Realimentation of Cull Range Cows. 3. Prediction of Carcass Composition

Abstract

Three separate trials were conducted with cull range beef cows to determine the effect of short-term feeding on carcass characteristics and composition. Carcass composition values by wholesale cuts and the total carcass were compared. Composition (protein, lipid, bone) of the wholesale rib or plate was highly correlated (P<.05) to composition of the entire carcass. Therefore, equations were developed to predict carcass composition utilizing compositional values from the plate or rib in conjunction with carcass cooler traits (ribeye area, fat thickness, hot carcass weight, % kidney fat). Prediction equations were formulated using the data from trial 2, and trials 2 and 3 combined. These equations were tested for accuracy using the compositional data collected for the whole carcasses of cows fed in trial 1. The paired t-test was used as a measure of predictive accuracy. Equations developed from either the plate or rib in conjunction with the carcass cooler traits were found to be accurate (R2 = .73 to .99) in predicting the carcass composition of animals on an individual basis. Therefore, these provide a valuable research tool to evaluate carcass composition of cows without reverting to laborious, tedious, expensive procedures.