Genomic-enhanced EPDs decrease risk of misclassifying young bulls
A recent analysis shows that adding genomic information to expected progeny differences can increase a producer's odds of selecting the most appropriate Angus sires for his or her individual herd goals.
Kent Andersen, Ph.D., associate director of technical services, Pfizer Animal Genetics, says this analysis further demonstrates how combining information from the High-Density 50K (HD 50K) panel to EPDs can reduce the risk of misclassifying young, unproven sires and help improve producers' purchasing decisions.
"In our analysis, among nonparent Angus bulls, we found that about one-third of the bulls selected based on their pedigree plus their own performance EPDs would not have been selected if we also used more dependable genomic-enhanced EPDs powered by HD 50K," he explains. "What's more, a similar number of bulls not selected based on their EPDs should have been based on their GE-EPDs."
Andersen says this doesn't mean the unselected bulls in this exercise aren't valuable, but the situation points to the benefits of fine-tuning breeding decisions with GE-EPDs. He adds that at least some of the sires in this analysis should simply be used for different purposes than originally thought based on their traditional, lower-accuracy EPDs.
These sires were ranked according to their EPDs for birth weight, weaning weight and marbling before and after the addition of information from HD 50K. The study included 463 registered Angus bulls that had initial weaning weight EPDs with nonparent accuracies and HD 50K results available to enable GE-EPDs. The criteria set for these sorts were based on multiple-trait selection of above-average EPDs for the three traits, as determined by the percentile rankings table from the American Angus Association.
The bulls that had birth weight EPDs less than 2.0, weaning weight EPDs greaterthan 46 and marbling EPDs greater than 0.39 were considered "selected" sire candidates. This multi-trait sort initially selected 95 bulls, or 20 percent of the offering. Then genomic predictions from HD 50K were added to each sire's EPDs, and the bulls were sorted again based on the same criteria applied to their GE-EPDs.
The results showed that 33 of the original 95 selected bulls--or 35 percent--did not meet the selection criteria after the addition of genomic information. In addition, 43 bulls that did not meet the original EPD thresholds now met the criteria and should have been selected based on their GE-EPDs.
"This suggests that when making multi-trait selection decisions with traditional nonparent EPDs alone, producers run the risk of misclassifying young, unproven bulls," Andersen says. "The great news is that Black Angus breeders and commercial buyers of Angus genetics have the option to receive genomic-enhanced EPDs powered by HD 50K."
GE-EPDs powered by HD 50K are available from Angus Genetics, Inc., a subsidiary of the AAA. HD 50K is the beef industry's first and only commercially available high-density DNA panel with more than 54,000 markers and information related to 18 economically important traits, including calving ease; growth and efficiency; maternal performance; and carcass yield and quality. Parentage also is verified with HD 50K at no additional cost when samples are submitted to AGI.
Adding HD 50K information increases EPD accuracy values equal to the addition of seven to 20 progeny performance records, depending on the trait, which helps illustrate why producers risk misclassifying young bulls, and why Andersen recommends producers looking to buy young Angus sires request GE-EPDs powered by HD 50K.