Jared E. Decker Associate Professor, Division of Animal Sciences, University of Missouri
Reprinted with permission from The Cattlemen and Santa Gertrudis Breeders International.
Can we be frank
for a minute? It is quite simple: EPDs work. When we use EPDs to make selection
decisions (which bulls to buy, which females to keep and cull), the performance
of our herd improves. Let’s discuss why EPDs work, how they can be used, and
pitfalls to avoid. Defining EPDEPD stands for
Expected Progeny Difference. “Expected” in this context is a loaded word. We
use it here the way a statistician would use it. Expected means we are
describing a prediction of the future. Expected also means we are discussing an
average, not a single observation. What is the average that we are predicting
with EPDs? We are predicting the average progeny, or the average of an animal’s
calf crop. Finally, when we are discussing EPDs we are discussing differences.
Either the difference between two animals or the difference b…
Bob Hough recently posted the following comment on Facebook (posted with his permission): Early in my career at a breed association, the much beloved American Angus breed executive told me that the secret to success running a breed association was to have a top junior program, keep the books straight, and make sure the numbers (EPDs) don't change. This philosophy meant Angus valued stability in their genetic predictions over keeping them up-to-date with the latest science. The Angus Association also marketed extremely effectively the infallibility of their EPDs because of the size of their database. I will start with the later. Yes, a database needs certain critical mass to make sure the animals are tied, but that can be achieved in a modest size database. After that, data quality far and away outweighs data quantity in assuring the most precise and reliable EPDs possible. On the former point, Angus breeders are simply not use to change. This is not the case in most breed associati…
At the January 4th Show-Me-Select Board of Directors meeting, new service sire EPD requirements were approved. All sires, artificial insemination and natural service, must meet minimum Calving Ease Direct (CED) EPD requirements. In addition to yearly updates, two changes were made.
First, no Birth Weight EPD requirement will be published. All commonly used breeds now have CED EPDs available.
Second, all breeds in the International Genetic Solutions (IGS) genetic evaluation are now set to a common requirement. In the summer of 2018, breeds within the International Genetic Solutions switched to a single-step BOLT multi-breed genetic evaluation. The EPDs for animals in the IGS genetic evaluation are directly comparable across breeds.