Post on 22-Mar-2023
LESSON SIX: How Do We Get Better Pigs?
LESSON SIX: How Do We Get Better Pigs?
Standards AS.01.01.01.a. Identify and summarize the origin, significance, distribution, and domestication of different animal species.
AS.01.01.02.c. Predict trends and implications of future developments within different animal industries on production practices and the environment.
CRP.04.01.02.b. Apply strategies for speaking with clarity, logic, purpose, and professionalism in a variety of situations in formal and informal settings.
AS.04.02.02.a. Identify and summarize inheritance and terms related to inheritance in animal breeding (e.g., dominate, co-dominate, recessive, homozygous, heterozygous, etc.).
AS.04.02.01.a. Summarize genetic inheritance in animals.
AS.04.03.01.a. Identify and categorize natural and artificial breeding methods (e.g., natural breeding, artificial insemination, estrus synchronization, flushing, cloning, etc.).
AS.04.03.04.a. Examine the use of quantitative breeding values (e.g., EPDs, performance records, pedigrees) in the selection of genetically-superior breeding stock.
CRP.04.02.01.a. Research and summarize the purpose of different forms of written and visual communication in formal and informal settings (e.g., letters, emails, reports, social media, graphics, diagrams, etc.).
CRP.04.03.02.a. Observe and identify use of active listening strategies in formal (e.g., speeches, presentations, etc.) and informal (e.g., conversations, meetings, etc.) settings.
CS.05.02.01.a. Examine and categorize careers in each of the AFNR pathways.
LESSON SIX: How Do We Get Better Pigs?
Student Learning Objectives
Slide 102 in DPPI6 How Do We Get Better Pigs?
Lesson Objective: Students will explain how to improve pigs using breed characteristics and genetics.
Enabling Objectives As a result of this lesson, the student will…
1. Explain the primary breeds of pigs and where/how they developed.2. Identify characteristics that are considered in order to breed for improved
pigs.3. Analyze how advances in breeding and genetics have impacted the pork
industry.4. Explain the career of a reproduction technical support specialist.
Summary/Guide In this two-day lesson, students take a deep dive into the primary breeds of pigs (Yorkshire, Duroc, Hampshire, Landrace, Berkshire, Spotted, Chester White, and Poland China) and where they were developed. Students will come up with creative ways to remember each breed and key facts. In objective two, students will explore breeding systems and the traits the pork industry breeds for in today’s pigs. To conclude the day, students will use their Career Highlight Worksheets to take notes during the career video on a reproduction technical support specialist career and complete questions on the Then-Now-Future chart about breeds and breeding systems.
Objective three is covered on day two where students will explore Expected Progeny Differences (EPDs) and other advances in genetics to further improve the pork industry. Students will compare photos of pigs from 50 years ago to pictures of pigs of today and note what is similar and different. They will then identify how some of these changes are related to genetics.
To conclude the lesson, students will return to the Then-Now-Future chart (either on the wall or on a PowerPoint slide) to reflect on the role genetics will play in pork production in the next 50 years.
To Complete Prior to the Lesson: Provide Career Highlight Worksheet for students AS6.1A-D – Breed Identification Cards printed out (one classroom set)
LESSON SIX: How Do We Get Better Pigs?
AS6.2A-B – Genetics Matching Cards printed and cut out, one set per groupsof three to four
AS6.3 – Pigs & Genetics Statements printed and cut out, one statement pergroup
AS6.4 – EPD Activity Sheet
Time: 45 minutes
List of Resources American Berkshire (n.d.). Founded in 1875. Retrieved from
https://americanberkshire.com/history/
Certified Pedigree Swine (n.d.) Breeds | Chester White. Retrieved from http://cpsswine.com/chester-white/
Certified Pedigree Swine (n.d.) Breeds | Poland China. Retrieved from http://cpsswine.com/poland-china/
Certified Pedigree Swine (n.d.) Breeds | Spotted. Retrieved from http://cpsswine.com/spotted/
National Swine Registry (n.d.). Ideal Duroc Features. Retrieved from https://nationalswine.com/resources/docs/education/ideal_flyers/duroc_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Hampshire Features. Retrieved from https://nationalswine.com/resources/docs/education/ ideal_flyers/hampshire_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Landrace Features. Retrieved from https://nationalswine.com/resources/docs/education/ ideal_flyers/landrace_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Yorkshire Features. Retrieved from https://nationalswine.com/resources/docs/education /ideal_flyers/yorkshire_ideal_flyer.pdf
List of Tools, Equipment, and Supplies • USPCE Lesson 6 PowerPoint• Presentation Pork Pages• Teacher Activity & Resource Packet
LESSON SIX: How Do We Get Better Pigs?
