Now that most bull buyers go by the numbers in making seedstock-selection decisions, the question has shifted from if to how. What are the rules? What is the best way to sift through the many EPDs that accompany the pedigrees of virtually every lot in every sale? 

In a perfect world, every breeder would understand the strengths and weaknesses of every cow in the herd. This knowledge would lead to an understanding of strengths and weaknesses on a herd basis that would help guide the selection of bulls. Are calving difficulties too high? Are pay weights too low, and if so, is milk production too low and are growth genetics too weak? Is weaning weight too low relative to yearling weight? Do carcass qualities meet established goals? But how many of you have created a perfect world? Not many.

If a complete rulebook has been published on how to use EPDs in selecting bulls, I haven’t seen it. But a lot of good information containing useful rules has been published. Rule one is know your cows. If you haven’t created a perfect world through recordkeeping, think things through—create a useful profile. Rule two is know your bulls. If you haven’t been provided performance pedigrees on your bulls, get them. The EPDs on these pedigrees will show what you’re putting into your herd and give you a basis for making changes. Rule three is don’t single-trait select.  

Many of you (perhaps most) buy your bulls at a production sale. If you’re in this group, follow rule four—know your breeder. Today’s reputation breeder isn’t necessarily a firm with a trunk full of show ribbons. The firm is more apt to be one with a disciplined breeding program producing sound cattle with strong, balanced EPDs.    

A fifth rule to follow is do your homework. You should be way above the bull buyers who whip into a sale within an hour of starting time, flash through a few pens, scribble down a few lot numbers and be in the seats for the opening gavel (having gotten lunch on the way). Review the sale catalog before ever leaving home and make a list of qualified animals. If you arrive an hour before sale time, spend that time checking the soundness of the bulls on your list.

I derived the table below from the catalog of a reputation Angus breeder in the Midwest. I considered only ultrasound-derived carcass EPDs and I used the dollar indexes only as a final check. I looked for balanced bulls with particular strength in marbling, having not fared well on quality grade in my feedouts.

My first choice was lot six, a bull with a very acceptable marbling EPD, strong growth EPDs and with very strong and balanced EPDs for all other traits. I would have been guilty of single-trait selection if I had selected the lot five bull—his marbling EPD is exceptional but he’s a wienie on most other traits. And, his weak EPDs are supported by weak dollar indexes.

Your list would probably have been different from mine. My goal was to find the bull with the top EPD in each trait (including dollar indexes). Your list should contain several bulls that are strong in your EPD(s) of weakness. But always heed the advice of the experts, don’t single-trait select. You’ll find strengths for your weaknesses if you do your homework.

To contact Fred Knop, write Drovers or send e-mail to