A Caliper for Determining Carcass Composition in Live Cattle and Skin-on Carcasses

摘要

A Harpenden Skinfold Caliper used to predict body density in man was modified for use in cattle. It nwas used to measure thickness of the anal fold, caudal fold and rectal wall in 34 live steers or their skin- non carcasses (hot dressed weight 139-339 kg). The value of these measurements in determining carcass nfat and carcass muscle was compared with that of 10th and 12th rib fat thickness measurements made nin the carcass. nHot carcass weight was the best predictor of side fat weight and side muscle weight. Side fat npercentage and side muscle percentage were most accurately predicted by 12th rib and 10th rib fat nthickness, followed by live then single-shackle anal fold fat thickness. The three caudal fold nmeasurements and rectal wall thickness were poor predictors. nAddition of hot carcass weight to all linear measurements markedly improved the prediction of side nfat weight and side muscle weight, but nor side fat percentage and, only marginally, side muscle npercentage. Single-shackle anal fold fat thickness, slightly less accurate than the live measurement, was nthe most useful skin-on measurement. nThe spring-operated caliper described can be used to determine carcass fatness and carcass lean in nlive steers with an accuracy closely approaching that of 12th rib fat thickness in the carcass.