• Career Highlight Worksheet• Crayons, colored pens, pencils, highlighters (any type of colored pen)• Poster board• Tape• Breed Identification Cards• Genetics Matching Cards• Pigs & Genetics Statements
Key Terms
Slide 103 in DPPI6 How Do We Get Better Pigs? The following terms are presented in this lesson (shown in bold italics). Definitions for these words can be found in the Teacher Activity and Resource Packet.
• Rebreeding interval• Terminal crossbreeding program• Feed efficiency• Terminal/Paternal sire• Marbled• Rate of gain• Breeding systems• Purebred breeding• Crossbreeding• Heterosis (hybrid vigor)• Genetics• Trait• Gene• Genotype• Phenotype• Dominant• Recessive• Hereditary• Expected Progeny Difference (EPD)• Progeny
LESSON SIX: How Do We Get Better Pigs?
Connection to Prior Knowledge
Ask students: Reflect back on what we learned
yesterday and why pigs act the waythat they do. What is one key factyou remember from yesterday?
Explain that the breed of a pig and its genetics also influence how a pig acts. Today, we are going to explore the breeds of pigs, their history, and breeding systems to get the best pigs.
Interest Approach
Instruct students to close their eyes. • Ask: What do you see when I
say the word ‘dog?’ (studentscan open eyes now)
o Listen for: kind of dog,size, color, uniquecharacteristics, etc.
• Capture responses on board
Ask students to list the breeds they know and some of their key characteristics.
• Listen for: size, color, ears,temperament, etc.)
Explain that there are many breeds of dogs in the world with some that are more familiar than others. The same concept applies to pigs.
Ask: Why do you think understanding pig breeds and their unique characteristics is important for pig farmers?
Summary of Content and Teaching Strategies
Teaching Strategies Related Content
LESSON SIX: How Do We Get Better Pigs?
• Listen for: meat quality,temperament, maternalcharacteristics etc.
Explain that we are going to explore the eight most common pig breeds in the U.S. and what they are known for/why a farmer might choose to raise that breed.
Content: Objective 1 – Breeds of Pigs
Slide 104 in DPPI6 How Do We Get Better Pigs?
Think-Pair-Share: Instruct students to pair up and discuss the following question:
• Why do you think farmers wanthealthy and strong animals?
Slide 105 in DPPI6 How Do We Get Better Pigs?
Have a few groups share their ideas.
Instruct students to think about the word “better” in terms of pigs.
• Ask: What does it mean to get“better” pigs?
• Lead class discussiono Note: Discuss “better” in
terms of strong, healthy,content, etc.
Using Pork Page 23, instruct students to capture the definition of “better” as it relates to the pork industry.
Better as it relates to the pork industry: Improving a specific trait based on production goals
LESSON SIX: How Do We Get Better Pigs?
Slide 106 in DPPI6 How Do We Get Better Pigs?
Explain that pork producers get “better” (healthy and strong) pigs starting with breeding. Pigs today are a result of the development and improvement of breeds over the years. We are now going to explore those breeds.
Instruct students to get into groups of eight. Using AS6.1A-D, pass out one breed identification card to each group.
Using the following websites, instruct students to use the next 15 minutes to research their assigned breed and develop a two-to-three-minute presentation. Presentation should include history of the breed, characteristics, what they are known for, etc. and a clever way to help us remember the breed (song, dance, rhyme, poem, jingle, etc.). Presentations can be created on poster board or PowerPoint.
• https://www.pork.org/facts/pig-farming/major-swine-breeds/
• https://americanberkshire.com/history/
• http://cpsswine.com/chester-white/
• http://cpsswine.com/poland-china/
• http://cpsswine.com/spotted/• https://nationalswine.com/
resources/docs/education/ideal_flyers/duroc_ideal_flyer.pdf
Yorkshire: • White with erect/upright ears• Originated in England• Known as “The Mother Breed” – excel
in litter size, birth and weaning weight,rebreeding interval, durability, andlongevity
• Boars and females used asGrandparents in production of femalesused in terminal crossbreedingprogram
• High proportion of lean meat and lowbackfat
Duroc: • Red with drooping ears• Range from very light golden (almost
yellow color) to very dark red• Developed from crossing Red Durocs in
New York City and Jersey Reds fromNew Jersey
• Market pigs excel in durability, growth,and muscle quality attributes
• Competitive for carcass leanness andfeed efficiency
• Duroc sires most often used asTerminal/Paternal sire in terminalcrossbreeding program
LESSON SIX: How Do We Get Better Pigs?
