Características de carcaça e qualidade de carne de cordeiros alimentados com silagem à base de palma forrageira e torta de algodão

Abstract

The study aimed to evaluate carcass traits, meat quality and the yield of non-carcass constituents of lambs fed complete diet silage based on spineless cactus. Thirty-two crossbred Dorper lambs with initial age of 120 days and average initial live weight of 17±1.5 kg were used. The experiment was carried out in a completely randomized design with four treatments (0, 20, 25 and 30% inclusion of cotton cake) and eight replications. Data referring to each treatment were compared using orthogonal contrasts, which when significant by Dunnett's test, were submitted to simple regression analysis at 5% probability. The biometric variables were subjected to principal component analysis, Pearson correlations and used in the development of the carcass traits prediction equation through regression analysis at 5% probability. Morphometric and biometric data were submitted to canonical discriminant analysis to identify the variables that best discriminate the treatments and build a discriminant function that represents the differences between treatments. There was no effect (P>0.05) of treatments on carcass characteristics, weight and yield of commercial cuts, weight of edible and inedible organs, tissue composition, pH, temperature, color, cooking losses, moisture and content of protein from the meat of the lambs. Among the biometric variables studied by multivariate analysis, 6 body measurements fit (P<0.05) to the prediction equations of slaughter weight, empty body weight, hot carcass weight, cold carcass weight, hot carcass yield, cold carcass yield, ribeye area and edible viscera weight, suggesting that producers who do not have a scale and want to use the experimental diet can predict meat production from biometric measurements using the equations generated in this study. The variables with greater discriminatory power between treatments, selected based on standardized canonical coefficients, were chest depth (with greater discriminatory power by the stepwise method), withers height and leg width. The first two canonical variables were sufficient to explain 73% and 20% of the total data variation. The inclusion of up to 30% cotton cake in the forage palm silage can be used in the finishing of lambs without harming the production of meat in confinement.