understanding genetics for use in goat production

Understanding GeneticsUnderstanding Genetics For Use InFor Use In Goat ProductionGoat Production

Dr. Dennis OnksDr. Dennis OnksDirectorDirectorMiddle TN Research CenterMiddle TN Research CenterUniversity of TennesseeUniversity of Tennessee

PHENOTYPEPHENOTYPE

AN ANIMAL’S VISUAL EXPRESSION ORAN ANIMAL’S VISUAL EXPRESSION ORPERFORMANCE IN ANY TRAITPERFORMANCE IN ANY TRAIT

The Phenotype is the outcome of The Phenotype is the outcome of Genetic Transfer as developed Genetic Transfer as developed in a production Environmentin a production Environment

PHENOTYPEPHENOTYPE

Defined as the sum of the genetic Defined as the sum of the genetic and environmental variationand environmental variation

The Genetic variation accounts for 25% ofThe Genetic variation accounts for 25% ofThe Phenotype while the Environment The Phenotype while the Environment Accounts for Accounts for 75%!75%!

Sound Breeding ProgramSound Breeding Program

Maximum Genetic Improvement occurs Maximum Genetic Improvement occurs In a Herd Environment that allows theIn a Herd Environment that allows theImproved Genetics to be Improved Genetics to be ExpressedExpressed

Sources of Sources of Environmental VariationEnvironmental Variation

1.1. WeatherWeather2.2. Land TopographyLand Topography3.3. Structural ResourcesStructural Resources4.4. Forages and FeedingForages and Feeding5.5. Health and SanitationHealth and Sanitation

How Traits are InheritedHow Traits are Inherited

Genetic Variation is the study ofGenetic Variation is the study of

•All body cells contain “Blueprints” with All body cells contain “Blueprints” with instructions as to how an animal will look or instructions as to how an animal will look or act etc.act etc.

•DNA or Deoxyribonucleic Acid contains the DNA or Deoxyribonucleic Acid contains the genes of traits in the double helix ribbons genes of traits in the double helix ribbons located in every celllocated in every cell

GENEGENE

The combination of genes are attached to The combination of genes are attached to chromosomes which guide the animal to expresschromosomes which guide the animal to expressA trait or responseA trait or response

http://library.thinkquest.orghttp://library.thinkquest.org

Species differ in chromosomesSpecies differ in chromosomes

Humans Humans 23 pairs of chromosomes23 pairs of chromosomes

Cattle Cattle 30 pairs of chromosomes30 pairs of chromosomes

SheepSheep 27 pairs of chromosomes27 pairs of chromosomes

SwineSwine 19 pairs of chromosomes19 pairs of chromosomes

Chicken Chicken 39 pairs of chromosomes39 pairs of chromosomes

GoatGoat 30 pairs of chromosomes30 pairs of chromosomes

HorseHorse 16 pairs of chromosomes16 pairs of chromosomes

How Traits are InheritedHow Traits are InheritedThe science of ½’s since each living animal receives a The science of ½’s since each living animal receives a Sample ½ of its genetics from its father and a sample ½Sample ½ of its genetics from its father and a sample ½ of its genetics from its mother.of its genetics from its mother.The process of halving is done by MeiosisThe process of halving is done by Meiosis

Gene DominanceGene Dominance

One Gene One Gene overshadows overshadows The expression of its The expression of its other pair (alleleother pair (allele)

WW and WW and Ww Ww = White = White

We’re heterozygousWe’re heterozygous (different)(different)

Recessive GenesRecessive Genes•The gene that is The gene that is overshadowed by a overshadowed by a dominant gene. dominant gene. Recessive genes can only Recessive genes can only be expressed when they be expressed when they both are presentboth are present

RED COAT COLOR = wwRED COAT COLOR = ww

We’re HomozygousWe’re Homozygous(the same)(the same)

