Sunday, October 30, 2011

How to Get EPDs on Your Purebred Angus

Breed Development — Using EPDs

Expected Progeny Differences (EPDs) are the most powerful genetic tool we have for selecting the best animals for your breeding program.
EPDs are values that predict how the future progeny of an animal will perform relative to the progeny of other animals in the same breed. They are expressed in the units of that particular trait. For example, weaning weight is measured in pounds thus the Weaning Weight EPD is expressed in pounds. Another way to look at it is EPDs measure an animal’s value as a parent.
EPDs are based on pedigree information and performance data such as weight information and are then compared to other animals within a contemporary group. The different traits are adjusted to a standard age to ensure that all animals are equal when they are compared. The traits are adjusted as follows:
  • 205 days of age for weaning weight
  • 365 days of age for yearling weight
  • 365 days of age for bulls in ultrasound
  • 390 days of age for heifers in ultrasound
EPDs are then calculated using complex statistical procedures twice each year during the National Cattle Evaluation (NCE).
To ensure that your animals receive EPDs you must:
1.  Be enrolled in the Canadian Angus Performance Program (CAPP).
2.  Submit weaning weights on all of your animals.
3.  Place your animals in a (same sex) contemporary group of more than two.
4.  Ensure your animals are within the acceptable age ranges:
a.      130–280 days for WW for red Angus animals
b.      120–280 days for WW for black Angus animals
c.       290–440 days for YW for all Angus animals
5.  Animals that are in a management group of their own, such as twins, fosters, ET calves and lone bull calves are automatically placed into a single animal contemporary group and will not receive EPDs until they are parents to performance-recorded progeny.
To use EPDs effectively you must understand how they work. Imagine you are interested in purchasing a couple of bulls for your herd. You are looking at the EPDs in a sale catalogue. Bull A has a weaning weight EPD of +10 and Bull B has a WW of +60. What does that mean? How can you use the EPDs to choose between the two bulls?
If these animals were randomly mated with 10 similar cows, we would expect the group average weaning weight of Bull A’s offspring to be 50 lbs lighter than that of Bull B’s (60-10=50).

For complete information on EPDs from the CAA, click on this link,