Designing Genetics and Selection for Seedstock
Breeders, Commercial Cattlemen and Show Ring Enthusiasts
ASA Fall Focus 2015: Confidence Builds Success
Scott P. Greiner, Ph.D.Extension Animal Scientist
Virginia [email protected] 540-231-9159
Putting Genetics to Work
What are your herd goals?
How fast can you get there?
What do you focus on?
Seedstock
Cow-Calf
Processor
Feeder
Consumer
Genetic Improvement∆G
Rate of genetic change influenced by:• Accuracy of selection• Selection intensity• Generation interval
Accuracy and Possible Change
BWEPD
BIFAccurac
y
PossibleChange
“true” EPD
RangeSire A +1.0 0.25 ±2.0 -1.0 to
+3.0Sire B +1.0 0.90 ±0.3 +0.7 to
+1.3
Magnitude of Selection
Simm
CE EPD
WW EPD
MB EPD
top 20% +11.6 +70 +0.26
bottom 20% +5.8 +55 +0.00
Difference 5.8 % 15 lb. 26 MS
Simm Hybrid
CE EPD
WW EPD
MB EPD
top 20% +13.7 +68 +0.51
bottom 20% +7.1 +51 +0.13
Difference 6.6 % 17 lb. 38 MS
Genetic Progress in Multiple Traits
Application of well-designed crossbreeding system• Heterosis• Breed Complementarity
Effective use of EPDs• Within Breeds• Across Breeds
AssumptionsMaximum profitability in cow-calf
sector is associated with crossbreeding (primarily through maternal heterosis)
Angus, Red Angus, and Hereford are the British breeds of choice and compose primary base of US cow herd
Continental x British crosses are most desirable for optimizing goals of cow-calf, feeder, packer, and consumer
Breed Average EPDs: Across Breed Basis
BW WW YW Milk MB REA FT
Angus +1.4 +50 +88 +23 +0.46 +0.41 +0.01
Red Angus +1.8 +30 +56 +21 +0.09 +0.11 -0.02
Hereford +5.9 +45 +52 +2 -0.26 +0.22 -0.05
Simmental +5.5 +58 +82 +25 -0.25 +1.20 -0.19
Simm Hybrid
+4.3 +55 +82 +25 -0.06 +1.02 -0.17
Simmental among Continental breeds:Higher CE, maternal CE, WW, YW, QG, and feed efficiency
0
-25
25
100
75
50
Diff = 61 lb
Diff = 38 lbDiff = 0.4 lb
Angus Simmental
Kuehn, US MARC
Major Breed Differences Today
Continental vs. British breeds Continental breeds have dramatically reduced birth
weights and improved calving ease over last 30 +years
Angus and Red Angus sire lightest BW calves with most calving ease
Daughters of Continental and British breeds similar in reproduction, calving ease, calf survival and similar in mature size
Breed differences in weaning weight and milk much smaller than 30+ years ago
British and Continental sired progeny do not differ significantly in postweaning growth or efficiency of live weight gain
Large differences exist between British and Continental breeds for carcass traits
Sire breed least squares means for height, condition score, and Sire breed least squares means for height, condition score, and weight of Fweight of F11 cows (adjusted for condition score) at 4 years of age cows (adjusted for condition score) at 4 years of age
Four-yr-oldFour-yr-old Four-yr-oldFour-yr-old Four-year-oldFour-year-old
BreedBreedHeightHeight
ininCondition Condition
ScoreScoreWeight / (Adj. Weight / (Adj.
Wt.) Wt.) LbLb
HerefordHereford 53.1ab 6.47a 1360 a (1348a)
AngusAngus 52.5bc 6.54a 1348 a (1342ab)
Red AngusRed Angus 52.2c 6.63a 1342 a (1321ab)
SimmentalSimmental 53.6a 6.40ab 1357 a (1353a)
GelbviehGelbvieh 52.9abc 6.01c 1273 b (1282b)
LimousinLimousin 53.5a 6.13bc 1320ab (1330ab)
CharolaisCharolais
LSD <0.05LSD <0.05
53.3ab
0.8
6.47a
.29
1344 a (1339ab)
54 (51)
source: Cundiff et al., 2005, Germplasm Evaluation Program
SimmentalComplimentary traits to Angus
• Muscle/Red Meat Yield• Growth• Efficiency• Maternal
Maintain• Marbling/QG• Calving ease• Market acceptability (phenotype,
color)• Mature size
Commercial Breeding Programs
Merchandise poundsGoal:
• Output per unit of input• Optimize performance within resources
while maintaining low cost
Tools• Selection pressure (within and across
breeds)• Breed differences• Mating system
Better Feeder Cattle…
Effectively Immunized
High GrowthEfficient Growth to
PayweightMeet Carcass
Target Specifications
Properly PackagedRight Price
Sire Profit
Rankings:
Feedyard
TCSCF, Strohbehn & Busby, 2014
Post Weaning Trait Correlations with
Lifetime ProfitabilityFinal Wt. 0.80Feed:Gain -
0.34ADG 0.67Carcass Wt. 0.85RE 0.51YG 0.15MB score 0.32CH- and up
0.35
Health cost-0.23
Cost of gain -0.41
TCSCF, Strohbehn & Busby, 2014
In Search of the Optimum Cow….
Calves successfully at 2 years, annually thereafter, with minimal calving difficulty
Weans valuable calf annually that fits demands of marketplace and satisfies consumers
Highly adapted to environment and managerial resources
Optimizes revenue vs. costs of production over long life
Returns a profit!