QUALITATIVE QUALITATIVE TRAITSTRAITS

TRAITS THAT ARE AFFECTEDTRAITS THAT ARE AFFECTEDBY A SINGLE OR A FEWBY A SINGLE OR A FEWPAIR OF GENESPAIR OF GENES

COAT COLORCOAT COLORTEETHTEETHHORNSHORNS

QUANTITATIVE TRAITSQUANTITATIVE TRAITS

TRAITS AFFECTED BY NUMEROUSTRAITS AFFECTED BY NUMEROUS PAIRS OF GENESPAIRS OF GENES

The thousands of genes present makeThe thousands of genes present makecountless combinations possible in ancountless combinations possible in ananimal. Since genes are too small toanimal. Since genes are too small toidentify individually, they express theiridentify individually, they express theirpresence by such outward effects aspresence by such outward effects asdifferences in growth, carcass or differences in growth, carcass or

reproduction traitsreproduction traits

Quantitative Traits (cont’d)Quantitative Traits (cont’d)Growth traitsGrowth traits

Birth weightBirth weightWeaning weightWeaning weightYearling weightYearling weightGrowth rate (ADG)Growth rate (ADG)Frame sizeFrame size

Carcass traitsCarcass traitsRib eye areaRib eye areaFat thicknessFat thicknessMarblingMarbling

Reproduction traitsReproduction traitsfertility/adaptabilityfertility/adaptability

Is the buck on the left bigger because he had Is the buck on the left bigger because he had better genetics for growth or because he was better genetics for growth or because he was provided a better environment?provided a better environment?

Which buck has the best genetics for growth?Which buck has the best genetics for growth?

IMPROVEMENT OF ANY IMPROVEMENT OF ANY TRAIT DEPENDS:TRAIT DEPENDS:

MEASURING DIFFERENCES IN A TRAITMEASURING DIFFERENCES IN A TRAIT

ACCURATELY IDENTIFYING SUPERIORACCURATELY IDENTIFYING SUPERIORINDIVIDUALS IN THE TRAITINDIVIDUALS IN THE TRAIT

USING SUPERIOR INDIVIDUALS AS PARENTSUSING SUPERIOR INDIVIDUALS AS PARENTS

HOW HERITABLE THE TRAIT IS (heritability)HOW HERITABLE THE TRAIT IS (heritability)

What is Selection?What is Selection?• Choosing animals to be parents for the next Choosing animals to be parents for the next

generation to produce certain characteristicsgeneration to produce certain characteristics• Low Birth weightLow Birth weight• Heavier Weaning WeightHeavier Weaning Weight• Gaining FastGaining Fast• Horned or PolledHorned or Polled• TemperamentTemperament• Better Eating QualityBetter Eating Quality

Heritability(hHeritability(h22))

ReproductionReproductionfertilityfertility,etc.,etc.

ReproductionReproductionfertilityfertility,etc.,etc.

ProductionProductiongrowthgrowth

ProductionProductiongrowthgrowth

ProductProductcarcasscarcass

ProductProductcarcasscarcass

LowLowLowLow

ModerateModerateModerateModerate

HighHighHighHigh

((Heritability is a measure of how a trait will Heritability is a measure of how a trait will respond to selectionrespond to selection))

Percentage of the differences (measured or observed) in a trait Percentage of the differences (measured or observed) in a trait between animals that are transmitted to the offspring.between animals that are transmitted to the offspring.

