Avaliação da expressão de genes candidatos à qualidade da carne de ovinos pantaneiros abatidos com diferentes categorias de peso

Abstract

The carcass traits and the meat quality include a complex network of gene expression. Among these, we can highlight the GDF-8 (Growth Differentiation Factor 8) gene associated with myoblast proliferation and muscle fiber formation and the PPARγ gene (Peroxisome Proliferator Activated Receptor γ) related to lipogenesis, adipogenesis and oxidation of fatty acids. In this context, the objective of the study was to evaluate the expression of these genes in the Longissimus muscle of Pantaneiros sheep and the correlation with carcass characteristics and performance. For this, samples of the Longissimus muscle were used for expression analysis by means of RT-qPCR in nine Pantaneiros lambs. There was no correlation between the different slaughter weights with both genes studied. This fact may be related to reduced sample size. However, it was possible to verify that there were variations of gene expression between different weights. There was no significant correlation of GDF-8 gene for carcass and performance characteristics. However, the PPARγ expression exhibited positive correlation for the marbling, texture characteristics evaluated in the Longissimus and pH of the Gluteobiceps, Triceps brachii, Semimembranosus and Longissimus muscles, and a negative correlation for feed conversion ratios and protein efficiency. There was a correlation between the increase in the expression of the PPARγ gene with amount of marbling, characteristic related to the succulence of the meat. Therefore, the results exhibit the potential of application of the PPARγ marker in the Pantaneiro sheep selection for the qualitative characteristics of meat.