A Steak in Genomics™

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 EPD EPD 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 animal

Updates are based on a major research effort and will be effective this June. The American Angus Association® Board of Directors approved changes to the $Value Indexes during the February board meeting Feb. 18-21, 2019. Updated $Value Indexes will be available this June, and changes include revisions to Beef Value ($B), updating the Weaned Calf Value ($W) model to the new Maternal Value ($Maternal) and rounding all $Values to whole dollars to eliminate decimals. Quality Grade ($QG) and Yield Grade ($YG) will be removed because $QG is redundant to the Marbling EPD, and $YG is redundant to Fat and REA EPDs. In addition, a balanced index will be implemented June 2020 with a complete education plan to be executed with the membership and industry to take place over the next 15 months. “Our current $Value Index models have served us well since 2004,” said Dan Moser, Angus Genetics Inc. president. “But since 2004, technology has improved, and new EPDs have been created. So, an extens

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 associ