Low Heritable Traits

• Birth Interval 5-10%

• Number Born 15%

• Rear Legs 15%

• Udder Support 20%

• Reproduction 15%

Moderately Heritable Traits

• Birth Weight 30-40%

• Weaning Weight 20-30%

• Yearling Weight 40%

• Feed Conversion 40%

• Quality Grade 40%

• Ribeye Area 40-45%

• Muscling 40-45%

Highly Heritable Traits

• Mature Weight 65%

• Milk Fat 55%

• Stature, Frame 45-50%

• Carcass Weight 45-50%

• Scrotal Circumference 50%

Selection for traits is ImpactedSelection for traits is Impactedby the by the Correlation(rCorrelation(r22))

Between TraitsBetween Traits

• Genetic Correlation measures the genetic association between traits

• Phenotypic Correlation measures the local or environmental association between traits

• Correlation ranges in value of +1.0 to –1.0 (indicates the direction of association)

Phenotypic CorrelationsBodyWT Length Heart Girth Backfat Loin Area

Length

Heart Girth

Backfat

Loin Area

ScrotalCircumference

KiddingDifficulty -.50

+.92

+.97 +.87

+.60 +.45 +.51

+.90 +.74 +.89 +.79

+.86 +.87 +.77 +.51 +.67

Use of Heritability andCorrelations

• Selection for Weight makes moderate progress (h2=40-65%)

• Positive Correlation (r2=+.50) between birth, weaning and carcass traits means Selection will result in increases in all three traits.

Use of Heritability andCorrelations

• Selection for Weight makes moderate progress (h2=40-65%)

• Negative Correlation (r2=-.50) between Weight and Kidding Difficulty means Selection will result with increased Kidding Difficulty and birth, weaning and carcass weight.

• ConsumerConsumer• PackerPacker• FeederFeeder• Commercial producerCommercial producer• Purebred BreederPurebred Breeder

• Each section may have differing Each section may have differing trait criteriatrait criteria

Selection for the IndustrySelection for the Industry

CONSUMERCONSUMER

• Price/ ValuePrice/ Value

• ConsistencyConsistency

• HolidaysHolidays

• Taste/ FlavorTaste/ Flavor

• Safety/ HealthSafety/ Health

PACKERPACKER• Dressing PercentDressing Percent

• Quality GradeQuality Grade

• Yield GradeYield Grade

FEEDERFEEDER• HealthHealth

• GainGain

• Feed EfficiencyFeed Efficiency

Commercial or Purebred Commercial or Purebred ProducerProducer

• ReproductionReproduction

• Maintenance CostMaintenance Cost

• GrowthGrowth– WeaningWeaning

– YearlingYearling

ECONOMIC ECONOMIC IMPORTANCEIMPORTANCE

TRAITTRAIT

RELATIVERELATIVE

IMPORTANCEIMPORTANCE

REPRODUCTIONREPRODUCTION 22

PRODUCTIONPRODUCTION 11

PRODUCTPRODUCT 11

HeritabilityHeritability

ReproductionReproductionReproductionReproduction

ProductionProductionProductionProduction

ProductProductProductProduct

LowLowLowLow

ModerateModerateModerateModerate

HighHighHighHigh

(Heritability is a measure of how a trait will (Heritability is a measure of how a trait will respond to selection)respond to selection)

““or how well the offspring resemble their parents phenotype”or how well the offspring resemble their parents phenotype”

MEASURABLE TRAITMEASURABLE TRAIT (Phenotype) (Phenotype)

• GENETIC EFFECTSGENETIC EFFECTS– ½ GENETICS FROM BUCK½ GENETICS FROM BUCK– ½ GENETICS FROM DOE½ GENETICS FROM DOE

• ENVIRONMENTAL EFFECTSENVIRONMENTAL EFFECTS– WEATHERWEATHER– NUTRITIONNUTRITION– HEALTHHEALTH– Etc.Etc.

Measures of PhenotypeMeasures of Phenotype

P = G + EP = G + E

Birth weightsWeaning weightsYearling weightsCarcass TraitsReproductive traitsAdaptability

Measures of PhenotypeMeasures of Phenotype

P = G + EP = G + ERequires: 1. Identification of animals

2. Equipment to record trait measure3. Record Keeping System4. Computer with Spreadsheet is economical and recommended

Genetic EvaluationsGenetic Evaluations

Phenotypes and PedigreesPhenotypes and Pedigrees

Objective: convert data into genetic Objective: convert data into genetic information for the purpose of selectioninformation for the purpose of selection

Separate genetic portion of phenotype fromSeparate genetic portion of phenotype from environment. environment.