• https://nationalswine.com/resources/docs/education/ideal_flyers/landrace_ideal_flyer.pdf
• https://nationalswine.com/resources/docs/education/ideal_flyers/yorkshire_ideal_flyer.pdf
Slide 107 in DPPI6 How Do We Get Better Pigs?
As students present their breed, instruct them to use Pork Page 6.1 to take notes on each breed. Display information on the PowerPoint to help students capture more information on each breed.
Slide 108-120 in DPPI6 How Do We Get Better Pigs?
• Black with a white belt across theshoulders and around body; alsocovers the front legs
• Erect ears• Originated in southern Scotland and
Northern England• Lean muscle with good carcass quality,
minimal amount of backfat and largeloin eyes
• Sows known as great mothers• Proven record of increased durability
and robustness• Contribute to superior carcass
composition of the commercial markethog.
Landrace: • White in color• Large ears which droop and slant
forward• Originated from Danish Landrace in
Denmark• Crosses well with other breeds• Excel in litter size, birth and weaning
weight, rebreeding interval, durabilityand longevity
• Used as Grandparents in production ofparent stock; females used in terminalcrossbreeding program
• Long-bodied, high percentage ofcarcass weight in ham/loin
Berkshire: • Black body with six white points (tip of
tail, nose and four legs)• Erect ears• Originated in England• Known for producing a whole carcass
that is well marbled• Pork is consistently sweet, tender, and
palatable
Hampshire:
LESSON SIX: How Do We Get Better Pigs?
Explain that now that we understand the eight major breeds and their important characteristics, we are going to explore breeding systems and how farmers breed for better (stronger and healthier) pigs.
• Records show that the Berkshirebloodstream has been pure for 200years
Spotted: • Large black and white spots• Drooping ears• Parts of ancestry traced to Poland
China – breed originated in Indiana• Continue to improve feed efficiency,
rate of gain, and carcass quality• Ability to transmit fast-gaining, feed-
efficient meat qualities to offspring
Chester White: • White• Droopy, medium-sized ears• Originated in Chester County,
Pennsylvania• Excel in mothering ability, durability,
and structural soundness• Packers prefer muscle quality of
Chester White
Poland China: • Black with six white points• Drooping ears• Originated in Ohio• Big-framed, long-bodied, lean, and
muscular• Excellent feeders and quiet
dispositionNote: See more information on each of the breeds in the Teacher Activity & Resource Packet.
LESSON SIX: How Do We Get Better Pigs?
Objective 2 – Breeding Systems
Slide 121 in DPPI6 How Do We Get Better Pigs?
Using Pork Page 6.2 and the information from the PowerPoint, instruct students to fill in the guided notes as you walk through the information.
• Note: the bolded, underlinedwords are the ones students willbe filling in.
Slide 122-123 in DPPI6 How Do We Get Better Pigs?
Explain that breeding systems consist of two types of mating: purebred breeding and crossbreeding. Instruct students to continue filling in the guided notes on Pork Page 6.2. The bolded, underlined terms are the words students will be filling in.
These eight breeds, and all other pig breeds, emerged because there was (and is) a need for better, or more improved, pigs.
Improvement of pigs is based on the outcomes farmers need/want. Improving a specific trait based on production goals. Examples include:
• Pork quality (marbling, color,leanness)
• Better mothering abilities• Faster and more efficient growth
There are systems of breeding that help pig farmers get improved traits in pigs produced.
Breeding systems (aka, mating systems): Breeding or mating systems are the approach taken to pair a boar and a gilt or sow for breeding in order to incorporate or maintain desired traits. Because the genetics of a pig plays an important role in its performance and meat quality, all pig producers should be familiar with breeding systems for pigs.
Purebred breeding: • Mating two animals of the same breed
in which a certain number of geneticlines are available
LESSON SIX: How Do We Get Better Pigs?
Slide 124-126 in DPPI6 How Do We Get Better Pigs?
Explain that breeding systems are what pig farmers purposefully use to get improved traits and characteristics in pigs and advance the pork industry.
Explain that now that we understand breeds, purebred breeding, crossbreeding, and the reasons for each, we are going to explore a career that works directly in this sector of the pork industry.
• This results in purebreds of a specificbreed (Yorkshire, Hampshire, etc.)
