Revised estimates of lifetime Net Merit for dairy breeds and breed crosses

Paul VanRaden and Melvin Tooker*Paul VanRaden and Melvin Tooker*

Animal Improvement Programs LaboratoryAgricultural Research Service, USDA, Beltsville, [email protected]

2006

Revised estimates of lifetime Revised estimates of lifetime Net Merit for dairy breeds and Net Merit for dairy breeds and

breed crossesbreed crosses

Joint ADSA/ASAS Annual Meeting, July 2006 (2) VanRaden & Tooker200

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IntroductionIntroduction

Previous estimates used net merit (NM$), cheese merit (CM$), and fluid merit (FM$) formulas from 2000

Dairy breeds and breed crosses were compared using updated NM$, CM$, and FM$ formulas that include daughter pregnancy rate (DPR), calving ease, and stillbirth


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Data and MethodsData and Methods

National data for milk, fat, protein, productive life, SCS, and DPR were each evaluated using an all-breed animal model

New estimates of breed differences were compared to phenotypic breed differences and to previous estimates from studies that only included herds containing crossbred cows


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Breed Effects and HeterosisBreed Effects and Heterosis

New estimates of breed differences were generally intermediate between the previous estimates and the phenotypic breed differences; all three estimates were similar

Estimates of general heterosis from previous studies were used in the current research and not re-estimated


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Breed Effects and HeterosisBreed Effects and HeterosisTransmitting ability differences from HolsteinTransmitting ability differences from Holstein

Milk kg

Fat kg

Pro kg SCS PL DPR

Jersey −1698 −23 −29 +0.12 +2.0 +2.5

B. Swiss −927 −15 −13 −0.08 +0.1 +0.5

Guernsey −1996 −43 −50 +0.10 −0.9 +0.5

Ayrshire −1616 −50 −43 −0.07 +1.0 +1.1

M. Short. −1851 −70 −51 0.00 +0.8 +1.7

Heterosis +318 +16 +12 +0.02 +0.3 +1.8Heterosis and DPR estimates are from previous research


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Other Trait EstimatesOther Trait Estimates Body size composite estimated from

mature weight Udder composite, Feet & Leg composite

extrapolated from regressions on other traits within Holsteins• Size, PL, milk, DPR, SCS

Breed means for calving ease and for stillbirth• 7.3 million HO, 37000 JE, 17000 BS, 2000

GU, 2000 AY, 300 MS


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Trait Correlations within HolsteinsTrait Correlations within Holsteins(and Jersey correlations for comparison)(and Jersey correlations for comparison)

BreedCorr with Size PL SCS DPR Milk

HO Udder .26 .30 −.33 .03 −.20

HO F&L .22 .19 −.02 −.04 −.02

JE Udder .36 .41 −.21 .13 −.02

JE F&L .53 .20 .02 .21 −.08


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Assumed Effects – Other TraitsAssumed Effects – Other TraitsTransmitting ability differences from HolsteinTransmitting ability differences from Holstein

Size Udder F&LCalving Difficulty

Still-birth

Jersey −10.4 −1.4 −2.1 −7.1 −1.5

B. Swiss 0.0 0.7 0.3 −3.2 −0.7

Guernsey −7.3 −0.5 −1.3 −4.6 1.1

Ayrshire −5.8 −1.6 −0.9 −3.5 −1.2

M. Short. −4.2 0.1 −0.6 −0.1 −2.4

Heterosis 0.9 0.0 0.0 0.0 0.0


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Net Merit Relative EmphasisNet Merit Relative Emphasis

Trait 2003 2006 Trait 2003 2006

Protein 33 23 Udder 7 6

Fat 22 23 F&L 4 3

Milk 0 0 Size 3 4

PL 11 17 DPR 7 9

SCS 9 9 CA$ 4 6

DPR = daughter pregnancy rate (fertility), CA$ is index of calving ease and stillbirth


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NM$, FM$, CM$ - Economic ValuesNM$, FM$, CM$ - Economic Values

NM$ FM$ CM$

Milk 0.00 0.11 −0.07

Fat 2.70 2.70 2.70

Protein 3.55 0.00 5.73

Other values are same in each index:

PL 29, SCS -150, Size -14, Udder 28, F&L 13, DPR 21, CA$ 1


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Merit of FMerit of F11 Holstein Crossbreds Holstein Crossbreds

Second Breed NM$ CM$ FM$

Ayrshire −304 −261 −364

Brown Swiss 55 139 −78

Guernsey −408 −405 −503

Jersey 31 153 −158

M. Shorthorn −498 −461 −547

Compared to 2005 genetic base for Holstein


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Later Generation CrossesLater Generation Crosses

Holstein backcross or

multi-breed NM$ CM$ FM$

HO x (BS x HO) +28 +70 −39

HO x (JE x HO) +16 +77 −79

BS x (JE x HO) −32 +109 −251

JE x (BS x HO) −44 +116 −292

HO x (BS x JE) +44 +147 −118

Compared to 2005 genetic base for Holstein


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““Exotic” BreedsExotic” Breeds

US has pedigree records for other breeds; but very little production data

For further information:• Interbull conversions to Ayrshire

base• U. Minnesota scientists (Heins et al.)


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ConclusionsConclusions

Breed effects were re-estimated• Yield, PL, SCS, DPR by all-breed model• Udder, F&L composites from other traits• Calving ease and stillbirth breed means

New Net Merit formula for August 2006

Holsteins still superior for FM$


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ConclusionsConclusions

HO x BS and HO x JE higher for NM$ and CM$

BS x JE higher than HO for CM$

Three breed crosses (HO, BS, JE) are higher than HO backcrosses for CM$, similar for NM$

Documents

Revised estimates of lifetime Net Merit for dairy breeds and breed crosses