• 90 DAYS OLD90 DAYS OLD• ON FARM “A”ON FARM “A”• BUCKBUCK• 2 YR DOE2 YR DOE

• 105 DAYS OLD105 DAYS OLD• ON FARM “A”ON FARM “A”• BUCKBUCK• 4 YR DOE4 YR DOE

WHAT ARE THE WHAT ARE THE KNOWNKNOWN ENVIRONMENTAL EFFECTS? ENVIRONMENTAL EFFECTS?

41 lbs38 lbs

AGEAGE- 15 DAYS15 DAYS + 15 DAYS+ 15 DAYS

AGE OF DOEAGE OF DOE

2 YR OLD2 YR OLD 4 YEAR 4 YEAR OLDOLD

FARMFARM

SAMESAME SAMESAME

Known Environmental EffectsKnown Environmental Effects

680680 650650

Adjusted 90 day wt.Adjusted 90 day wt.formulaformula

(Actual Wt - Birth wt)(Actual Wt - Birth wt)

Age in daysAge in daysXX 90 90 + doe age adj. + birth wt + doe age adj. + birth wt

Breed associations are calculating adjustments as they accumulate data from the breeders

Adjusted 90 day wt.Adjusted 90 day wt.

(41 –8)(41 –8) 90 days90 days X 90 + 5 + 8X 90 + 5 + 8

(42 – 7)(42 – 7)105 days105 days

X 90 + 0 + 7X 90 + 0 + 7

= 45.999 Lbs.= 45.999 Lbs. = 36.999 Lbs= 36.999 Lbs..

Contemporary Group RatiosContemporary Group Ratios

adj. 90 day wtadj. 90 day wt adj. 90 day wtadj. 90 day wt

Herd Avg. = 36Herd Avg. = 36 Herd Avg.= 36Herd Avg.= 36

Ratio = 39/36Ratio = 39/36 Ratio = 37/36Ratio = 37/36

108108 102.8102.8

3939 3737

Useful for Useful for withinwithin herd selections but not between herds herd selections but not between herds

Buck A Buck B

We We mustmust expect differences between expect differences between animals across different environmentsanimals across different environments

Future Genetic EvaluationsFuture Genetic Evaluations

Source of dataSource of data

AncestorsAncestors

Collateral relativesCollateral relatives

DescendentsDescendents

Own performanceOwn performance

Correlated traitsCorrelated traits

(EPD)-Expected Progeny(EPD)-Expected ProgenyDifferenceDifference

• A prediction of the genetics a goat will pass on to his kids, when compared to other goats within the breed

• Takes into account the actual measurements, all ancestral measurements and environment

• Not a perfect science, so use as a risk management tool

College Football BCSCollege Football BCS

Purpose is to identify best college football teamsPurpose is to identify best college football teams

Source of DataSource of Data :

AP rankingAP rankingUSA RankingUSA RankingRecordRecordStrength of scheduleStrength of scheduleetc.etc.

Ranking changes as more games are playedRanking changes as more games are played

National Goat EvaluationNational Goat EvaluationBreed SpecificBreed Specific

Breed summaries reportBreed summaries report

EPDsEPDs.

Expected Progeny DifferenceExpected Progeny DifferenceAnd Breeding ValuesAnd Breeding Values

The American Boer Goat Association, American Dairy Goat Association, National DHI Program

Interpreting EPDsInterpreting EPDsProvide a prediction of future progeny performance of Provide a prediction of future progeny performance of one individual compared to future progeny of one individual compared to future progeny of another individual within a breed for a specific trait.another individual within a breed for a specific trait.

