Validation of the 9–11th rib cut to estimate the chemical composition of the dressed carcass and of the whole empty body of Zebu cattle

Abstract

This study was conducted to validate the 9–11th rib cut to estimate the chemical composition of the carcass and of the empty body weight (EBW) of Zebu cattle. Nineteen Zebu steers with initial body weight of 266.5±32.2 kg were used. Four steers were slaughtered at the beginning to compose the reference group; three were fed at maintenance level, and the remaining were allotted to different planes of nutrition (5.0%, 35.0% and 65.0% concentrate levels in the diets, DM basis). The 9–11th rib cuts and half of the carcasses were dissected and the weights of fat, muscle and bone tissue were recorded. The components fat, muscle and bone tissue from the 9–11th rib cut and from the half carcass were sampled and chemical analysis of fat, protein, water, ash and minerals determined. The 9–11th rib cut satisfactorily estimated the physical composition of the carcass, but not the chemical composition. The 9–11th rib cut appropriately estimated the chemical composition of the carcass in terms of protein, water, ash and macro mineral content. For the percentage of fat and Ca, an over- and underestimation of 7.84% and 13.34%, respectively, were detected. Regression equations were fitted to estimate the percentage of fat and Ca in the carcass, and that of protein, water and ash in the whole empty body.