Factorial and discriminant analysis on non-carcass components of Berganês lambs from different sexual classes and crossbreeding

Abstract

AbstractThe aim of this study was to evaluate the non-carcass components (NCC) of Berganês ecotype lambs of different sexual classes and genotypes using univariate and multivariate statistics, carrying out two experimental trials. In order to evaluate the effects of the sexual class, non-castrated males (BNC), castrated males (BC) and females (BF) of Berganês ecotype lambs were used, with mean initial body weight of 27 ± 3.1 kg. To evaluate crossbreeding, non-castrated male lambs of the genotypes Berganês (BG), Berganês × Santa Inês (BSI) and Berganês × Dorper (BD) were used, as well as the control Dorper × Santa Inês (DSI), all with mean initial body weight of 28 ± 3.8 kg. The weight and yield of the total by-products was higher for BNC. Regarding the genotype, BSI showed higher weight and yield of internal fat, but the weight and yield of the total by-products was higher for BG and BD. In factorial analysis (FA), the NCC, more correlated with empty body weight (EBW) and total weight gain (TWG), showed higher eigenvectors for factor 1. For factor 2, the weights and yields of internal fat and total viscera obtained higher eigenvectors. The discriminant analysis (DA) classified 100% of individuals in their respective sexes and genotypes. Therefore, the FA indicated that, among the NCC evaluated, the weights of liver, kidneys, GIT, skin and feets are determinant for obtaining EBW and TWG. The classification achieved by the DA indicates that the sexual classes and genotypes are heterogeneous.