SALEM, Ohio – Most shoppers don’t compare apples to oranges at the supermarket, yet a large number of beef breeders still compare genetic merit of bulls and cows of separate breeds without thinking twice.
To put sires and dams on a more level playing field, researchers have developed an across-breed EPD chart, a tool to help producers estimate expected progeny differences for crossbred beef animals.
EPD data has been used in beef cattle since the early 1970s. Research allowed the creation of across-breed EPD charts in 1992, and the chart is updated yearly to reflect breed differences observed in research.
Charts work. The expected progeny differences indicate the differences expected in performance of the future progeny of two parents, according to Larry Cundiff, genetics and breeding research leader at the U.S. Meat Animal Research Center in Clay Center, Neb.
The numbers are averages of several animals taken from research including university genetic evaluations, averaged at a base point of zero, he said. Factors are adjusted to an Angus base.
EPDs are done separately by each breed to reflect averages within the breed only.
“You can’t compare individuals of different breeds [without the chart] because the base point is different for each breed,” Cundiff said. “It’s like comparing apples to oranges.”
Breed example. For example, if a Gelbvieh bull has an EPD for weaning weight of +25 and a Hereford bull has an EPD of +25, we shouldn’t expect the progeny from a different breed of dam to weigh about the same.
In this case, the across-breed EPD for the Gelbvieh is 33.1 after the table adjustment factor of 8.1 is added to the bull’s own +25 EPD.
The Hereford’s balanced EPD is 25.4 after the table’s adjustment of 0.4 is added to the bull’s EPD of 25.
In this example, the progeny of the Gelbvieh bull would be expected to weigh, on average, 7.7 pounds (33.1 – 25.4) more at weaning than the progeny of the Hereford bull.
The charts currently offer comparison data for birth weight, weaning weight, yearling weight, and milking ability EPDs.
Breeds included in the 2001 chart are Hereford, Angus, Shorthorn, South Devon, Brahman, Simmental, Limousin, Charolais, Maine-Anjou, Gelbvieh, Pinzgauer, Tarentaise, Salers and Red Angus.
The 2002 chart will be released later this summer, according to Cundiff, and will feature data for the Braunvieh breed.
Crossbreeding. To remain competitive with pork and poultry, the beef cattle industry is under increasing pressure to reduce costs of production and fat while maintaining tenderness and palatability, according to a report on research done by Cundiff and Keith Gregory.
To meet those challenges, breeders are urged to take a look at crossbreeding programs or composite populations to make breed differences work for their herd.
“No one breed excels in all traits of importance to beef production,” Cundiff said.
The numbers prove that crossbreeding pays off. Research showed genetic potential for retail product yield, marbling and carcass weights are optimized more in crossbred cattle than in purebred animals.
Benefits. “There are a lot of producer benefits to using EPDs, including increasing uniformity across the herd,” Cundiff said.
Uniformity is helpful in crossbreeding systems for traits such as birth weight to manage calving difficulty, and for traits related to cow size and milk production to manage feed requirements in the cow herd.
“You can select a bull breed for calving ease. With a terminal sire with slaughter progeny, you can select for the maximum growth and size EPD,” Cundiff said.
“Producers with different objectives can use this information in different ways to get what they need,” he said.
Cundiff’s and Gregory’s research has also proven that heterosis, where offspring display greater vigor, size and resistance than their parents, can be used to increase weight of calves weaned per cow by 20 percent. Crossbred cows remain in the herd 1.3 years longer and have 30 percent greater lifetime production than purebred cows.
(You can contact Andrea Myers at 1-800-837-3419, ext. 22, or by e-mail at amyers@farmanddairy.com.)
