Updated results of an ongoing research project from Gardner Angus Ranch shows how breeding typical “Southern” cows with high-quality Angus sires can significantly improve the performance and carcass value of their progeny in a single generation.
The Southern Carcass Improvement Project is collaboration with Gardiner Angus Ranch, Kansas State University and Virginia Tech, to determine how much carcass improvement can be made in one generation, using high carcass value Angus AI bulls on typical Southern-origin beef cows, representing typical Bos indicus-influenced genetics most often found in Southern states.
The group purchased 22 typical southern cows from Georgia, Mississippi and Texas to serve as donors, and flushed the first set of embryos in July 2009. For the control group, the researchers used semen from 9 representative “southern” AI bulls, all from Bos indicus-influenced breeds. For the treatment group, they selected three proven Angus AI sires, chosen for high growth, muscling ability and marbling potential. They randomly selected bulls from the two sire groups for each mating.
The first set of calves was born during April and May of 2010. They spent the summer grazing at Gardner Angus Ranch in Kansas, were weaned in November and backgrounded on wheat pasture until April 2011 when they shipped to Triangle H Feedyard, Garden City, Kan. The 57 calves went to slaughter in two groups at the end of June and July. The slaughter group included 35 Angus-sired calves and 22 “southern-sired” calves. Of the donor cows in the study, six had progeny from both Angus and southern bulls, allowing direct comparisons of the sires’ contribution to calf performance and value.
For more detailed background and earlier results, read “Quick Fix” from Drovers/CattleNetwork.
Gardner Angus recently released carcass results from the progeny groups that went to slaughter this summer. All the Angus-sired and Southern-sired calves went to slaughter at the same age, rather than at weight or backfat endpoints. So some of the lighter, lower-value animals could have finished at heavier weights and perhaps better Quality Grades with longer time on feed, but they also would have incurred higher feed costs.
The results show considerable differences. While USDA Yield Grades were similar for both groups, two-thirds of the Angus-sired calves graded Choice, while none of the Southern-sired calves graded higher than Select. On average, the Angus-sired group finished with 103 points higher marbling scores, ribeye areas that were 0.96 square inches larger, 0.12 inches more backfat and 61 pounds heavier carcass weights compared with the Southern-sired group. These differences added up to an average carcass-value advantage of $134 per head for the Angus-sired group. The Angus-sired calves had higher feed intake in the feedyard, resulting in $41.31 higher average feeding costs, so the net economic advantage averaged $92.72 per head.