Last week, we analyzed weaning weights on the LiveWiRED project calves. Upon evaluating these weights, we found a positive relationship between Weaning Weight EPD of the sire and the performance of their calves (calves by sires with higher Weaning Weight EPDs weaned heavier). As yet another part of this project, DNA samples were collected on the calves, and both GeneSeek Igenity Gold and Zoetis PredicGen DNA tests were conducted. Every animal in the project was evaluated with these two different DNA tests.
Ribeye Area. As more traits and DNA scores were evaluated, the general trend of EPDs proving accurate continued. Calves by the three high-growth/high-carcass sires averaged a score of 5.42 for Igenity ribeye area (REA) on a 1-10 scale, with 10 being the highest achievable score and indicating genetics capable of producing a larger ribeye. Progeny by the two low-growth sires averaged a lower REA score of 4.0. While performing appropriate statistical comparisons, an impressive p-value of 0.00001 was found (p<0.01). This result allows us to be over 99 percent confident in saying there is a significant and measurable difference in ribeye area DNA scores between the high-growth/high-carcass sired calves versus low-growth/low-carcass sired calves. This difference is very visible in the graph noted below. These genetic differences will undoubtedly show up in our final carcass results when the cattle are harvested.
Marbling. Moving on to the trait of marbling, the Zoetis PredicGen DNA test also shows impressive Marbling DNA score differentiation between the sire groups. After performing basic statistical analysis on the data, a p-value of 0.0025 (p<0.01) was found. This once again, allows us to be over 99 percent confident that a real difference exists between the calves by the high-growth/high-carcass sires versus those by the low-growth sires in terms of Marbling scores from this DNA test. See details in the chart below.
The value of DNA testing in the LiveWiRED project is their unbiased evaluation on the expected performance of the progeny. DNA results provide positive reassurance that the EPDs are correctly measuring the performance of the sires and their progeny. The two DNA test results discussed above are great examples of how EPDs can be both verified and improved through genomic testing. There’s no question that EPDs are being made more accurate by the incorporation of DNA technology. This process aids ranchers in making more effective bull purchasing and mating decisions to more effectively achieve herd improvement, the ultimate goal of the Red Angus breed and the beef industry.
Thank you to the Red Angus Foundation Inc. for sponsoring the LiveWiRED Project!