 40 ha for a prolonged period of 15-21 days with the same

volume of water being drained from the fishpond to maintain a constant water level.

Sewage is added to the fishpond to stimulate sufficient plankton growth for fish feed but

care is taken to ensure that DO concentrations do not fall to the extent that fishes die.

Indian major carps stocked first are harvested between May to July, while those stocked

later are harvested during August to October. Silver carp are harvested in December. The

winter months are the safest months to dry and prepare the ponds but if fish culture

continues, fish harvesting also takes place at this time. The type of sein net selected

depends on the size of fish to be harvested. A typical harvesting team comprises 10-20 fish

farmers and a supervisor to provide general directions to optimize the haul. The fishes are

sorted in a boat and the harvested fishes are taken to the nearest auction market within two

hours by another group of workers and sold to "bidders" who take the fishes to retail

markets within another hour. There is no system of refrigeration or use of ice and the entire

harvest is sold fresh.

4.2 Uses of aquatic macrophytes in this culture system

Aquatic weeds like water hyacinth are grown along pond dikes of larger ponds to break

waves and prevent damage to dikes. In addition, these weeded areas, provide shelter to fish

when the temperature rises, prevent poaching of fishes to some degree and most

importantly serve as filters to extract nutrients and metals from the system. When these

weeds grow in excess, they are periodically harvested and decomposed in the pond to

enhance fertility of water. Surrounding these large ponds, silt traps 2-3 m wide and 30-40

cm deep are dug. These get filled with regular harvesting of fishes. Farmers restrict

themselves to cleaning of these silt traps instead of digging the entire pond. Silt rich in

nutrients is used for various purposes, including strengthening of dikes.

4.3 Disease problems

In sewage fed farms, bacterial diseases are not common. Even when there were problems

with Epizootic Ulcerative Disease (EUS) in recent years with carps in other areas, carps in

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these sewage-fed ponds remained uninfected. However, parasitic infections by Lernea

(Anchor Worm) and Argulus are common and there is a need to develop techniques for the

control of this problem.

5. Conditions of efficiency

For a bheri to be operated efficiently, the following conditions are critical-

a) Maintenance of the required depth of water at all the three stages of the production

process e.g. at nursery pond, rearing pond and stocking pond with proper inlet-outlet

management of sewage

b) Optimum quantity of sewage to be taken inside the pond

c) Availability of quality spawn/fry/fingerlings at required time

d) Proper and efficient deployment of working personnel

e) Monitoring fish health

6. Conclusion

Wastewater from the inner city of Kolkata with about 4.5 million people, an average daily

flow of wastewater of 1.1 million m3, is not treated by a conventional sewage treatment

plant but an estimated 30-50% of the sewage is treated by the maturation/ fish ponds of the

East Kolkata Wetlands. Sewage mainly enters the fish ponds during 270-300 days of the

year as the regulator gate at Bantala on the main sewage canals leading from the city is kept

closed during the dry season to raise the level of wastewater in the canals so it flows into

fish pond feeder canals and then into the ponds. However, the regulator gate is kept open

during the monsoon season to lower the water level in the main canals to prevent flooding

in the city.Fish production and profitability of the East Kolkata Wetlands ponds are

relatively low for semi-intensive fish culture compared to Andhra Pradesh. Some East

Kolkata Wetlands farms attain annual yields of 5-7tonnes/ha but mostly farms produce 3-5

tonnes/ha, only one third to one half of sustainable production from well managed semi-

intensive fish culture.

Training Compendium

106

The fisheries supply the city markets with 10-20 tonnes of fish per day, providing 10-20 per

cent of the total demand. In addition, some degree of natural treatment is applied to the

sewage and, in spite of the threat to the existing fisheries through urban development,

workers on the wetlands project feel that much more sewage could be handled in this way

and the greater part of Calcutta's demand for pond fish could be produced.