Allow one to compare or rank the genetic superiorityAllow one to compare or rank the genetic superiorityof individual animals within a breed for a specificof individual animals within a breed for a specificTrait.Trait.

EPDs are reported in the actual unit that the trait is EPDs are reported in the actual unit that the trait is Measured (Lbs. for growth traits).Measured (Lbs. for growth traits).

They can be positive or negative numbersThey can be positive or negative numbers

Effective EPDs: Examples

• Scrotal Circumference (SC)High SC bucks sire does with earlier Puberty• Birth Weight (BW)Low BW bucks have more live kids• Average Daily Gain (ADG)Allows choice for replacements or sale of

weanlings• Carcass Merit (CM)Allows choice for direct or wholesale Marketing

Array of genetic value of an individualArray of genetic value of an individual

(EPD), adjusted trait performance(EPD), adjusted trait performance

AvgAvg.

Difference in Array for two BucksDifference in Array for two BucksFull Brothers have a sample 1/2 genetics of buck & of the doe butFull Brothers have a sample 1/2 genetics of buck & of the doe butNot necessarily the exact same geneticsNot necessarily the exact same genetics

HOW ABOUTa

BREAK?

How do you use genetic tools in a selection program ?

Start by using available informationStart by using available information

Evaluate Goat Breed Characteristics thatEvaluate Goat Breed Characteristics thatAppear to fit your marketing planAppear to fit your marketing plan

Average Breeding Values of SixDairy Goat Breeds

Breed Milk Fat Protein

Alpine 0 0.0 0.0

LaMancha -114 -0.7 -1.3

Nubian -531 4.4 -1.9

Oberhasli -476 -15.7 -14.3

Saanen 60 0.8 1.9

Toggenburg -18 -6.4 -.35

Alpine LaMancha Nubian

You would expect 114 and 531 pounds less milkFrom LaMancha and Nubian as compared to Alpine

Oberhasli Saanen Toggenburg

When compared to Alpine, you would expect 60 lbs moreMilk for Saanen, 476 lbs less milk from Oberhasli and 18 lbs less milk from Toggenburg

Infant Meat Goat Industry

• Breed Associations are growing

• Members are sending data through membership

• Information is increasing

• Most selections must come from individual and herd data

Infant Meat Goat Industry

• Majority of information reports data on Spanish (brush), Boer, Kiko, San Clemente, Myotonic (fainting) and crossbreds

• This data provides ranges for comparison

• Emerging breed associations will help supply needed breeding values

CommonMeatGoatBreeds

KIKO Spanish

BOERSan Clemente

Boer Buck Performance Test(Langston Univ. & Okla. State Univ., 2004)

Total Gain (lbs) 53.1 27.5-68.2

Average Daily Gain (lbs per day)

0.63 0.33-0.81

Feed Efficiency (lbs of feed per lb of gain)

6.8 5.1-9.3

Loin eye area

(square inches)1.95 1.29-2.54

Growth Performance(Langston Univ., 2003)

DM intake (lb/day)

Avg Daily Gain (lb)

Feed Efficiency (adg/dm feed)

Alpine 1.56 0.13 0.339

Angora 1.05 0.13 0.61

Boer 1.53 0.19 0.559

Spanish 1.13 0.08 0.32

Carcass Performance(Texas A&M Univ, 1999)

Feedlot Range Feedlot Range

Live Wt 83.97 45.12 73.74 40.52

Carcass Wt

47.78 22.0 42.33 19.25

Back Fat .047 .012 .028 .012

Type 11.42 3.25 8.33 1.83

Marbling 3.35 1.70 3.06 1.80

Common FibreGoat Breeds

Angora

Cashmere

Mohair Production & ValueYear Goats

Clipped

(1000 hd)

Production

(1000 lbs)

Price per Unit

(US $)

Value of Production

(1000 $)

