1 / 13

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.

mateja
Télécharger la présentation

Implications of Crossbreeding on Dairy Cattle Improvement

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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%

More Related