Fig 1: Eichornia crassipes in channels Fig 2: Large Sewage fed farm

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

Training Compendium

107

FAVORABLE RANGES OF WATER AND SOIL QUALITY PARAMETERS

FOR FISH FARMING AND HATCHERY OPERATION

S. K. Dubey & R. K. Trivedi

Department of Aquatic Environment Management

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences

Panchasayar, Kolkata-700094, West Bengal, India

1. Introduction

Water is the most important element for aquaculture. Selection of source water should be

based on its suitability for efficient production of a high quality aquaculture product. Poor

water quality may affect fish and shellfish health through impairment of development and

growth or may degrade the quality of the product by tainting its flavor or by causing

accumulation of high concentrations of toxic substances which could endanger human

health.

2. Source of Water

In general, for fresh water aquaculture, groundwater sources (springs and wells) are

preferred. They maintain a constant temperature, are free of biological nuisances such as

fish eggs, parasites and larvae of predatory insects and are usually less contaminated than

surface water sources.

3. Basic Factors

Fish and shellfish health is very sensitive to water quality. One set of parameters which

affect fish and shellfish are the basic characteristics of natural water otherwise referred to

as its physio-chemical properties. These include properties such as temperature, turbidity,

pH, and dissolved oxygen. It is also important to note that the water quality suitable for

hatchery, nursery, and grow-out systems for a particular species vary to some degree.

Training Compendium

108

3.1 Temperature: Water temperature affects a multitude of important processes.

Physiological processes in fish such as respiration rates, feeding, metabolism, growth,

behavior, reproduction and rates of detoxification and bioaccumulation are affected by

temperature. Temperature can also affect processes important to the dissolved oxygen level

in water such as the solubility of oxygen, and the rate of oxidation of organic matter.

3.2 Turbidity: Turbidity is a measure of light penetration in water. Turbid conditions result

from dissolved and suspended solids such as clay and humic compounds or

microorganisms such as phytoplankton. Turbid waters can shield food organisms as well as

cause gill damage and fish stress. It can also clog filters. Turbidity levels affect the light

available for photosynthesis by phytoplankton and the growth of undesirable organisms.

3.3 Alkalinity: Alkalinity is a measure of the acid neutralizing capacity of water and

subsequently prevents extreme pH shifts. If alkalinity is too low (less than 20 mg l-1), the

water may not contain sufficient carbon dioxide (CO2) or dissolved carbonates for

photosynthesis to occur, thus restricting phytoplankton growth.

3.4 pH: Natural waters range between pH 5 and pH 10. The pH of water used in

aquaculture can affect fish health directly. At lower pH, the species ability to maintain its

salt balance is affected and reproduction ceases. The pH can also indirectly affect fish and

shellfish through its effects on other chemical parameters. For example, low pH reduces the

amount of dissolved inorganic phosphorous and carbon dioxide available for phytoplankton

photosynthesis. Also at low pH, metal toxicity to fish and shellfish increases. At high pH,

the toxic form of ammonia becomes more prevalent. Low pH waters are often treated using

lime. Alum can be used to treat high pH waters.

3.5 Hardness (Calcium and Magnesium): Calcium is the most important component of

hardness to aquaculture. It is necessary for bone and exoskeleton formation and for

osmoregulation. Calcium hardness can be raised by adding agricultural gypsum or calcium

chloride.

Training Compendium

109

3.6 Dissolved Oxygen: Dissolved oxygen (DO) is a basic requirement for aquaculture. It is

usually the first limiting factor to occur in pond culture.

3.7 Carbon Dioxide: Diffusion from the atmosphere, fish respiration, and the biological

oxidation of organic compounds are the major sources of carbon dioxide in surface waters.

Extraordinarily high levels of carbon dioxide are of concern in aquaculture. When carbon

dioxide concentrations are too high, the blood CO2 levels of fish increase subsequently

impairing the ability of their hemoglobin to carry oxygen, and causing respiratory distress.

