Características de carcaça e carne de novilhos nelore recebendo lisina e metionina na dieta

Abstract

Meat quality can be defined and measured quantitatively and qualitatively by analyzing color, texture, marbling, tenderness, subcutaneous fat thickness and loin eye area. Some equipment is used for these analyzes, such as colorimeter, texturometer, caliper, as well as evaluations by sensory panels. The objective of this study was to evaluate carcass and meat characteristics of confined Nellore cattle receiving the amino acids lysine and methionine in the diet. A total of 100 uncastrated male cattle with an average initial age of 18 months and an average initial weight of 295 kg were used. The animals were weighed and randomly assigned to three experimental groups, the lysine group, methionine-associated lysine group and the third group as control group receiving standard diet without addition of the two protected amino acids. The animals were confined for 133 days. For carcass and meat evaluations, three animals per stall were selected that corresponded to the closest to the average of each stall. The animals were slaughtered after a 24-hour fasting in a federally-inspected refrigerator. After slaughter, the carcasses were identified, halved and weighed to obtain the hot carcass weight. They were then washed and cooled in a cold chamber under forced ventilation for 24 hours. After cooling, the carcasses were weighed to obtain the cold carcass weight. Carcass conformation, morphometric measurements and subcutaneous fat thickness. Visual assessment was performed to determine the degree of marbling, texture and color after 30 minutes of removal from the cold chamber. For shear force, laboratory analyzes were performed using the device Warner Bratzler Shear Force. To evaluate the effect of treatments, analysis of variance (F test) was performed and means were compared by Tukey test (p <0.05). For the subjective variables (color, texture and marbling) we used the Kruskall-Wallis test (p <0.05). All analyzes were performed using the easyanova package of the R program. Using the amino acids lysine and methionine, it was possible to observe that there was no performance, carcass characteristics and meat quality.