1	Genetic Evaluations for Mixed Breed Populations
2	Goals Evaluate crossbred animals without biasing purebred evaluations Accurately estimate breed differences Compute national evaluations and examine changes PTA’s of purebreds and crossbreds Changes in reliability Display results without confusion
3	Methods All-breed animal model Purebreds and crossbreds together Unknown parents grouped by breed Variance adjustments by breed Age adjust to 36 months, not mature 1988 software, good convergence Within-breed-of-sire model examined but not used
4	Unknown Parent Groups Groups formed based on Birth year (flexible) Breed (must have >10,000 cows) Path (dams of cows, sires of cows, parents of bulls) Origin (domestic vs other countries) Paths have >1000 in last 15 years Groups each have >500 animals
5	Data Numbers of cows of all breeds 22.6 million for milk and fat 16.1 million for protein 22.5 million for productive life 19.9 million for daughter pregnancy rate 10.5 million for somatic cell score Type evaluated in separate breed files Calving ease joint HO, BS, and HO x BS Goats in all-breed model since 1988
6	Crossbred Cows with 1^st parity records
7	Recent Sires of Crossbred Cows Sires born since 1997
8	Reliability Crossbred cows Will have PTAs, most did not before Accurate PTAs from both parents Purebred animals Information from crossbred relatives More contemporaries
9	All- vs Within-Breed Evaluations Correlations of PTA Milk
10	Display of PTAs Genetic base Convert all-breed base back to within-breed-of-sire bases Each animal gets just one PTA PTA_brd = (PTA_all – mean_brd) SD_brd/SD_all Heterosis and inbreeding Both effects removed in the animal model Heterosis added to crossbred animal PTA Expected Future Inbreeding (EFI) and merit differ with mate breed
11	Genetic Standard Deviation Ratios
12	Schedule Interbull test run Sept. 1, 2006 Trend validation Convert all-breed PTA back to within-breed bases Scientific publication (JDS) Implementation Expected February 2007
13	Conclusions All breed model accounts for: General heterosis Unknown parent groups by breed Heterogeneous variance by breed PTA converted back to within breed bases, crossbreds to breed of sire PTA changes more in breeds with fewer animals