2001 NAAB / S-284 Meeting, Baltimore, 2001 (1) Implications of Crossbreeding on Dairy Cattle Improvement Paul VanRaden and Ashley Sanders Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (2) Protein kg/d % Holstein genes 0.86 — Holstein mean Crossbreeding Theory Holstein  Brown Swiss Protein Yield —A+Dominance (D) max heterosis (H) max heterosis (H) — A+D min H — A+D+A  A max H — A+D+A  A min H — Additive (A) only

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (3) Crossbreeding Research  Document current levels of crossbreeding in the US from DHI data.  3500 parent-identified crossbreds cows born in  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.

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (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  140,421 purebred herdmates (80% were Holstein).  Productive life data  41,131 crossbred cows born since  726,344 purebred herdmates.  Other traits  Body size breed means and heterosis from literature.  Udder, feet and legs, calving ease, etc. values were 0.

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (5) Breed Differences & Heterosis for Economic Merit Breed Net Merit ($) Cheese Merit ($) Fluid Merit ($) Ayrshire Brown Swiss Guernsey Jersey M. Shorthorn Holstein——— Heterosis$197$207$163

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (6) Merit of F 1 Holstein Crossbreds Second Breed Net Merit ($) Cheese Fluid Ayrshire Brown Swiss Guernsey Jersey M. Shorthorn Compared to 2000 genetic base for Holstein

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (7) Mates for Holstein Cows Brown Swiss Jersey Top US Sire Ransom Fan Club NM$ (breed scale) $519 $519 $467 $467 Breed Difference (from HOL) - $178 - $153 Heterosis (NM$) + $197 + $197 + $197 Adjusted NM$ (HOL scale) $538 $538 $511 $511 NM$ Rank (HOL scale) CM$ Rank (HOL scale)

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (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.

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (9) Sires with Many Crossbred Daughters Sire name SirebreedPurebreddaughtersDambreedCrossbreddaughters J Pete Rose BS2079HO90 M-B-S Berretta JE16,474HO74 I Quiet Revolution MS301HO21 LL Bell Hilton HO28,989GU18 V JS Bell Boss HO22,998AY15 Only 113 sires had > 10 crossbred daughters.

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (10) Conclusions

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (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.

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (12)

Paul VanRaden 2001 NAAB / S-284 Meeting, Baltimore, 2001 (13) 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%