Bull Search

Impact On Reliability

 

Are bull rankings the same with traditional evaluations and genomic enhanced evaluations?

Some re-ranking will occur as new information is added to the breeding value. In general, first crop bulls will have a similar ranking. However, the added information and reliability of the genomic enhanced evaluations mean that some bulls will move up and some will move down. Second Crop ABS Diamond Sires are the most accurately proven sires in the industry and therefore have the most stable proofs.

What causes genomic proofs on cows and bulls to change over time?

Genomic enhanced evaluation results on young and proven animals alike will change over time as new information is added. Each of the three pieces of information, that is blended for the genomic enhanced evaluation – 1) genomic information, 2) any remaining pedigree contributions, and 3) information from daughters – will change as new information is added. Adding new genotyped proven bulls and their respective daughter information impacts genomic information for all bulls that share some of those same genotypes. Adding new daughters also influences proofs for their sires. Both of these factors will influence pedigree components. Ultimately, all of these additions of new information will impact genomic enhanced evaluations over time.

 

How do I know if a bull has a genomic proof?

Holstein Association USA plans to use genomic enhanced evaluation results to compute genomic TPI labeled as GTPI for bulls and cows that have been genotyped. Essentially all actively marketed Holstein and Jersey bulls in the January 2009 ABS U.S. Dairy Profit Power will have been genomic tested.

 

How are international bulls and proofs handled?

Genomic enhanced evaluation results from the USDA apply to their U.S. proof only. The PTA data that goes to Interbull for international publication contains only the traditional PTA data. There is no mechanism in place currently at Interbull to handle the genomic enhanced evaluations being published by USDA. Equally, Interbull has no procedures in place to handle genomic enhanced evaluations being calculated by A.I. companies in Holland and New Zealand. As a result, international bulls with MACE proofs and no U.S. genomic proof that are marketed in the U.S. will use their traditional PTAs only.