ARSBC 2018: EPDs and Reasonable Expectations in Commercial Crossbred Operations

Jared Decker, PhD University of Missouri One point must be clear from the very beginning: EPDs work . When we select parents based on EPDs the genetic merit for that trait increases in our herd. When we select the parents using EPDs the performance of the next generation improves. EPDs Defined EPD stands for Expected Progeny Difference. These three words are loaded with meaning, thus the need to define them here. The most loaded word is Expected. Here we use Expected the way a statistician would use the word. Expected means we are making a prediction of a future value. But, in this context, Expected also means we are describing the average of a group. What is the group for which we are predicting the average? We are predicting the average performance of the Progeny or calves out of an animal. An animal’s own performance and its EPD can be quite different, because that is not the purpose of an EPD. The EPD is predicting the average performance of that animal’s calf crop. Final