2003 283 2,174 1.58 3,435

2002 283 2,174 1.58 3,432

2001 402 2,628 4.00 10,609

2000 444 2,896 3.00 10,016

1999 700 5,045 2.00 12,562

1998 931 6,814 2.00 15,341

Putting it Together at this Point

• Develop Marketing Plan

• Use Breed Characteristics

• Evaluate Breeding Values

• Gather herd performance data

• Compare Animal Performance

• Develop Record System

Genetic Selection orGenetic Selection orBreeding PlansBreeding Plans

Interpreting AdjustedInterpreting Adjusted

Performance TraitsPerformance Traits

These tools predict the average value of These tools predict the average value of genetic ability offered by an animal.genetic ability offered by an animal.

Available Breeding Tools

• First: Pedigree Evaluations

• Second: Use of Heterosis

• Third: Trait Calculation & Indexes

KidKid87 ½ %87 ½ %

Buck 1 (50%)Buck 1 (50%)

Buck 2 (25%)Buck 2 (25%)

Buck 3 (12.5%)Buck 3 (12.5%)Doe 1 by buck 2Doe 1 by buck 2

Doe 2 by buck 3Doe 2 by buck 3

FIRSTFIRST87 ½ % of genetics of kid crop 87 ½ % of genetics of kid crop is a result of last 3 bucks used!!is a result of last 3 bucks used!!

KIDKID

Buck (1/2 Trait Buck (1/2 Trait Value )Value )

MG Buck (1/4 Trait MG Buck (1/4 Trait Value)Value)

DoeDoe

FIRSTFIRSTCalculating Pedigree Estimate Calculating Pedigree Estimate

EPDsEPDs

Pedigree Est. = ½ Buck Value + ¼ MGB ValuePedigree Est. = ½ Buck Value + ¼ MGB Value

KIDKID

Toots (birth value=6.4)Toots (birth value=6.4)

Caesar (birth value=8.8)Caesar (birth value=8.8)

DoeDoe

FIRSTFIRSTCalculating Pedigree Estimate Calculating Pedigree Estimate

EPDsEPDs

Pedigree Est. Birth value= ½ (6.4)+ ¼ (8.8)= 5.4Pedigree Est. Birth value= ½ (6.4)+ ¼ (8.8)= 5.4

Optimizing breed complementarityOptimizing breed complementarity

Capitalizing Heterosis (Hybrid Vigor)Capitalizing Heterosis (Hybrid Vigor)

SECONDSECONDBenefits of CrossbreedingBenefits of Crossbreeding

HETEROSIS (HYBRID VIGORHETEROSIS (HYBRID VIGOR))

Measure of superior performance of a Measure of superior performance of a trait of the ‘Crossbred individual’ overtrait of the ‘Crossbred individual’ overand above the average performanceand above the average performanceof that trait of the two parental breedsof that trait of the two parental breeds.

% HETEROSIS% HETEROSIS

Crossbred Avg. Crossbred Avg. –– Parental Breeds AvgParental Breeds Avg. X 100. X 100

Parental Breeds AvgParental Breeds Avg.

HeterosisHeterosis

Breed ABreed A

F1 CrossF1 Cross

Breed BBreed B

ReproductionReproduction

Growth

Carcass

Cross Bred Boer-Spanish

Example of % heterosis:Example of % heterosis:

Breed Breed AA avg. weaning weight = 45 Lbs.avg. weaning weight = 45 Lbs.

Breed Breed BB avg. weaning weight = 51 Lbsavg. weaning weight = 51 Lbs.

AABB crossbred avg. weaning weight = 50crossbred avg. weaning weight = 50

% Heterosis =% Heterosis = 5050–– 4848 X 100 = 4%X 100 = 4%4848

Response to HeterosisResponse to Heterosis

Inversely related to the heritability of the traitInversely related to the heritability of the trait

The The More diverseMore diverse differences of breeds useddifferences of breeds used

The The greatergreater the responsethe response

Types of HeterosisTypes of Heterosis

IndividualIndividual --expressed in the XB kidexpressed in the XB kid

MaternalMaternal --expressed in the doeexpressed in the doe

PaternalPaternal --expressed in the buckexpressed in the buck

Expected % Heterosis Expected % Heterosis

4.24.24.74.7Wean Wt.Wean Wt.

