The Dickinson Research Extension Center tries to buy bulls low in birth weight, moderate in growth and milk and excelling in carcass traits. Bulls with these genetics are for sale and, with some bidding, are available to bring home.
Bull buying can be repetitive. Expected progeny differences (EPDs) get checked, rechecked and used. After post-breeding season culling, the center checks EPDs to make sure the right genes are transmitted into the cow herd. The process begins again each year by evaluating the genetics of the “keeper bulls” prior to going out and bidding on similar or better bulls.
Last week, I discussed the Angus bulls and noted that the Red Angus and Simmental bulls would be reviewed this week. I like to start with the basic growth traits, which are those “touchy, feely” kinds of traits I can see. The baseline EPD growth traits I look at are birth weight, weaning weight and yearling weight.
Last year, the center’s breeding lineup for Red Angus bulls had an average EPD value for birth weight of minus 0.9 pound, weaning weight of 62 pounds and yearling weight of 105 pounds. After culling, the “keeper” Red Angus bulls averaged minus 1.2 pounds for birth weight, 64 pounds weaning weight and 108 pounds yearling weight. The center’s “keeper” Red Angus bulls have less birth weight but similar to slightly improved weaning weight and yearling weight, compared with the previous year.
As noted, the 50 percentile of the Red Angus breed had the average EPD value for proven and genetic opportunity sires of minus 1.6 pounds for birth weight, 55 pounds for weaning weight and 86 pounds for yearling weight. In addition, the “keeper” Red Angus bulls had an average rib- eye area EPD of .36 and marbling EPD of .51, which are both well above the 50 percentile of the Red Angus breed. Those Red Angus breed values for rib-eye area EPD are .10 and a marbling EPD of .41 unit of marbling score.
I will review the same traits for the Simmental bulls. Last year, the center’s breeding lineup for Simmental bulls had an average EPD value for birth weight of 2.4 pounds, weaning weight of 76 pounds and yearling weight of 108 pounds. After culling, the “keeper” Simmental bulls averaged 2.4 pounds birth weight, 81 pounds weaning weight and 112 pounds yearling weight. The center’s “keeper” Simmental bulls have the same birth weight and similar to slightly improved weaning weight and yearling weight, compared with the previous year.
Within the Simmental breed, the 50 percentile ranking for the average EPD value for birth weight is 2 pounds, 64 pounds weaning weight and 92 pounds yearling weight. In addition, the “keeper” Simmental bulls have an average rib-eye area EPD of .93 and marbling EPD of .16, which are both above the 50 percentile of the breed. Those Simmental breed values for rib-eye area EPD are .77 and marbling EPD of .13.
Through the years, data, particularly averages, hold true. If one bull breeds less cows, the bull has less genetic influence on next year’s calf crop. However, through time, similar bulls will breed a similar number of cows, so the genetic trends will move in the direction of the desired outcomes.
As producers, we picture the perfect cow and the perfect bull that leads to the perfect calf. That only happens in a perfect world. The best we can do is gather the data and keep our options open. It works to base selection on solid numbers. Eventually, we will arrive at a point where the calf is at least close to being perfect.
Yes, we still control the color, type, soundness and the breed. We also set the selection thresholds for the replacement bulls. That selection involves the defined genetic desires and outcomes determined through the selected genes that are going into the herd.
The selection process involving EPDs is fun, and stacking the odds is easy. EPD values impact the performance of the herd. If you want to improve the herd, improve the numbers using EPDs as the tool.
May you find all your ear tags.