High carbon dioxide levels can also lower the pH, which as mentioned earlier can affect

fish adversely. Either calcium hydroxide, also known as slaked or hydrated lime, or sodium

carbonate may be added to reduce high levels of carbon dioxide. Vigorous mixing and

aeration is also a good method for removing excess carbon dioxide.

Table1. Advantages and disadvantages of common water sources

Source Advantage Disadvantage

River/stream May be readily

available

Inexpensive

Pumping costs lower

than wells

Typically requires pumping

Often have high silt loads

Can contain biological nuisances such as

parasites and larvae

of predatory insects

May contain contaminants

May contain excessive nutrient concentrations

Have seasonal and possibly diurnal fluctuations

in flow, temperature, and chemistry

Lake May be readily

available

Inexpensive

Pumping costs lower

than wells

Similar to river/stream, but chemistry is more

stable due to the buffering effect of the large

water volume

Bottom water may be anoxic in summer and

contain

reduced iron

Surface

runoff

Inexpensive May contain contaminants

Unreliable

Requires 5-7 acres of watershed per surface acre

of aquaculture water

Well Constant temperature

Usually less polluted

(see note)

Typically lacking oxygen and thus needs

aeration

Unless artesian, requires pumps which can be

Training Compendium

110

costly

May contain dissolved gases

May contain high iron concentrations or reduced

iron

Possible aquifer depletion

Municipal High quality Expensive

Typically have disinfecting chemicals which are

poisonous to

fish and expensive to remove

Wastewater Inexpensive Medium to high pathogen concentrations

May contain contaminants

Note: Although ground water has traditionally been less contaminated than surface water,

contamination of ground water sources has become common in industrialized nations. A

similar trend may be likely for newly industrializing countries of Asia. (Source: Swann

1993 and Lawson 1995)

Temperature range for aquaculture

28-300C – Optimal growth

<260C – Low growth

Turbidity tolerance levels for aquaculture

Effect Suspended solids concentration

No harmful effects on fisheries 25 mg l-1

Acceptable range 25-80 mgl-1

Detrimental to fisheries 80 mg l-1

Alkalinity tolerance levels for aquaculture

Total alkalinity (mg l-1) Effect

15-20 Phytoplankton

Training Compendium

111

production low

< 30 Poorly buffered against

rapid pH changes

20-400 Sufficient for most

aquaculture purposes

2100 or 150 Desirable

pH tolerance levels and effect for aquaculture

pH levels Effect

<4.0 Acid death point

4.0-5.0 No reproduction

4.0-6.5 Slow growth

6.5-9.0 Desirable range for fish

production

9.0-11.0 Slow growth

>11.0 Alkaline death point

Total Hardness

50.0-400.0 – For Warm water hatchery

Training Compendium

112

Recommended levels of dissolved oxygen for aquaculture

DO level Comment

>5.0 Recommended

>1.5 Live for several days

>1.0 Live for several

hours

<0.3 Lethal concentration

Carbon dioxide tolerance levels for aquaculture

Free CO2 level Comment

0 Ideal for Hatchery

<15 Warm water fish culture

Ammonia tolerances for aquaculture

For fresh water fish safe concentration is <0.05 mg/l of NH3 and < 1.0 mg/l of TAN

Optimal sediment characteristics for aquaculture

Valuable and range Potential for fish

production

pH <5.5 Low

5.5-6.5 Average

6.5-7.5 High

Training Compendium

113

7.5-8.5 Average

>8.5 Low

Available

phosphorus

<30mg/l Low

30-60 mg/l Average

>60 mg/l High

Available Nitrogen >250 mg/l Low

250-750 mg/l High

Organic Carbon <0.5 mg/l Low

0.5-1.5 mg/l Average

1.5-2.5 % High

>2.5 % Low

Protecting aquaculture ponds from pesticides

Place ponds a considerable distance from pesticide treated fields.

Plant trees or other tall plants between pesticides treated fields and aquaculture

facilities to intercept airborne drift of sprayed pesticides.

Construct topographic barriers (ditches or terraces) to prevent agricultural runoff

from entering ponds.

