Utilização da ultrassonografia e qualidade da carne de cordeiros Santa Inês de diferentes classes sexuais submetidos à restrição alimentar

Abstract

The objective of the present study to evaluate the use of ultrasound and quality lamb meat Santa Inês of different sex class subjected to food restriction. Were used thirty Santa Inês lambs, 15 castrated and 15 non–castrated, with approximately two months of age and initial body weight in average of 13 ± 1.49 kg. The lambs were assigned to a completely randomized design in a 3x2 factorial arrangement (levels of feed restriction x sex class), according to the amount of food provided. Experiment period was determined based in the time required for the animals one of the groups achieved 28 kg of body weight in average, when all 30 animals were slaughtered. There was no significant interaction between restriction levels and sexual class to rib eye area (REA), subcutaneous fat thickness (SFT), depth of Longissimus dorsi in the lumbar (DLDL) and thickness of subcutaneous fat in the lumbar (TSFL) at slaughter. Possibly due reduction in food supply, the REA, the SFT, the DLDL and The TSFL showed average values reduced in function increase levels of feed restriction. There was interaction between levels of feed restriction and the measurement dates to REA, SFT, DLDL and TSFL. Significant correlations were observed between the in vivo characteristics and carcass characteristics. The REA by ultrasound in vivo was highly correlated with the measure of this variable in the carcass, demonstrating its efficacy. There was interaction between levels of feed restriction and sex classs for the variables intensity of yellow and pH in Longissimus lumborum and shear force in Semimembranosus muscle. To animals non-castrated, the intensity of yellow was higher with 30% restriction on the Longissimus lumborum. There was no significant interaction between restriction levels and sexual class to quality aspects related to color saturation, color tone, luminosity, red intensity, water retention capacity and weight loss for cooking for Longissimus lumborum and Semimembranosus muscles. Santa Ines lambs subjected to food restriction have lower values for REA, SFT, DLDL and TSFL, which are valued in vivo. Although feed restriction and sexual class have influenced the variables related to the meat quality of animals evaluated, the mean values observed are considered acceptable in the literature. The food restriction levels and sexual class influenced some important features of meat quality Santa Ines lamb.