1. Cross-Breeding
What is X-Breeding?

2. 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.

3. 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

4. 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.

5. 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.

6. 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

7. 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

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

9. Crossbreeding Theory Holstein  Brown Swiss Protein Yield25 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.

10. 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

11. 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

12. 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)
breed difference
heterosis
adjusted CM$ $612 $622

13. Conclusions

14. 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.

15. Holstein  Guernsey
USDA Yearbook of Agriculture 1947
From , 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 (McDowell and McDaniel, 1968).
Breeds were:
HOLSTEIN
JERSEY
GUERNSEY (female only – no proven GUE SIRE available)
RED DANE
Cows milked 3x, barn fed.

16. 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

17. 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

18. 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)