Use proper methods of pesticide application to fields.

Properly dispose of all pesticides and pesticide containers.

Training Compendium

114

Table 2. Favorable range of water quality parameters for Aquaculture

Sl.No. Parameter Fresh water Brackish water Seawater

1 Colour Clear water

with greenish

hue <100

colour units

Clear water with

greenish hue

<100 colour units

Clear water with

greenish hue

<100 colour

units

2 Clay Turbidity

(mg/l)

<30 <30 <30

3 Temperature (0C)

Tropical Climate 25-32 25-32 25-32

Temperate climate 10-12 10-12 10-12

4 pH 7.5-9.5 8.0 -8.7 8.0-8.5

5 Solids (mg/l)

Total Solid <500 >500 >500

Suspended Solid 30-200 25-200 25-200

6 Dissolved Oxygen

(mg/l)

5-10 5-10 5-10

7 Total dissolved free

Carbon Dioxide

(mg/l)

<3 <3 <3

8 Hardness (mg/l) 30-180 >50 >50

9 Alkalinity (mg/l) 50-300 >50 >50

10 Chlorides (mg/l) 31-50 >500 >500

11 Salinity (ppt) <0.5 10-25 >30

12 Ammonia Nitrogen (NH3-N), (mg/l)

Unionized (NH3) 0-0.1 0.0.1 0-0.1

Ionized (NH4+) 0-1.0 0-1.0 0-1.0

13 Nitrite Nitrogen

(NO2-N), (mg/l)

0-0.5 0-0.5 0-0.5

14 Nitrate Nitrogen

(NO3-N),(mg/l)

0-1-3 0-1-3 0-1-3

15 Total Nitrogen

(mg/l)

0.5-4.5 0.5-4.5 0.5-4.5

16 Total Phosphorous

(mg/l)

0.05-04 0.05-0.5 0.05-0.5

17 Potassium (mg/l) 0.5-10 >0.5 >0.5

18 Calcium (mg/l) 75-150 >75 >75

19 Magnesium (mg/l) 20-200 200-1350 >1350

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20 Sulphate (mg/l) 20-200 200-885 >885

21 Silica (mg/l) 4-16 >5 >5

22 Iron (mg/l) 0.01-0.3 0.01-0.3 0.01-0.3

23 Manganese (mg/l) 0.001-0.002 0.002-0.02 0.002-0.02

24 Zinc (mg/l) 0.002-0.01 0.002-0.01 0.002-0.01

25 Copper (mg/l) 0.003-0.005 0.003-0.005 0.003-0.005

26 Cobalt (mg/l) <0.003 <0.003 <0.003

27 Biochemical Oxygen

Demand (B.O.D.)

(mg/l)

<10 <15 <15

28 Chemical Oxygen

Demand

(C.O.D.)(mg/l)

<50 <70 <70

29 Hydrogen sulphate

(mg/l)

<0.002 <0.003 <0.003

30 Residual chlorine

(mg/l)

<0.003 <0.003 <0.003

31 Primary productivity

(mg C/m3/day)

1000-3000 1000-2500 1000-2500

32 Plankton (ml/100

litre)

2 1 1

33 Chlorophyll - a (μgl-

1)

20-275 20-250 20-250

34 Redox - potential

(volts)

0.40-0.52 0.40-0.52 0.40-0.52

35 Organic carbon in

sediment (%)

0.50 – 2.75 0.50 – 2.75 0.50 – 2.75

Table 3. Favorable range of soil quality parameters for Aquaculture

Sl.No Parameter Range

1 Soil Nature Sandy-clay-Loam

2 Soil Colour Blackish brown

3 pH 6.0-8.0

4 Water Retention Capacity 40% and above

5 Sand:Silt:Clay 40:30:30

Training Compendium

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6 Total Nitrogen 50mg/100gm of soil sample

