Effect of castration and vitamin E supplementation on carcass and meat quality of Santa Inês lambs

Abstract

Background: Carcass and sheep meat quality are influenced by several factors, such as race, age, slaughter weight, type of diet, and dietary supplementation. Objective: To evaluate the effect of castration and vitamin E supplementation on performance, carcass characteristics and meat of lambs slaughtered at 45 kg. Methods: Thirty-two male lambs (16 castrated and 16 not castrated) were fed diets with or without the inclusion of vitamin E. The animals had an average age of 180 ± 20 days and a mean weight of 25.1 ± 4.6 kg. Performance was evaluated for 56 days, and the animals were slaughtered when reaching a weight of 45 kg. The experimental design was randomized blocks based on initial weights, and variables were assessed by a 2x2 factorial design (castrated and intact, supplemented or not with vitamin E, with a probability of 5%). Results: Higher proportion (p<0.05) of visceral fat was found in castrated animals (kidney: 2.45%, inguinal: 0.57% and omental: 4.96%) than in intact animals (kidney: 1.25%, inguinal 0.27%. and omental 3.12%). The aged meat samples showed no color differences for any of the treatments, but there were differences in shear force for steaks aged for 7 days, where the castrated animals showed an average of 2.64 kgf and intact animals showed an average 3.29 kgf. The animals supplemented with vitamin E had lower shear forces in non-aged samples. Conclusion: Castration increased deposition of visceral and fat coverage but did not influence the cut yields and total carcass yield. The animals supplemented with vitamin E had lower shear forces in non-aged samples.