Maternal HeterosisAdvantage of the Crossbred Cow
Advantage of crossbred cow vs. straightbred• Reproductive efficiency• Maternal ability• Longevity
Increased lifetime productivity
Maternal heterosis accounts for largest portion of total heterosis advantage (60%)
Heritability and Heterosis of Various Traits and Their Impact on Components of Cow-Calf
Profitability
Trait Heritability
HeterosisImpact on Production
Costs
Impact onProduction
Output
Reproduction
Low High Favorable Positive
Calf Survival
Low High Favorable Positive
Longevity Low High Favorable Positive
Milk 20% Mod. Variable Positive
Calving Difficulty
15% Mod. Unfavorable Negative
Mature Size 50% Mod. Variable Positive
Calf Weight 40% Mod. Variable Positive
Genetic Targets OPTIMIZING
PRODUCTIVTY
Reproduction Calving
Ease/Survival Growth Maternal Ability Carcass Merit
MANAGE COSTS OF PRODUCTION
Reproduction Mature Size Milk Production Stayability
Benchmarks: PB Simm
Benchmarks: Simm Hybrid
Key Traits: Cow-Calf Calving Ease Direct Growth (weaning, post weaning) Carcass merit- RE, MB Maternal Calving Ease Milk Reproduction, Longevity, Stayability Mature size/frame Coat color Udder quality Phenotype
TSI
API
Seedstock ProgramsMerchandise breeding value
(genetics)Goal:
• Provide superior genetics for use by commercial producers
• Optimize investments in technology and costs of production with revenue
Tools• Selection pressure• Technologies
Seedstock: KeysFocus on the profitablity of their
customersBase decisions on data and
customer feedbackParticipate in total herd
enrollmentUtilize genetic technologiesEngaged in the success and
challenges of their customers
Genetic Positioning for the Future
Where have we been?Where are we now?Where are we going?How do we get there?
Beef Operations, Inventory, and Herd Size
Small Herds90% operations44% inventory
Large Herds10% operations56% inventory
NASS, USDA
Basic Principle of Genetic Improvement:
Any trait(s) of relevance must be measured and recorded to provide a
benchmark and basis for moving forward!
Importance of THEEPDs for economically relevant
traits which are particularly important to cow-calf producers• Reproduction• Stayability
Enhanced accuracy of selection for all reported traits (ie. better EPDs)
Sire Dam
WW EPD +40 WW EPD +30
WW EPD +40
WW EPD +35Individual Performance
Few Progeny
WW EPD +45
WW EPD +47
Many Progeny
Pedigree Estimate Low Accuracy 0.05-0.20
Low-Medium Accuracy 0.20-0.35
High Accuracy 0.80-0.99
Medium Accuracy 0.60-.80
Genomics
Genomic Influence on ACC
Genomic results incorporated into EPDs as correlated trait
Impact on ACC dependent on proportion of additive genetic variance explained by genomic result• Most traits 36-49%
Similar to 8-20 progeny records (trait dependent)
Influence of Information on EPDs and Accuracy
Yearling Bull- pedigree + own CE, BW, WW, YW (smaller amount of data)
CEDEPD
BW EPD
WWEPD
YWEPD
MilkEPD
+70.05
+1.90.05
+570.05
+1010.05
+220.05
+ genomics
+70.35
+1.00.35
+610.29
+1070.32
+230.24
GenomicsGenetic predictors for hard to
measure traits• Tenderness• Carcass• Heifer pregnancy• Intake/efficiency
Enhanced API
What about genetic diversity?
Genetic variation within breed is important to minimize inbreeding while allowing continued genetic progress
Pedigree diversity without compromising genetic merit
Key Traits: Cow-Calf Calving Ease Direct Growth (weaning, post weaning) Carcass merit- RE, MB Maternal Calving Ease Milk Reproduction, Longevity, Stayability Mature size/frame Coat color Udder quality Phenotype
TSI
API
Seedstock
Is Phenotype Economically Relevant?
Heritabilities of Phenotypic Traits
Stature (height) .60
Body length .39 Muscling .42 Capacity .44 Femininity .32 Rear legs (hock
set) .12 Foot/pastern
angle .13 Udder
attachment .23 Udder depth .35 Teat size .39
Kirschten, 2002
History of Showing Livestock
Historically to Promote IdealsEstimate Animal ValueEncourage Quality and Genetic
ChangePromotion of Livestock and Meat
IndustryPromotion of Individual ProgramsYouth Education and
Development
Today?Promotion of Individuals and Programs
Youth Development and Education
Promote Phenotypic IdealsAdd Value…..Promote Positive Genetic Change?
History of Performance Shows
Several Breeds Have ExperienceSimmental and Red Angus Substantial Cost…..Substantial Value?Created vs. Mitigated Controversy?Variation in the Priority and
Application of Genetic Info have been Substantial.
Variation in the Priority of Phenotypic Traits have been Substantial.
It’s Still Judging……..Bottom Line!
ASA Progress Through Performance (PTP) Shows
Encourage the incorporation of performance data in the showring
Educate breeders regarding EPDs and their use in the industry
Blending Shows and EPDsUse of EPDs enhances relevance to other
segments of industryEffects reputation/impression of breedAdds level of objectivity to showringJunior exhibitors- education, industry
applicationShows continue to be forum for
socialization, gathering of breeders and discussion
Phenotype is economically relevant, however not in leu of documented genetic merit
CE +7.1 (55%)
YW +83 (2%)
MB +0.21 (40%)
API +113 (30%)
TI +73 (3%)
CE +9.7 (40%)
YW +99 (1%)
MB +0.56 (20%)
API +134 (15%)
TI +95 (1%)
SummarySimmental is well positioned to be the
complimentary breed of choice to British genetics
Breeding programs should focus on complimentary traits relevant to all sectors of the industry
Technology (THE, DNA, etc.) are critical for assessing genetic merit and designing genetics
Phenotype is economically important, but not in leu of objective predictors of genetic merit