• Reasons someone would choose tobreed purebreds:
o To capitalize on heterosiso For seedstock productiono To take advantage of breed
characteristics. Example: Berkshires are
known for superiormeat quality
Crossbreeding: • Mating animals of different breeds• Crossbreeding animals with desired
traits is an attempt to maximizeheterosis, the ability of the offspring tooutperform their parents
• Results in improved performance,growth, and/or carcass traits.
• Reasons someone would choosecrossbreeding:
o Utilize best pig breedso Take full advantage of
strengths of different breedso Improve genetics and healtho Most often used in market
Career Highlight
Slide 127 in DPPI6 How Do We Get Better Pigs?
Remind students about the Career Highlight Worksheets. Explain that they will complete one of these worksheets during the career highlight video in each lesson and then store them with their Pork Pages. Encourage students to be intentional about
LESSON SIX: How Do We Get Better Pigs?
careers that interest them and writing down steps to learn more/follow up.
Before playing the video, instruct students to write down two surprising/interesting facts and one question they have in their Career Highlight Worksheets while watching the career spotlight video.
After video, take three to four minutes to debrief by having students share their notes and answer a few of the questions.
Other debriefing questions could include:
1. What does a reproductiontechnical support specialist do?
2. What is a unique aspect of thisjob?
3. What advice did this personoffer for getting into thiscareer?
Play career video.
Ticket Out the Door: Then-Now-Future
Return to the Then-Now-Future chart either on the wall or the PowerPoint.
Instruct students to reflect back on this lesson using the following questions and to respond in the corresponding columns using one of the methods described above.
• In the “Now” column, respond to the following prompt:o Capture key facts about the different breeds, breeding systems, and
genetics.
• In the “Future” column, respond to the following question:o Breeds and breeding systems have been continuously changing. How
do you think they will change in the next 50 years?
Slide 128 in DPPI6 How Do We Get Better Pigs?
LESSON SIX: How Do We Get Better Pigs?
DAY TWO:
Slide 129 in DPPI6 How Do We Get Better Pigs?
Teaching Strategies Related Content Interest Approach
Using the PowerPoint, show pictures of pigs (both production/commercial and from fairs/livestock shows) from 50+ years ago to current day.
Instruct students to observe the pictures and identify changes noticed as time progresses. Also, note any similarities they notice over the years.
Slide 130-133 in DPPI6 How Do We Get Better Pigs?
Lead a short class discussion on the similarities and differences they noticed. Then, explain how we will be taking a look into how advances in breeding and genetics have brought us the pigs we have today.
Content: Objective 3 – Advances in Breeding and Genetics
Slide 134 in DPPI6 How Do We Get Better Pigs?
Quickly list each of the eight breeds researched yesterday and ask students to recall one unique thing about each breed.
LESSON SIX: How Do We Get Better Pigs?
Ask: If you had a farm, which breed would you select and why?
Using Pork Page 6.2 and the information from the PowerPoint, instruct students to complete the guided notes on breeding systems and genetics.
• Note: the bolded, underlinedwords are the ones studentswill be filling in.
Slide 135 in DPPI6 How Do We Get Better Pigs?
Ask: Reflect back on what you have learned in other classes or experiences and share with us what genetics means.
Instruct students to get into groups of three to four. Using AS6.2A-B, pass out a set of the Genetics Matching Cards to each group.
Instruct students to use the next 90 seconds to match the term to its correct definition. Tell them to use their best guess if they don’t know the answers and we will review them once time is up.
Once time is up, review the correct answers on the PowerPoint. Instruct students to use Pork Page 6.2 to capture these definitions.
Slide 136-138 in USPCE6 How Do We Get Better Pigs?
• Breeds and breeding systems are howproducers improve production traits inpigs.
• Advances in breeds go hand-in-handwith genetics.
• This impacts the pork industry.
Genetics Matching Cards: • Genetics: the study of differences in
resemblance between individuals as aresult of variation in genes
• Trait: Characteristics expressed bygenes and/or influenced byenvironment; include physical andbehavioral
LESSON SIX: How Do We Get Better Pigs?
Using Pork Page 27 and the information from the PowerPoint, instruct students to complete the guided notes on genetics.
• Note: the bolded, underlinedwords are the ones studentswill be filling in.
Slide 139 in DPPI6 How Do We Get Better Pigs?
Instruct students to reflect back on their list of differences and similarities from the Interest Approach. Lead a class discussion using the following questions and prompts.
• Review their lists.• How are these changes related
to genetics?• What are some of the traits?• Which observed changes are
due to genotype? Phenotype?
