Making Sense of EPDs: A Guide to Better Bull Selection for Beef Producers

When it comes to improving the genetics of a cow herd, few tools have had as much impact in recent decades as Expected Progeny Differences (EPDs). For both purebred breeders and commercial cattle producers, EPDs offer valuable insight into how a bull is likely to perform as a sire. But EPDs are only as useful as the understanding behind them.

What Are EPDs?

EPDs are predictions of how a bull’s calves will perform compared to the calves of another bull within the same breed. They are calculated using performance records, pedigree information, and — once available — progeny data. Traits most commonly tracked include birth weight, weaning weight, yearling weight, and milk production, but many breed associations also publish EPDs for calving ease, stayability, carcass traits, and more.

Three Key Questions Before Using EPDs

1. Who calculated the EPD?

Breed associations generate EPDs, but it’s important to know whether the figures are Canadian, American, or combined North American averages. Canadian and U.S. numbers may not always be directly comparable, and EPDs from different breeds are never directly comparable.

2. How does the EPD compare to breed averages?

An EPD value only has meaning when compared against the breed average for that year. For example, a bull with a yearling weight EPD of +12 may look strong at first glance. But if the breed average is +47, that bull is actually well below average for growth. Knowing the breed average helps producers understand whether a bull is suited as a terminal sire or better for producing moderate, efficient replacement females.

3. What is the accuracy of the EPD?

Accuracy tells you how reliable the number is. Young bulls often have low accuracy scores because the figures are based mostly on pedigree information, not actual calf performance. As more progeny data is collected, accuracy improves. Low-accuracy bulls aren’t necessarily poor choices, but producers should recognize that their numbers may shift over time. Proven sires with many progeny records have higher accuracy and more dependable EPDs.

Using EPDs in Breeding Programs

EPDs are a tool, not a stand-alone decision maker. When selecting herd sires, producers should:

• Define breeding objectives clearly.

  • Selling calves at weaning? Focus on birth weight, weaning weight, and maternal traits if replacements are retained.

  • Selling as yearlings? Yearling weight matters most, along with calving ease and maternal performance.

  • Retaining ownership through to slaughter? Carcass weight, yield, and grade come into play.

• Avoid single-trait selection. Chasing extreme growth or milk traits can create problems like calving difficulty or higher feed costs. Balance matters.

• Match breed to goals. Different breeds bring different strengths, and crossbreeding can enhance hard-to-improve traits through hybrid vigor.

• Choose within breed wisely. Once you’ve identified the right breed, select bulls whose EPDs align with your herd’s needs and your long-term goals.

Practical Takeaway

EPDs are one of the most valuable tools beef producers have to make informed bull selections. But to use them effectively, you need to know who calculated them, how they compare to breed averages, and how accurate they are. Combined with visual appraisal and sound management records, EPDs can help guide balanced decisions that improve genetics and profitability across your herd.