CMP: Meeting consumer demands through genetic selection


Dan Moser, Kansas State University animal scientist, gives a report on the final results from the NCBA Carcass Merit Project. Moser, a member of the CMP team, said the project has produced a large, multi-breed database of phenotypic information and DNA samples — an important resource in the genetic improvement of carcass merit in beef cattle.
Results of the Carcass Merit Project (CMP) conducted by the National Cattlemen’s Beef Association (NCBA) hold promise for beef producers, Dan Moser, Kansas State University animal scientist and member of the CMP team said during the 2004 Beef Improvement Federation (BIF) research symposium Thursday, May 27.

Moser gave a report on the results of the NCBA project, which was initiated in 1998 and completed just this year. The study was meant to collect data for calculating EPDs for tenderness and other carcass traits, as well as to validate previously identified genetic markers for such traits.

As Moser explained, 13 leading beef breed associations representing 14 breeds participated in the study, providing more than 8,500 progeny of sires chosen to represent the respective breeds. Each association coordinated sire selection, progeny testing, synchronization and breeding, collecting blood samples, selecting feedlots and setting the feedlot regimen, and designating harvest end points.

Cattle in the project were fed in commercial feedlots. DNA was sampled at first processing, and the animals were harvested in commercial packing facilities. After harvest, carcass data was collected and steaks were sent to the meat laboratory at K-State, where more than 7,000 progeny were tested for Warner-Bratzler shear force (WBS) values — 2,400 of which were also evaluated by a sensory panel.

“The project was designed to … allow comparison of sires within each breed, but not sires across breeds,” Moser cautioned. “The average shear force of each breed in this study is as much the result of management as it is genetics … We need to recognize that there shouldn’t be any claims of superiority coming out of this study.”

Carcass traits were representative of accepted industry standards; however, shear force values were somewhat surprising, he reported.

“What I did not expect was how high the shear force was. Before the study, a shear force over 10 pounds (lb.) was thought to be objectionable,” he said. For the CMP, researchers used 11 lb. as the threshold for acceptability, corresponding to sensory panel results. Moser reported 26% exceeded the 11-lb. threshold, and 20% were rated less than slightly tender by the sensory panel.

“It’s alarming that one-quarter of cattle were objectionable in this study for tenderness,” he said. “And these are your best genetics, managed optimally.”

Besides measuring shear force values, the study also evaluated DNA markers, characterizing 11 quantitative trait loci (QTL) for carcass and meat quality traits in each breed — identifying markers that affect, or are believed to affect, traits like fat thickness, marbling, ribeye area and others. According to study results, several QTL were found to have significant effects on shear force values and tenderness (visit www.beef.org for more information).

Overall, Moser said the research project helped promote cooperation among breed associations; raise awareness and visibility of marker-assisted selection; and develop a large, mutli-breed database of DNA (genotypes) and phenotypes.

The greatest benefit of the CMP, he said, is the creation of a legacy that will benefit the industry, helping it meet consumer demands for many years to come.

The final results of the project, which was funded by participating breed associations and the $1-per-head beef checkoff, are now available online at www.beef.org.
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– by Crystal Albers