Cross-Breeding What is X-Breeding?

Objectives Document the number and type of crossbred cows in the US. Estimate heterosis and breed differences using cows of different breed composition competing in the same herd. Compare the economic merit of crossbred and purebred cows.

Traits Considered Milk, fat, and protein yields Somatic cell score (SCS) Productive life (PL) Linear type composites not available Body size estimates obtained from literature Udder and leg trait estimates assumed zero Net merit, cheese merit, fluid merit calculated Adjusted to Holstein scale Fertility, mortality, and calving ease not available

Breeds Are Evaluated Separately Separate data sets reduce bias in evaluations within breeds, but provide: No evaluations for crossbreds No method 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.

Yield Traits & SCS Data Data were from the national test-day database available May, 2001. 572 herds each with at least 5 crossbred cows 10,442 crossbred cows born since 1990 140,421 purebred herdmates (80% were Holstein) Crossbreds defined by sire breed and maternal grandparent breeds. Sires were purebred, dam breed used for unknown maternal grandparent breed XX (crossbred) not accepted for maternal grandparents Holstein and Red & White considered one breed Because XB’s are not routinely evaluated, pedigree reported less often/completely May leads to under-count of XB’s Started with 12,565 XB in ~3,300 herds Restricting data to herds with >= 5 XB cows retained more than 80% of XB’s but reduced herds by more than 80% greatly reducing computing time.

Number of F1 & Purebred Cows In Mixed Breed Contemporary Groups Sire Breed Dam Breed Ayrshire Brown Swiss Guernsey Jersey Milking Shorthorn Holstein 933 — 1 26 2 477 2537 8 22 5 242 31 1763 23 4 1228 18 11 6593 507 M. Shorthorn 1509 175 145 819 130 1631 162 71,836

Number of F1 & Backcross Cows With Holstein Sire or Grandparent Holstein Genes Second Breed 25% 50% 75% Ayrshire 17 622 124 Brown Swiss 1061 196 Guernsey 32 1358 367 Jersey 171 2138 321 M. Shorthorn 14 337 48

Results Estimated breed means Estimates of heterosis Economic comparisons Rank other breeds on Holstein base Some new crossbreeding theory

Crossbreeding Theory Holstein  Brown Swiss Protein Yield 25 50 75 100 0.88 0.90 0.92 0.94 0.96 Protein kg/d % Holstein genes 0.86 — A+D+AA max H — A+Dominance (D) max heterosis (H) — A+D+AA min H — A+D min H — Additive (A) only — Holstein mean Recombination effect was positive in this study. Effects shown are weighted average of reciprocal cross types; possible maternal effects are ignored.

Breed Differences & Heterosis for Economic Merit Net Merit ($) Cheese Fluid Ayrshire -510 -469 -728 Brown Swiss -355 -256 -808 Guernsey -761 -692 -1117 Jersey -305 -186 -865 M. Shorthorn -892 -862 -1073 Holstein — Heterosis $197 $207 $163

Merit of F1 Holstein Crossbreds Second Breed Net Merit ($) Cheese Fluid Ayrshire -58 -27 -201 Brown Swiss 18 79 -241 Guernsey -184 -138 -395 Jersey 44 113 -269 M. Shorthorn -249 -223 -373 Compared to 2000 genetic base for Holstein

Mates for Holstein Cows Brown Swiss Jersey Top US Sire Ransom Fan Club NM$ (breed scale) $519 $467 Breed Difference (from HOL) - $178 - $153 Heterosis (NM$) + $197 Adjusted NM$ (HOL scale) $538 $511 NM$ Rank (HOL scale) 28 40 CM$ Rank (HOL scale) 13 12 Cheese Merit Calculations: Ransom Fan CLub CM$ (breed) 533 509 breed difference -128 -94 heterosis +207 +207 adjusted CM$ $612 $622

Conclusions

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 is higher than from Holsteins. Fewer extreme bulls are found in minor breeds. Backcross yields were higher than expected.

Holstein  Guernsey USDA Yearbook of Agriculture 1947 From 1939-1954, M.H. Fohrman studied 113 Guernsey, Jersey, Holstein, and Red Danes crosses at Beltsville. Another study of 137 Ayrshire, Brown Swiss and Holstein crosses was conducted from 1959-1968 (McDowell and McDaniel, 1968). Breeds were: HOLSTEIN JERSEY GUERNSEY (female only – no proven GUE SIRE available) RED DANE Cows milked 3x, barn fed.

Holstein  Jersey Cow # Pounds of Milk % Butterfat Pounds of Butterfat USDA Yearbook of Agriculture 1947 Cow # Pounds of Milk % Butterfat Pounds of Butterfat X-5 13,032 4.62 602 X-11 12,584 4.82 606 X-20 12,383 5.13 636 X-30 11,867 5.60 664 X-38 11,929 5.09 607 X-40 13,690 4.74 649 X-51 13,800 4.44 613 Results From Fohrman et. al HOLSTEIN SIRE PROOF: 644lbs daus>dam milk (18,416 vs 17,772) 26lbs daus>dam fat (645 vs 619) #DAUS=31 AVG: 12755lbs milk (3670kg) 4.92% fat 625lbs fat (150kg) All cows sired by Beltsville Holstein No. 966

Jersey  Holstein Cow # Pounds of Milk % Butterfat Pounds of Butterfat USDA Yearbook of Agriculture 1947 Cow # Pounds of Milk % Butterfat Pounds of Butterfat X-1 9,784 4.85 475 X-3 13,065 4.71 615 X-17 13,837 3.85 533 X-32 13,728 3.94 540 X-41 12,453 4.63 576 X-42 9,417 4.90 461 X-47 12,189 5.13 625 AVG: 13054lbs milk (5760kg) 4.57% fat 546lbs protein (260kg) X-1 and X-47 were sired by an unidentified Jersey sire. All others sired by Beltsville Jersey No. 1114

Three-Breed Crosses USDA Yearbook of Agriculture 1947 Butterfat yield of three breed crosses was greater than from their F1 crossbred dams. Three breed crosses averaged 14,927 pounds of milk and 641 pounds of butterfat as 2-year-olds in 1947. 6660kg milk 290kg fat No predictions based on f1 daus:dam so don’t know whether this can be attributed to ‘hybrid vigor’ This group was heavy on the Red Dane sire These were 3 breed crosses, so more hybrid vigor should be maintained (~85% in 3 breed rotations), as opposed to rotating only 2 breeds (~65% in 2 breed rotations)