• Gene: Part of DNA that carrieshereditary information passed fromparents to offspring
• Genotype: Internal hereditaryinformation that contains genetic code
• Phenotype: Outwardly-expressed traitsor characteristics
• Dominant: Expresses (shows) a specifictrait even if only one parent passed thegene to offspring
• Recessive: Requires the same genefrom both parents in order to beexpressed in the offspring
• Hereditary: Passed or capable of beingpassed from parent to offspring bymeans of genes
• Genetics involves genotype andphenotype. A genotype is the geneticcode for the phenotype (what is seen).
o Example of a phenotype: floppyears vs erect ears
• Genes can be dominant or recessive.o Example: Breeding a pig with
floppy ears to a pig with erectears results in offspring withfloppy ears because the genefor floppy ears is dominant andthe gene is erect ears isrecessive.
LESSON SIX: How Do We Get Better Pigs?
Divide students into three groups. Using AS6.3, pass out one statement to each group. Explain each statement is factual and they are going to analyze the truth to the statement. Instruct students to use the next three minutes to complete the following and be prepared to share with the class:
• Read their statement (will alsobe read out loud when sharedwith class)
• Analyze how genetics is a partof the statement
• Write a scenario that goesalong with the statement withspecific examples of a farmerand his decision-makingprocess in getting “better”(stronger and healthier) pigs.
Once time is up, instruct each group to share with the class. As each group is sharing, display the statement on the PowerPoint.
Note: All three of the above statements are factual. Additional information on each statement is provided in the Teacher Activity & Resource Packet.
Slide 140-143 in DPPI6 How Do We Get Better Pigs?
Group 1: As pigs have changed and evolved over the years, pig farmers use breeding systems (mating systems) to specifically improve characteristics (many of which we visually see) including a pig’s ability to yield high-quality meat.
Group 2: Feed efficiency – future increased productivity of pigs is linked to efficiency, which means pig farmers need pigs with the built-in ability to convert feed into muscle even more efficiently and grow faster at the same time.
Group 3: Pig farmers who thoroughly understand genetics and utilize improved genetic evaluation techniques will be able to improve production efficiency and lower their production costs. This allows them to stay competitive in today’s changing pork industry.
LESSON SIX: How Do We Get Better Pigs?
Genetics play a big role in getting better pigs and there is a tool to help pig farmers identify specific traits they want to improve. The tool is called Expected Progeny Differences (EPDs).
Using Pork Page 6.2 and the information from the PowerPoint, instruct students to complete the guided notes on Expected Progeny Differences.
• Note: the bolded, underlinedwords are the ones studentswill be filling in.
Slide 144-146 in DPPI6 How Do We Get Better Pigs?
Notes on Expected Progeny Differences (EPDs):
• A tool used to help pig farmers identifygenetic traits to improve their herd isExpected Progeny Differences (EPDs)
• EPD definition: How the animal’soffspring will perform compared to theoffspring of another boar (sire) or sow(dam) within the same breed
• Using EPDs, producers can select boars(sires) and sows (dams) that willproduce pigs with the productiontraits/characteristics desired to makeimprovements to the next generation
• Areas that EPDs include are: backfat,number born alive, litter weight, feedconversion
• EPDs are good measurements ofgenetic value because they areadjusted for the different amounts ofinformation available for each animal(number of records, progeny,heritability, etc.)
• EPD Example:o EPD litter weaning weight – Sow
A: +3.2 pounds. Sow B: 0pounds. This means Sow A’s
daughters would likelyhave litter weights that
LESSON SIX: How Do We Get Better Pigs?
Optional Activity: Using the PowerPoint and AS6.4, instruct students to take two minutes to review and answer the corresponding questions for EPD example #1.
Slide 147 in DPPI6 How Do We Get Better Pigs?
Discuss answers with class: • What will be the difference in
daily weight gain of theoffspring from each boar?
o Listen for: Offspring fromBoar A can be expectedto gain 0.5 pounds perday more than offspringof Boar B and 0.7 poundsper day more thanoffspring from Boar C.
o Offspring of Boar B canbe expected to gain 0.5pounds per day less thanoffspring from Boar A but0.2 per day more thanoffspring from Boar C.
• Which offspring is expected togrow the slowest?
o Listen for: Boar C. Theoffspring from Boar C areexpected to grow theslowest compared to
were 3.2 pounds heavier at 21 days than Sow B (when bred to the same boar).
EPD Example #1: EPD average daily gain - Boar A: 0.8 pounds, Boar B: 0.3 pounds, Boar C: 0.1 pounds.
