The American Angus Association has made enhancements to the Angus Herd Improvement Records (AHIR) program for weaning weights by expanding the age window to now include calves as young as 120 days, while also adopting a new formula for adjusting 205-day weights, according to a press release.
The change will benefit producers moving to earlier weaning programs and was effective on June 8.
For genetic evaluation and contemporary group ratios, weaning weights are standardized to a calf age of 205 days and a mature dam equivalent. Previously, only weaning weights from a range of 160 to 280 days were adjusted to 205-day weights and included in the American Angus Association National Cattle Evaluation (NCE). As a result, calves weaned earlier than 160 days of age did not receive the 205-day adjusted weights, and their data did not contribute to genetic predictions.
"Lowering the minimum age requirement for taking weaning weights will provide breeders more flexibility for taking these measurements, permitting younger calves to remain in their respective contemporary groups to better fit the management system that may be in place," says Bill Bowman, director of performance programs for the Association.
In addition, the new nonlinear adjustment formula performs a more reliable job of the calculation of adjusted weights on the calves that are on the outer bounds of the age windows.
The enhanced 205-day adjustment procedures will expand the data used in the NCE calculations to further characterize the genetic potential of the Angus breed. The American Angus Association processed a total of 283,816 weaning weights in Fiscal Year 2002. The Association, with headquarters in St. Joseph, MO, provides services to more than 35,000 members and thousands of commercial beef producers across the United States.