7 Total Phosphorous 6mg/100gm of soil sample

8 Potassium 25mg/100gm of soil sample

9 Organic Carbon 0.5% and above

10 Electrical Conductivity Lesser than 16 millinhos/cm

Paper prepared for International Training Programme on Freshwater Fish Seed Production, Nursery and Rearing Practices for Cambodian Delegates; Organised by Faculty of Fishery Sciences, West Bengal University of Animal & Fishery sciences, Kolkata, India during 05-10 Nov, 2012

PRESENT STATUS OF FISHERIES

IN WEST BENGAL

Dr. Goutam Chandra SarkarEx. Joint Director of Fisheries

Fisheries Dept. WB

Annex I

Fishery Resources In West Bengal

Sl. no. Type of fishery

Total potential

resource

(In lakh ha)

Under culture

(In lakh ha)

Percentage of

resource area

under culture

1. Ponds / Tanks 3.12 2.87 91.99

2. Beel & Boar 0.41 0.21 51.21

3. Reservoir 0.27 0.13 48.15

4. a) River 1.90 - -

b) Canal 0.83 - -

5. Sewage fed fishery 0.04 0.04 100.00

6. Brackish water fishery 2.10 0.58 27.62

Sl. no. Marine environment Area

1. Inshore area (Up to 10 fathom depth): 777 Sq. km

2. Offshore area (10-40 fathom depth): 1813 Sq. km

3. Continental shelf (Up to 100- fathom depth): 17049 Sq. km

4. Coast line 158 km

MAP OF WEST BENGAL

Salient Features of Fisheries

in West Bengal

West Bengal is the highest fisheries resources & highest

percentage of fish consuming population in the country.

Fisheries represent a very vital sector in State Government's

thrust programme for generation of rural employment along with

the socio-economic improvement of the fisher folk of the state.

In rural areas, the economic benefits that can accrue through

improved pisciculture.

Successful infusion of scientific eco-friendly technology

through three tier training system viz. State level training, District

level training and Block level training.

Simultaneously, undertaking infrastructure development and

welfare measures for fisher folk to improve their socio-economic

status.

Fish Seed Production : West Bengal is the pioneer and leader in

fish seed production in India. In the year 2010-11 West Bengal

produced 13453 million of fish seed, contributing about 62% of the

total production o fish seed in the country.

Fish Production: In the year 2010-11 West Bengal produced 14.43

lakh MT fish against demand of 14.85 lakh MT. Position of West

Bengal is highest (29%) among the inland fish producing states in

India.

Export: At the end of 2010-11, quantum of export of marine food

products was about 51256 MT whose export value was about Rs.

1116.11 crore

Employment Generation:: At the end of 2010-11, 79178 units of

employment have been generated in fisheries sector

Field of Fish Production in West Bengal

Culture fishery Capture fishery

Fresh water fishery

Sewage fed fishery

Brackish water fishery

Cold water fishery

Ornamental fishery

River, creek & canal

Sea

Inland Fishery Sector In West Bengal

Fish Production in West Bengal (2010 - 2011)

14.43 lakh MTInland:

12.46 lah MT

Marine:

1.97 lakh MT

Fish seed production in WB (2010-11)

13453 million

594 fish seed hatcheries in WB

A) Freshwater:

(i) Extension support to the fishermen for aquaculture through improved technology and

imparting Training to the farmers.

(ii) Ensuring availability of input, viz. fish seed, feed, fertilizer etc.

(a) Encouraging fish seed production in the private sector by promoting Hatcheries for

Indian Major Carp (IMC), exotic carp, Magur, Giant prawn and different threatened fish

species etc.

(b) Encouraging fish seed production in the private sector by promoting hatcheries for

ornamental fisheries and crab.

(iii) Facilitating financial assistance-Bank credit and Government subsidy–to the

Pisiculturists for commercial production through FFDA and Short Term Credit

Programme (STCP).

(iv) Uplifting the economic condition of fishers and encouragement for aquaculture instead

of capture fishery in certain areas.

Initiatives taken for development of Inland

Fisheries

v) Encouraging the Fishermen's Co-operative Societies, Fish Production Groups and

Self Help Groups.

