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Implications of Crossbreeding on Dairy Cattle Improvement

Implications of Crossbreeding on Dairy Cattle Improvement. Paul VanRaden and Ashley Sanders Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD paul@aipl.arsusda.gov, asanders@aipl.arsusda.gov. Crossbreeding Theory Holstein  Brown Swiss Protein Yield.

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Implications of Crossbreeding on Dairy Cattle Improvement

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  1. Implications of Crossbreeding on Dairy Cattle Improvement Paul VanRaden and Ashley Sanders Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD paul@aipl.arsusda.gov, asanders@aipl.arsusda.gov

  2. Crossbreeding TheoryHolstein  Brown Swiss Protein Yield 0.96 0.94 0.92 Protein kg/d — Holstein mean — Additive (A) only 0.90 —A+Dominance (D) max heterosis (H) 0.88 — A+D min H — A+D+AA max H 0.86 — A+D+AA min H 0 25 50 75 100 % Holstein genes

  3. Crossbreeding Research • Document current levels of crossbreeding in the US from DHI data. • 3500 parent-identified crossbreds cows born in 1997. • 600,000 sire-identified Holsteins. • 35,000 sire-identified Jerseys. • Determine if crossbreeding makes sense in dairy cattle. • If yes, advise breeders on possible selection and mating systems across breeds.

  4. Crossbred and Purebred Data • Yield and SCS data • 572 herds each with at least 5 crossbred cows. • 10,442 F1 crossbred cows born since 1990. • 140,421 purebred herdmates (80% were Holstein). • Productive life data • 41,131 crossbred cows born since 1960. • 726,344 purebred herdmates. • Other traits • Body size breed means and heterosis from literature. • Udder, feet and legs, calving ease, etc. values were 0.

  5. Breed Differences & Heterosis for Economic Merit

  6. Merit of F1 Holstein Crossbreds Compared to 2000 genetic base for Holstein

  7. Mates for Holstein Cows

  8. Separate or Combined Breed Evaluations • Separate data sets reduce bias in evaluations within breeds, but some information is lost: • Crossbred cows evaluated inaccurately or not at all • “Conversion formulas” to compare cows across breeds • New Zealand, Australia, and the Netherlands include crossbreds and account for heterosis in evaluations. • USDA-DHIA evaluations exclude crossbred cows unless identified as part of a “grading-up” program.

  9. Sires with Many Crossbred Daughters

  10. Conclusions

  11. Conclusions • Currently< 0.5% of DHI cows are crossbred. • Heterosis was about 4% for yield traits, < 1% (unfavorable) for SCS, and 1% for PL. • Profit from Jersey  Holstein and Brown Swiss  Holstein crosses was higher than from Holsteins when compared at PTA = 0. • Fewer extreme PTA bulls are found in minor breeds. • Matings with high additive merit and low inbreeding make sense.

  12. Complete Outcross Pedigree! • Advertisement for Bullcrest Patron Sabre • SIRE: Patron = Blackstar x Ned Boy x Bell • MGS: Roebuck = Mark x Bell x Sexation • MGGS: Tong = Mars Tony x Chief x Astronaut • MGGD = Chairman x Valiant x Elevation • Future daughter inbreeding = 5.6% • Average for active AI Holsteins = 4.9% • Inbreeding when mated to Jerseys = 0.0%

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