14.814.88.58.5Lbs. kid/doeLbs. kid/doe

1.61.62.72.7Birth wt.Birth wt.

2.02.01.71.7AdaptabilityAdaptability

6.66.63.43.4Kidding %Kidding %

MaternalMaternalIndividualIndividualTraitTrait

% of Maximum Heterosis% of Maximum Heterosisrealized in different crossbred realized in different crossbred

percentagespercentages

25257/8 : 1/87/8 : 1/8

37.537.53/16 : 13/163/16 : 13/16

505075 : 2575 : 25

62.562.55/16 : 11/165/16 : 11/16

75753/8 : 5/83/8 : 5/8

87.587.59/16 : 7/169/16 : 7/16

10010050 : 25 : 2550 : 25 : 25

10010050: 5050: 50

% Max. Heterosis% Max. HeterosisCrossbred %Crossbred %

SECONDSECONDCrossbreeding SystemsCrossbreeding Systems

To improve:To improve:

1.1. Lbs. Calf weaned per cow maintainedLbs. Calf weaned per cow maintained2.2. AdaptabilityAdaptability3.3. Live BirthsLive Births3.3. Other Traits of InterestOther Traits of Interest

11

A B

AB

Basic Two Way CrossBasic Two Way Cross

+ 8.5% Lbs. Kid/Doe+ 8.5% Lbs. Kid/Doe

Only capture Individual Heterosis in the KidOnly capture Individual Heterosis in the Kid

10

AA BB

3 Breed2 Breed

CC

AA BB

Heterosis increaseslbs. kid per doe

15%

Heterosis increaseslbs. kid per doe

20%

Rotational CrossbreedingRotational Crossbreeding

11

A B

T

RotationalRotational--Terminal Sire CrossbreedingTerminal Sire Crossbreeding

+23.3 % Lbs. kid/doe+23.3 % Lbs. kid/doe

Heterosis in different Heterosis in different crossbreeding systemscrossbreeding systems

% Heterosis in XB Population% Heterosis in XB Population

SystemSystem DoesDoes KidsKids lbs kidlbs kidwn/doewn/doe

Two breedTwo breed 00 100100 8.58.52 breed crisscross 672 breed crisscross 67 6767 15.615.63 breed rotation3 breed rotation 8686 8686 20.020.03 brd cross terminal 1003 brd cross terminal 100 100100 23.323.3BackcrossBackcross 100100 5050 19.019.0

% H e t e r o s i s f o r L b s . W e a n /D o e% H e t e r o s i s f o r L b s . W e a n /D o e

0

5

1 0

1 5

2 0

2 5

% H

eter

osis

I n d . H e t . M a t e r . H e t . I n d + M a t e r

I n d + M a te rM a t e r . H e t .I n d . H e t .

M a t e r n a l & I n d iv id u a l H e t e r o s is i s M a t e r n a l & I n d iv id u a l H e t e r o s is i s a d d i t iv ea d d it iv e

100DifferentBreeds of

GoatsWorldwide

4,950 4,950 CombinationsCombinations

• Two Breed Crosses with 100 different Two Breed Crosses with 100 different BreedsBreeds

161,200161,200CombinationsCombinations

•• Three Breed Crosses with 100 Different Three Breed Crosses with 100 Different BreedsBreeds

Use Genetic Tools and Breeding Values or

EPDsWhen Available

Identify bucks that will contribute toImprovement in economically important traits

PERFORMANCEPERFORMANCE

BENCHMARKSBENCHMARKS

What is the current level

of herd performance?

What direction (if any) should

the herd move?

