DNA technology has the potential to help cattle producers refine their seedstock selection and to provide a more accurate look at the future feedlot or herd performance potential of their calves.
That was the upshot of a recent DNA technology briefing held for cattlemen and breed association representatives at USDA's Meat Animal Research Center at Clay Center.
Some cattlemen are already using DNA testing to identify performance criteria in their cattle or verify paternity in a multiple-bull breeding pasture. Some also use it to weed out breeding animals that carry an undesirable trait such as curly calf, the experts indicated.
That's only the beginning of what DNA testing can do for the cattle industry, according to Mark Thallman, research geneticist at MARC. Current testing looks for a few of the big traits known to have a positive economic impact on cattle production. But there are hundreds of traits with the potential to enhance or adversely impact beef production that could add up to bigger gains or losses than the few currently being targeted.
The National Beef Cattle Evaluation Consortium is a group of researchers, breed and cattle industry representatives and forward-looking producers working to bring all means of evaluating future cattle performance together to better predict genetic potential.
For many years, breed associations have computed EPDs (expected progeny differences) based on birth, weaning and yearling weights, unassisted calving and other desirable characteristics, to determine the degree to which animals of a certain pedigree can effect positive change in offspring.
But even full siblings from the same embryo flush aren't identical, said John Pollak of Cornell University, director of the National Beef Evaluation Consortium. There are 30 cattle chromosomes: A single mating can produce more than a million different genetic combinations.
If a producer knew more about which traits an individual possessed, they could make more rapid herd improvements, explained Matt Spangler, University of Nebraska beef geneticist.
For instance, a cattleman who buys a yearling bull or semen from an unproven sire bases his decision on pedigree, EPDs, appearance and possibly a little genetic marker information from the breeder. But it's nine months to a year before the first calves hit the ground, and the bull has bred a second set of cows before the first calves are grown and steer performance can be evaluated. Add another year to determine the bull's influence on the maternal abilities of his first heifers.
The Coalition's 2000 Bull Project, begun a few years ago, is looking at the traits associated with more than 2000 A.I. sires from 16 different breeds, correlating performance with genetic analysis, said Thallman. First focus will be weight traits, then carcass traits and finally performance, health, and other factors. Then the researchers will need to figure out how to merge data into a set of DNA-assisted ratings that cattlemen can use.