LESSON SIX: How Do We Get Better Pigs?
offspring from Boars A and B.
o However, the offspringfrom Boar C are stillexpected to grow 0.1pounds per day fasterthan offspring of boars inthe general population.
Using the PowerPoint and Pork Pages (insert number), instruct students to take two minutes to review and answer the corresponding questions for EPD example #2.
Slide 148 in DPPI6 How Do We Get Better Pigs?
Discuss answers with class: • What will be the difference in
litter size of the daughtersfrom each sow?
o Listen for: Daughtersfrom Sow C can beexpected to have 0.3 and0.6 pigs per litter morethan daughters fromSows B and A,respectively.
o Daughters of Sow B areexpected to have 0.3more but 0.3 less thandaughters of Sows A andC, respectively.
• Which sow’s daughter isexpected to have the largestlitter size?
o Listen for: Sow C.Daughters of Sow A areexpected to have thesmallest litters compared
EPD Example #2: EPD litter size - Sow A: 0.0 pigs per litter, Sow B: 0.3 pigs per litter, Sow C: 0.6 pigs per litter.
LESSON SIX: How Do We Get Better Pigs?
to daughters of Sows B and C
Ask: How do you think EPDs have been used to show the changes identified in the pictures from the Interest Approach?
Ticket Out the Door: Then-Now-Future
Return to the Then-Now-Future chart either on the wall or the PowerPoint.
Instruct students to reflect back on this lesson using the following questions and to respond in the corresponding columns using one of the methods described above.
• In the “Then” column, respond to the following question:o Reflecting back on the photos from the interest approach and to pictures of pigs
seen throughout the last two days, how have pigs changed in the last 50 years? Listen/watch for: More lean muscle, better structure, increased skeletal
mass• In the “Future” column, respond to the following question:
o Knowing pig farmers will play a greater role in feeding more people with lessresources (land, water, and energy), what role will genetics play in porkproduction in the next 50 years? Why? What could that look like? Listen for: Selection for disease control, reproduction efficiencies, larger
average litter size
Slide 149 in DPPI6 How Do We Get Better Pigs?
Lesson Six – How Do We Get Better Pigs?
Glossary of Terms TERM DEFINITION
Rebreeding interval The period of time between when a litter is weaned from the sow and when that sow returns to estrus for breeding. Commonly referred to as the weaning to estrus interval.
Terminal crossbreeding program A breeding system which involves breeding pigs of two different breeds to obtain crossbred female offspring
who are then mated to males of a third breed to produce terminal crossbred pigs for market.
Feed efficiency Ratio of feed intake to weight gain
Terminal/Paternal sire Sires whose offspring are destined for market, i.e., not kept for breeding purposes
Marbled White flecks of intramuscular fat in cuts of meat. Impacts the tenderness, moistness, and overall flavor.
Rate of gain The rate of weight gain over a specific
period of time
Breeding systems the approach taken to pair a boar and a gilt or sow for breeding in order to incorporate or maintain desired traits.
Purebred breeding Mating two animals of the same breed in which a certain number of genetic lines are available
Crossbreeding Mating animals of different breeds
Heterosis (hybrid vigor) Tendency of a crossbred individual to show qualities superior to those of both parents
Genetics Science of the study of resemblances
and differences that exist among individuals
Trait Characteristics expressed by genes and/or influenced by environment; include physical and behavioral
Gene Characteristics expressed by genes and/or influenced by environment; include physical and behavioral
Genotype Internal hereditary information that contains genetic code
Phenotype Outwardly-expressed traits orcharacteristics
Dominant Shows its specific trait even if only one parent passed the gene to offspring
Recessive Shows specific trait only when bothparents pass the gene to offspring
Hereditary Passed or capable of being passed from
parent to offspring by means of genes
Expected Progeny Difference (EPD) How the animal’s offspring will perform compared to the offspring of another boar (sire) or sow (dam) within the same breed
Progeny Offspring
Additional Information • Additional facts about the Yorkshire breed:
o Pages 71▪ Long, clean neck and face
▪ Long, lean, well-shaped top▪ Most-recorded breed of swine in the U.S. and Canada▪ The goal of the Yorkshire breed is to be a source of durable
mother lines that can contribute to longevity and carcass merit.
• Additional facts about the Duroc breed:o Page 71
▪ Long, clean face and neck▪ Square, expressively-muscled top▪ Second-most recorded breed of swine in the U.S. and major
breed in other countries
▪ At the 1983 Chicago World Fair, Durocs gained wide popularity
at the first successful Duroc hog show.▪ The purebred Duroc is distinguished for breed potency in
today’s picture of swine improvement and holds forth invitingpromise of future usefulness and value.
