Boneless yield of carcass of feedlot-finished young Bos indicus L. bulls

摘要

The aim of this study was to evaluate the boneless yield of the carcass of 64 feedlot-finished young Nellore bulls fed diets containing coated or uncoated urea and slaughtered at five body weights (350, 455, 485, 555, and 580 kg). A completely randomized design with a 5 χ 2 factorial arrangement was used. No significant effect was detected for the interaction between slaughter weight and diet; therefore, the variables were analyzed separately, compared by polynomial contrasts and the F test, respectively. The absolute weights of the primal cuts from the fore- and hind-quarter increased linearly as the slaughter weight of the animals increased. Increasing slaughter weights elevated the percentage of rump cap in the pistola hindquarter as well as its yield. The percentages of the rump cap and rump skirt increased linearly, whereas those of knuckle, tenderloin, flank steak, rump, and outside flat decreased and the sum of prime cuts had a quadratic effect in relation to the weight of the right 1/2 carcass. Increasing slaughter weights led to a higher percentage of fat from the trimming of the hindquarter cuts relative to the weight of the 1/2 carcass. The weight of meat cuts was similar between the groups of animals fed coated and uncoated urea. Higher slaughter weights generate heavier meat cuts but lower percentages of primal cuts from the pistola hindquarter relative to the carcass weight.