Bulls - And the most important EPDs

Written By Wesley Harper

Recently, I have been taking some classes as a part of the Virginia Master Cattlemen’s Program, offered by the Virginia Cooperative Extension and Virginia Tech. A recent class on genetics was particularly interesting and answered many of my own questions regarding the best Bulls and EPDs for our cattle operation, so I thought I would share some of this information. With many large bull sales coming up in our area, I hope this information is valuable to some folks.

What Are EPDs?

Expected Progeny Differences, or EPDs for short, allow for the comparison of animals within a breed for their genetic potential as parents for a given trait. This can be used as a prediction of how future progeny of each animal are expected to perform relative to the progeny of other animals of the same breed.

In short, they are specific traits along with guesses of how well that animal will exhibit that trait.

Some examples of EPDs and what they mean to farmers:

  • CED - Calving Ease Direct: Predicts the likelihood of an unassisted birth with cows bred to that particular bull. This is typically associated with a lower calf birth weight, so that the cow has increased chances of birthing successfully and without complications. This is very popular with Cow/Calf operations.

  • BW - Birth Weight: Predicts the ability of the Bull to transmit birth weight to his progeny - predicting the birth weight of the calves.

  • WW - Weaning Weight: Predicts the ability of the Bull to transmit weaning weight to his progeny - predicting the weight of the calves at the time of weaning.

  • YW - Yearling Weight: Predicts the ability of the Bull to transmit yearling weight to his progeny - predicting the weight of the calves at one year of age.

  • Doc - Docility: Predicts the average temperament of the Bull’s progeny - A higher value indicates more docile traits.

  • MARB - Marbling: Predicts the amount of fat marbling in the finished meat - Based on USDA marbling scores.

  • RE - Ribeye Area: Predicts the size of the ribeye area in the animal.

What is an Index?

In addition to EPDs, there are also Index values. An index is a collection of certain economic traits that are expected to be passed down to the progeny of the Bull.

  • $M - Maternal Weaned Calf Value: Predicts the overall profitability of the replacement heifers you keep in your own operation, assuming up to 25% of heifers are kept as replacement heifers - Traits included in this index are calving ease direct, calving ease maternal, weaning weight, milk, heifer pregnancy, docility, mature cow weight, claw set and foot angle.

  • $B - Beef Value: Predicts the overall profitability of calves raised and sold to feedlots for beef consumption - Traits include yearling weight, dry-matter intake, marbling, carcass weight, ribeye area and fat.

  • $C - Combined Value: A combination of the $M and $B indexes, assumes the operation will retain 20% of their own replacement heifers and market the remaining animals to a feedlot operation for beef consumption. Predicts the overall profitability in a standard commercial operations setting.

You can find examples of more EPDs and Indexes for commercial Angus cattle here.

How are EPDs determined?

Associations for each breed keep records of performance for each particular breed of animal. Records are submitted by producers and recorded in a database to track performance improvements of particular bloodlines and progenies. This data comes from an animal's performance, as well as the performance of its relatives and progeny. EPDs can also be predicted by directly investigating an animal's DNA, which are called genomic EPDs.

What are the best EPDs for me?

The right EPDs for you will depend on your specific goals and operation. There is no such thing as “The Perfect Bull”, only the “Perfect Bull For You”. You have to determine which traits are most favorable to you to achieve the outcome you desire.

For example, if you are a cow/calf operation that wants to minimize time dealing with calf birthing complications, you might want to select a bull with an increased CED score. If you are trying to maximize your price/pound value when you take your calves to market, you might want to select a bull with an increased BW and WW score. If you want to retain high quality replacement heifers, then you should keep an eye on the $M score. Take time to think about your goals and operation to select the best bull for you.

If you are considering buying a registered Angus bull anytime soon, keep these resources in mind:

A sample EPD report from a bull sold by Miller Farm, LLC.

Wesley Harper