• Additional facts about the Hampshire breed:o Page 72
▪ Wide forehead and good width between eyes▪ Long neck▪ Possibly the oldest, early-American breed of hogs in existence
today.▪ Their ability to sire winning carcasses is unequalled and they
continue to set the standard by which all other terminal siresare evaluated.
• Additional facts about the Landrace breed:▪ Long, clean neck and face▪ Wide-based from front to rear▪ It was mainly through the use of Landrace that Denmark became
the chief bacon-exporting country• To protect this position, Denmark refused to export
purebred Landrace breeding stock for many years.• Additional facts about the Berkshire breed:
▪ First swine registry established in the world – 1875▪ For years, the British Royal Family kept a large Berkshire herd at
Windsor Castle▪ More sensitive to their environment
• Additional facts about the Chester White breed:
▪ Chester Whites have kept their popularity with thousa nds of pork producers.
▪ Packers prefer Chester Whites because of their white skin and proven superior muscle quality
• Additional facts about the Poland China breed:▪ Leads U.S. pork production in pounds of hog per sow per year▪ Bred for two important requirements: size and ability to traveler
well.• As pigs have changed and evolved over the years, pig farmers use breeding
systems (mating systems) to specifically improve characteristics (many of which we visually see) including a pig’s abilit y to yield high-quality meat.
• Feed efficiency – future increased productivity of pigs is linked to efficiency, which means pig farmers need pigs with the built -in ability to convert feed into muscle even more efficiently and grow faster at the s ame time.
• Pig farmers who thoroughly understand genetics and utilize improved genetic evaluation techniques will be able to improve production efficiency and lower their production costs. This allows them to stay competitive in today’s changing pork industry.
Additional Resources American Berkshire (n.d.). Founded in 1875. Retrieved from
https://americanberkshire.com/history/
Certified Pedigree Swine (n.d.) Breeds | Chester White. Retrieved from
http://cpsswine.com/chester-white/
Certified Pedigree Swine (n.d.) Breeds | Poland China. Retrieved from http://cpsswine.com/poland-china/
Certified Pedigree Swine (n.d.) Breeds | Spotted. Retrieved from http://cpsswine.com/spotted/
National Swine Registry (n.d.). Ideal Duroc Features. Retrieved from https://nationalswine.com/resources/docs/education/ideal_flyers/duroc_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Hampshire Features. Retrieved from https://nationalswine.com/resources/docs/educat ion/ideal_flyers/hampshire_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Landrace Features. Retrieved from https://nationalswine.com/resources/docs/education/ideal_flyers/landrace_ideal_flyer.pdf
National Swine Registry (n.d.). Ideal Yorkshire Features. Retrieved from https://nationalswine.com/resources/docs/education/ideal_flyers/yorkshire_ideal_flyer.pdf
Real Pig Farming (2018, February 21). History of Pigs in America. Retrieved from https://realpigfarming.com/history-of-pigs-in-america-7c4e8b837228
AS6.1a – Breed Identification Cards
Print and cut out one set of these cards. Each group receives one breed card
YORKSHIRE
DUROC
AS6.1b – Breed Identification Cards
Print and cut out one set of these cards. Each group receives one breed card
HAMPSHIRE
LANDRACE
AS6.1c – Breed Identification Cards
Print and cut out one set of these cards. Each group receives one breed card
BERKSHIRE
SPOTTED
AS6.1d – Breed Identification Cards
Print and cut out one set of these cards. Each group receives one breed card
CHESTER WHITE
POLAND CHINA
AS6.2a – Genetics Matching Cards
Print and cut out a set of cards per group of three to four students.
GENETICS TRAIT
GENE GENOTYPE
PHENOTYPE DOMINANT
RECESSIVE HEREDITARY
AS6.2b – Genetics Matching Cards
Print and cut out a set of cards per group of three to four students.
Science of the study of resemblances and
differences that exist among individuals
Characteristics expressed by genes and/or influenced
by environment; include physical and behavioral
Part of DNA that carrieshereditary information passed from parents to
offspring
Internal hereditary information that
contains genetic code
Outwardly-expressed traits or
characteristics
Shows its specific trait even if only one parent
passed the gene to offspring
Shows specific trait only when bothparents pass the gene to offspring
Passed or capable of being passed from
parent to offspring by means of genes
AS6.3 – Pigs and Genetics Statements
Print and cut out each statement. Students will be divided into three groups and each group will receive one of the statements.