Single Most Important Trait Single Most Important Trait In The Goat Industry ??In The Goat Industry ??

REPRODUCTION

THIRDMeasure of Production/

Reproduction

Lbs kid weaned / doe exposed= % kid crop weaned X avg. wn. Wt.

Prorates total lbs. kid weaned across all does maintainedProrates total lbs. kid weaned across all does maintained

Best measure of productivity

THIRDTHIRDLbs. Kid Weaned / Lbs. Kid Weaned /

Doe Doe ExposedExposed

% kid crop% kid crop Avg. W.WAvg. W.W. Lbs. / doeLbs. / doe

120120 3939 46.846.8

105 3939 40.940.9

9595 39 39 37.1 37.1

8585 39 39 33.2 33.2

Where Can I Find Where Can I Find Quality Data ?Quality Data ?

Individual herd OwnersIndividual herd Owners

Breed AssociationsBreed Associations

National Dairy ProgramNational Dairy Program

Establish Benchmark of Establish Benchmark of ProductionProduction

Determine which traits need improvementDetermine which traits need improvement

Select for that trait(s)Select for that trait(s)

BW= birth weightBW= birth weightWW= weaning weightWW= weaning weightSC= scrotal circumferenceSC= scrotal circumferenceAdaptabilityAdaptability

Identify How to Use DifferentBucks for Different Purposes

Produce Replacement Does

Terminal Cross Bucks

Kidding Ease Bucks

Carcass Merit Bucks

Remember

Genetic Correlations

(Antagonisms)Milk production, Growth rate (size)

vs. Fertility

vs. Maintenance requirements

Quality vs. Red Meat Yield

Growth rate and Calving ease

Birth weight vs. Yearling weight

Use Trait Qualities

Heritability Heterosis

Reproduction LOW HIGH(fertility)

Production MODERATE MODERATE(growth)

Product HIGH LOW(carcass)

-1.1 22 18 43 .48-1.1 22 18 43 .48

AA BB

CC DD

Which is the “BEST Buck”?Which is the “BEST Buck”?

5. 7 47 11 90 .095. 7 47 11 90 .09-1.1 22 18 43 .48-1.1 22 18 43 .48

Breed Avg. 11.5 42 33 150 Breed Avg. 11.5 42 33 150

AA BB

CC DD

Brth Ww SC M Brth Ww SC M

Pick Your BuckPick Your Buck

B=10, W=35, S=39, M=130

B=12, W=42, S=40, M=155

B=11, W=38, S=33, M=160B=15, W=45, S=41, M=170

GOOD BUCK?

Don’t Buy a “Billy in a Cart” USEA Source of Quality Information

Preliminary Selection onPerformance

Then FOCUS on:

-Structural Soundness

-Temperament

-Scrotal Circumference

-ect

STRUCTURAL SOUNDNESS

Skeletal design & how well the bonessupport the animal’s body

Related to Longevity

And Adaptability

FEET

LEGS

Correct Structures

Angle of Pastern is usually the same as Angle of Shoulder

Breeding Systems

Develop your Marketing Plan

Choose your breeds: Breeding Values and Characteristics

In a crossbreeding system, balance the characteristics of the breeds used.

Choose Bucks with performance data. Use EPDs when available.

•Systematic crossbreeding has benefits.

–Heterosis; Complementarity

•Planning is critical.

–Use EPDs when available.

•Crossbreeding is NOT a substitute for poor management.

Crossbreeding Considerations

Action PlanAction PlanSelection Selection Considerations

Use Breeding Values as a selection tool when available.

Target kidding difficulty, growth and doe size genetics to match environment.

Know your market ---Know your market --- what your herd will “produce”

Adopt a “consumer-focused”“consumer-focused” mindset towards carcass merit (avoid misfits).

Characterize strengths and weaknesses.

Consumers Consumers will shape will shape our future our future and set the and set the

Pace!Pace!