(vi) Establishing backward and forward linkages to facilitate supply of inputs for fish

culture and marketing of fish.

(vii) Construction of fishermen’s housing, link roads, Markets, flood shelter, community

centers model village, and to provide Insurance cover to them.

B) Brackish water:

I. Training of farmers and extension work for disseminating the improved method of

brackish water aquaculture.

ii. Providing financial assistance to the farmers for encouraging setting up of new

brackish water farms, re-modeling the existing farms on improved methods

maintaining norms of the Aquaculture Authority, through B.F.D.A.

TYPES OF SCHEMES UNDER FISHERIES SECTOR

Central Government

Assistance Schemes

State Government

Assistance Schemes

Centrally sponsored Schemes

Central Sector Schemes

Special Central assistance

schemes relating to Fisheries &

other activities

State Govt. makes the

fisheries schemes according

to the need of the State.

LIST OF CENTRALLY SPONSORED SCHEME UNDER

FISHERIES SECTOR

1. Development of Inland Fisheries and Aquaculture”

2. “Development of Marine Fisheries, Infrastructure and Post

Harvest Operations”

3. National Scheme of Welfare of Fishermen

LIST OF CENTRAL SECTOR SCHEME

UNDER FISHERIES SECTOR

1. Strengthening of Database and Geographical Information

Networking for the Fisheries Sector:

SPECIAL CENTRAL ASSISTANCE SCHEMES

RELATING TO FISHERIES & OTHER ACTIVITIES

a) National Fisheries Development Board (NFDB)

b) Rashtriya Krishi Vikas Yojana (RKVY)

c) National Rural Employment Guarantee Act (NREGA) {Mahatma

Gandhi National Rural Employment Guarantee Act (MGNREGA }

SCHEME FOR FISHING

REQUISITES

INFRASTRUCTURAL

SCHEME

WELFARE

SCHEMEDEPARTMENTAL

SCHEMES

SCHEME FOR

AQUACULTUREDistribution of

Minikit

Composite fish

culture

Social

Fisheries

Integrated fish

farming

Air breathing

fish culture

Ornamental

fish cultureCrab

Culture

Fresh water and Brackish

water prawn culture

Nursery and rearing

of carp

Old Age

Pension

Nets and

HundiesBoats

Link Rods Community Hall Tube Wells Fish Market Ice Plant

TRAINING

Model Village

Welfare schemes

(A) Housing Programme

Fisheries department started providing housing facilities to 50 poor fishermen families through state

budget. 12797 houses have been constructed under Rural Landless Employment Guarantee Programme

(RLEGP) (Later termed Indira Awas Yojona). Development of model villages for fishermen and tribal people

under the Centrally Sponsored National Welfare Fund schemes was initiated and 6188 houses along with

facilities such as tube well, community hall have been provided. 18627 houses have been constructed and

handed over to tribal families.

B) Pension Scheme

This scheme was started in the year 1991-92 to extend help to old and infirm fishermen. At present pension

of @ Rs. 1000 month-1 person-1 is provided to 7250 fishermen under this scheme.

(C) Fishermen Group Personal Accident Insurance for Active Fishermen

This scheme was started in the year 1984-85. The families of fishermen are issued for a sum Rs. 1,00,000/-

for the death or permanent disablement and Rs. 50,000/- for partial disablement due to accident. The

premium is Rs. 14/-only annum-1 head-1 on 50:50 share basis by State and Central Govt.

(E) Savings –Cum -Relief Scheme

A marine fisherman is required to deposit @ Rs.75 for 8 months during fishing period. State & Central Govt.

of India share equal amount. The accumulated deposit of Rs.1800/- is returned to marine fishermen @

Rs.450.00 month-1 during non-fishing period of four months.