GROUP 1: As pigs have changed and evolved over the years, pig
farmers use breeding systems (mating systems) to specifically improve characteristics (many of which we
visually see) including a pig’s ability to yield high-quality meat.
GROUP 2: Feed efficiency – future increased productivity of pigs is linked to efficiency, which means pig farmers need
pigs with the built-in ability to convert feed into muscle even more efficiently and grow faster at the
same time.
GROUP 3: Pig farmers who thoroughly understand genetics and
utilize improved genetic evaluation techniques will be able to improve production efficiency and lower their production costs. This allows them to stay competitive
in today’s changing pork industry.
AS6.4 – EPDs
Print a copy of this worksheet for each student. This is an optional activity.
EPD Example #1: EPD average daily gain - Boar A: 0.8 pounds, Boar B: 0.3 pounds, Boar C: 0.1 pounds.
Answer the following questions: 1. What will be the difference in daily weight gain of the offspring from
each boar?
2. Which offspring is expected to grow the slowest?
EPD Example #2: EPD litter size - Sow A: 0.0 pigs per litter, Sow B: 0.3 pigs per litter, Sow C: 0.6 pigs per litter.
Answer the following questions: 1. What will be the difference in litter size of the daughters from each sow?
2. Which sow’s daughter is expected to have the largest litter size?
PORK PAGES: Lesson Six
Breeds of Pigs Pork Page 6.1
Better as it relates to the pork industry:
Yorkshire Duroc
Hampshire Landrace
PORK PAGES: Lesson Six
Breeding Systems Pork Page 6.2
These _________________ breeds, and all other pig breeds, emerged because there was (and is) a need for __________, or more _________________________, pigs.
Improvement of pigs is based on the __________________ farmers __________________. Improving a ________________________ based on _______________________________. Examples include:
• _____________________________________________
• _____________________________________________
• _____________________________________________
There are ____________________________ that help pig farmers get _______________________________ in pigs produced.
Breeding systems (aka, _____________________________): Breeding or mating systems are the approach taken to pair a ______________ and a ______________or ___________for breeding in order to incorporate or maintain ______________________.
Because the ___________________ of a pig plays an important role in its _______________________ and ____________________________, all _______________________________ should be familiar with breeding systems for pigs.
Types of Mating Purebred breeding:
• Mating two animals of the ____________________ in which a certain number of_______________________________ are available.
• This results in ______________ of a specific breed__________________________________________________________
• Reasons someone would choose purebred breeding:o ____________________________________________________________
o ____________________________________________________________
o ____________________________________________________________
PORK PAGES: Lesson Six
• Mating animals of _______________________________________• Crossbreeding animals with ________________________ is an attempt to maximize
_____________________, the ability of the offspring to___________________________________________.
• Results in _____________________________, ______________, and/or________________
• Reasons someone would choose crossbreeding:o ____________________________________________________________o ____________________________________________________________o ____________________________________________________________o ____________________________________________________________
Breeding Systems and Genetics
• ________________ and ________________ are how producers improve productiontraits in pigs.
• Advances in ________________ goes hand-in-hand with ____________________.• This impacts the _________________________________.
Genetics Definitions
• Genetics:
• Trait:
• Gene:
• Genotype:
• Phenotype:
• Dominant:
• Recessive:
• Hereditary:
Crossbreeding:
Breeds of Pigs Pork Page 6.1
PORK PAGES: Lesson Six
• Genetics involves _______________________ and _______________________. A genotype is the ________________________ for the phenotype __________________________________.
o Example of a phenotype: ____________________________________• ____________ _____ can be ________________________________ or
______________________________.
o Example:
Expected Progeny Differences (EPDs)
• A tool used to help pig farmers identify genetic traits to improve their herd is__________________________________________________
• EPD definition:_________________________________________________________________________________________________________________________________
• Using EPDs, producers can select __________________ and _________________ thatwill produce pigs with the production _______________________________ desired to
make improvements to the ____________________________________.
• Areas that EPDs include are: ____________________________________________
______________________________________________________________________
• EPDs are good measurements of _______________________ because they are adjusted
for the different amounts of information available for each animal
______________________________________________________________________
• EPD Example:o EPD litter weaning weight:
Sow A: _________ pounds.
Sow B: ______ pounds.
This means __________ daughters would likely have litter weights that
were _______________________ at 21 days than _____________ (when
bred to the same boar).
Genetics
Breeds of Pigs Pork Page 6.1