Date of this Version
In question and answer format this NebGuide addresses changes in genetic evaluations of both dairy cows and sores.
Why is the United States Department of Agriculture (USDA) changing the dairy sire and cow evaluation system?
The answer is simple. The Animal Model for genetic evaluations is more accurate than the old Modified Contemporary Comparison Method (M.C.C.). Previously the major limiting factors to implementing the Animal Model were computing costs and memory requirements. With the advent of new Super Computers, the computations are feasible on a national scale.
What is the Animal Model?
The Animal Model simultaneously evaluates cows and sires using all their ancestor relationships. This means that every animal known in a given pedigree is used to evaluate both the cow and sire. This increases the accuracy of evaluation and should be a major step in breeder acceptance of the new evaluation system.
Not only are all registered animal pedigrees included in the evaluation process, but all non-registered cattle pedigrees that have been identified properly on Dairy Herd Improvement (DHI) testing are included.