Evaluating the Impacts of Gender, Fatness, Muscling, and Weight on Yield Grade 4 Beef Carcasses.

This study was conducted to assess cutout and value differences in Yield Grade 4 beef carcasses by evaluating impacts of gender, fatness, muscling, and weight. USDA Choice, Yield Grade 4 carcasses (n = 60) were selected according to gender: heifers (n = 20) and steers (n = 40), and weight groups: lightweight heifers (315.5 - 362.9 kg) and steers (362.9 - 408.2 kg), and heavy weight heifers (362.9 - 408.2 kg) steers (408.2 - 453.6 kg). Within weight classes, carcasses were separated according to ribeye area per 45.36 kg of HCW ratio (REAcm2 :100 kg): heifers (>21.76) and (< or equal to 21.76); steers (greater than 20.07) and (less than or equal to 20.07) based on analysis from NBQA-2005 (National Beef Quality Audit - 2005). Data in this study showed that within yield grade 4 carcasses, there are both conformational and value differences associated with different types of yield grade 4's, particularly when sex-class is considered due to the biological differences associated with fat and muscle deposition between genders. As expected, carcasses from heifers had more trimmable fat than steers, and steers had higher yields of certain cuts from the chuck and in bone differences than did heifers. In this demonstration, applied estimated discounts out-weighted the value differences found in cutout values. There were no clear associations in carcass traits that could be used to more accurately sort value differences in Yield Grade 4 carcasses with exception to sex-class. However, the present data suggests a need to establish a prediction equation that predicts carcass value in addition to the current Yield Grade equation. In conclusion, further research is needed incorporating all yield grade carcass types. Standard carcass fabrication styles and fat trim levels consistent with industry are needed to further assign current subprimal and minor cut prices. Additional premium and discount prices are needed for a current industry representation to obtain if premiums and discounts are being applied according to potential profits or losses incurred because of cutability differences found between the different yield grades.