A more holistic approach to carcass value… Carcass Weight and Yield Grade

by Larry Keenan, Director of Breed Improvement

Advancing the mission of genetically describing Red Angus cattle for traits that have a direct impact on profitability, Red Angus has added Carcass Weight (CW) and Yield Grade (YG) EPDs to its arsenal of Economically Relevant Traits (ERTs).

Scheduled to be released along with the Spring 2011 EPDs, CW and YG EPDs will empower Red Angus Stakeholders with the tools to make genetic progress in two traits that significantly impact carcass value and feedyard profitability. The deflated choice:select spread and reduced cattle numbers have combined to refocus the industry’s selection pressure away from simply increasing Marbling Scores and looking instead to place greater selection pressure on carcass weight and lower Yield Grades.

Carcass Weight (CW): Predicts differences in hot carcass weight and is expressed in pounds.

Yield Grade (YG): Predicts differences of carcass yield grade score and is expressed in USDA Yield Grade score (1- 5).

Carcass Weight
Calculated using a multi-breed model which includes birth, weaning, and yearling weight data, RAAA’s CW EPD is not subject to culling bias; thus, provides a more reliable genetic prediction as compared to only using actual carcass weight. This computation allows for the use of weights taken on ~57,000 animals per year as compared to only ~1,500 animals per year with actual carcass weight observations.

Determining the level of selection pressure placed on CW should be a very well thought out decision, as grid pricing assigns significant discounts on carcasses that are too light (less than 550 pounds) or too heavy (over 1,000 pounds). Therefore, producers should avoid reckless maximization/ minimization of CW EPD. A more appropriate use of the CW EPD starts with knowing the previous carcass performance of a producer’s calf crop. Based on that initial information, producers can better determine the level of selection pressure for CW EPD in an effort to achieve their ideal carcass weight.

Yield Grade
Just as the USDA Yield Grade is calculated using the individual animal’s carcass weight, ribeye area (REA), and backfat (FAT) data, RAAA’s YG EPD is calculated using the genetic predictions of CW, REA and FAT EPDs. The reliability of Red Angus’ YG EPD is enhanced by using both ultrasound and actual carcass data in the calculation of REA and FAT EPDs.

Prior to the publication of YG EPD, producers who desired a change in the yield grade genetics of their cattle were hamstrung, as they were forced to utilize two indicator traits (REA and FAT) of yield grade. Through providing a YG EPD, producers are now armed with a reliable, easy to implement tool which will better enable successful selection decision.

How we got ‘em
While RAAA has long sought after the ERTs of CW and YG, the availability of these two new ERTs was made possible through Red Angus’ genetic evaluation relationship with the American Simmental Association. While we have already made one quantum leap through the ability to account for heterosis, the benefits of this relationship continues.