EPDs help producers meet goalsWritten by Gayle Smith
Spangler gave a webinar presentation on utilizing EPDs in the selection of sires to make genetic progress and meet producer’s goals. During the presentation, Spangler’s goal was to help producers understand the vast amount of information available to them, and focus on what truly benefits their operations.
“I think the first thing producers have to do is contemplate their entire breeding system and identify their breeding and marketing objectives, before they can isolate the key traits they need to select for when purchasing their bulls,” he stated.
It is important for producers to realize, “No one breed excels in all areas that lead to profitability,” he continued. “That is why in a commercial cow/calf operation, the implementation of some type of crossbreeding system, in my mind, is absolutely paramount.”
Commercial operations should take advantage of crossbreeding opportunities to capture hybrid vigor and heterosis. By capitalizing on hybrid vigor, producers can use the benefits of multiple breeds, and put that together to create a superior animal. However, he cautioned producers to use stringent selection to pick the right animals for a crossbreeding program.
Although feed efficiency is currently the buzz in the cattle business, Spangler said producers should look at a broader, global scale.
“If we can increase the number of progeny per dam through selection, heterosis from crossbreeding, or better management, we will increase the efficiency of production,” he said.
Crossbreeding is about optimizing, not maximizing genetics.
When ranchers open a bull or semen catalog, Spangler said it can be confusing to see all the data and measurements. He urges producers to focus on which traits they need to improve their cattle, and their bottom line.
“By focusing on that, it should help you to narrow it down to those sires, and then look at their EPDs,” he explained.
A look at EPDs
EPDs refer to on average, how much better is that sire’s calves compared to others within the breed.
“It is a cumulative average of how a sire is performing,” Spangler said. “The offspring of one sire exhibit more than three-quarters of the genetic diversity of the entire population,” he added. “By having the same sire, all we’re accounting for is one-quarter of the genetic variation. You can expect some differences when mating these sires among many contemporary groups.”
Spangler reminded producers that EPDs are only valuable when comparing animals within a breed. However, the U.S. Meat Animal Research Center in Clay Center, Neb. does publish annually a set of crossbred adjustment factors that will allow producers to compare the breeds to one another on an Angus basis. The traits that are comparable are birth weight, weaning weight, yearling weight, and milk. Some carcass traits are also available. This chart can be located at beefimprovement.org.
Improving the herd
Spangler cautioned producers about the genetic correlation of traits they select for. To demonstrate, he shared a chart showing how much weaning weight has increased during the last two decades.
“It is obvious that producers have selected for this trait to have more pounds to sell,” he explained. “However, immature weights have a direct correlation to mature weights. This is relevant to the cow/calf producer who sells at weaning and saves replacement heifers. He has maximized weaning weight, but has also inadvertently increased mature size of his cowherd.”
Milk production is also a trait Spangler discourages producers from focusing on too heavily.
“All breeds have a milk EPD, and some breeds have even selected for milk,” he said. “But increased milk production comes at a cost, so I would think about the consequences of selecting for milk. Select at an optimum level, not at a maximum level,” he said.
DNA technology is also improving in the beef industry. Although it has been helpful in the past resolving uncertain paternity, and identifying recessive carriers and genetic defects, it is now aiding in adding accuracy to the EPDs of young sires.
Spangler said the question becomes whether genotyped bulls, which are those with genomic-enhanced EPDs, are better.
“It does not make one bull better than another,” Spangler responded, “but it does provide the potential to make the EPDs more accurate.”
“It is important when selecting a sire, to understand the fundamentals by looking at the EPDs, and on younger bulls, look at their accuracy,” he said.
The geneticist urged producers to concentrate on traits that are economically relevant to their bottom line and understand the difference between sources of information.
“Know that EPDs and economic index values are more valuable in selecting parents for the next generation than actual records or ratios,” he explained. “EPDs are seven to nine times more effective in generating response to selection than actual measurements.”
For commercial bull buyers, the fundamentals are still in place. Look at EPDs, but realize there could be differences in EPD accuracy, he explained.
“Genomic information has the potential to increase accuracy. Multiple trait selection is critical and could become more cumbersome. Economic indexes help alleviate this if you use the index values that meet your breeding objectives,” he said.