Annex II

Photo Sheet of Training

Annex III

INTERNATIONAL TRAINING PROGRAMME FOR CAMBODIAN TRAINEES

FACULTY OF FISHERY SCIENCES WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES, KOLKATA

TRAINING SCHEDULE

Date Time Place of visit Purpose of visit Person In-charge 5.11.12 10.30-11.30 Inauguration programme Dr S K Rout

11.30-12.00 Orientation Dr R K Trivedi

12.00-12.30 Presentation on overview of West Bengal fishery Dr S. N. Biswas

12.30-13.15 An overview of Aquaculture development in Cambodia Mr M Sato

13.15-14.00 Lunch

14.30-16.30 Visit to 4 No. Bhery

Co-operative society

To get the knowledge of co-

operative fishery working system

Mr Supratim

Choudhury

6.11.12 9.00 -12.00 Visit to ornamental fish

farms at Pailan & Amtala

To get the knowledge about

ornamental fish breeding and

culture

Dr T K Ghosh

12.30-14.00 Visit to Mudially Fisheries

Co-operative Soc

To see the culture practices in

large water body ( Common Carp,

Grass Carp & IMC)

Mr Supratim

Choudhury

14.00 Lunch (at Mudially)

15.30-17.00 Visit to Central Institute of

Fisheries Education,

Kolkata centre

Practical demonstration class Dr B K Mahapatra

7.11.12 4.30-6.30 Visit to Naihati fish seed

market

To see the India’s largest fish seed

marketing

Dr G Dash

7.00 Breakfast (at Biswas Hatchery)

7.30-13.00 Visit to hatcheries &

farms near Naihati

To see the hatchery operation, to

get the knowledge about nursing

techniques and to see the farming

practice by small scale farmers

(Pangasius, Mrigal, Grass carp )

Prof N R Chatterjee

Dr G Dash

13.30 Lunch at Barrackpore

14.00 Return to Hotel

8.11.12 9.00-13.00 Visit to sewage- fed

fishery at East Kolkata

Wetland and Bhery

To observe the sewage – fed

aquaculture system, Tilapia,

Common carp, Mrigal, Silver

carp, etc.)

Prof. S S Dana &

Dr S K Rout

13.30 Lunch (at Shivraj Farm)

14.30-18.30 Visit to Science City, Kolkata Mr S. K. Dubey

9.11.12 10.00-13.00 Visit to Central Inland

Fishery Research Institute

(CIFRI)

To understand the role and

function of fishery/aquaculture

institute and on-farm

demonstration

Dr G Dash

13.30 Lunch (at CIFRI)

14.30-15.30 Visit to Neelganj

ornamental fish farm

To see the culture of high value

ornamental fishes

Dr G Dash

10.11.12 8.30-18.30 Visit to Sundarban

Mangrove forest area and

brackish water/freshwater

fish farm

To see the brackish water-

freshwater fish culture and to see

the farming practice by small

scale farmers

Dr B K Chand

Mr S. K. Dubey

Breakfast & Lunch on board the vessel

Annex IV

List of Participants Attending International Training Programme on

“Freshwater Fish Seed Production and Nursery Rearing in West Bengal,

India”

Organized by

Faculty of Fishery Sciences,

West Bengal University of Animal and Fishery Sciences, Kolkata, India

On

5th

to 10th

November, 2012

Sl No. Name Address E-Mail Id

1 Dr. Hav Viseth Phnom Penh, Cambodia viseth9@hotmail.com

2 Mr. Pol Mimosa Phnom Penh, Cambodia polmimosa@yahoo.co.uk

3 Mr. Kong Sokha Battambang, Cambodia kongsokha51@yahoo.com

4 Mr. Prin Savin Siem Reap, Cambodia prinsavin@camintel.com

5 Mr. Mith Phan Battambang, Cambodia

6 Mr. Mao Pek Battambang, Cambodia

7 Mr. Pouk Chhan Siem Reap, Cambodia

8 Ms. Say Rathna Siem Reap, Cambodia

9 Ms. Chuop Sisavann Pursat, Cambodia

10 Mr. Ly Heng Pursat, Cambodia