Effect of vitamin A restriction on performance and meat quality in finishing Holstein bulls and steers

Abstract

Twenty-four Holstein steers and 23 Holstein bulls (initial body weight= 252 ± 3.5 kg and age= 187 ± 7.5d) were randomly allocated to 4 treatments arranged in a 2 × 2 factorial design with gender (bulls vs steers) and vitamin A supplementation (either restricted at 1.3 × 1000 IU/kg, VAR, or supplemented at 4.6 × 1000 IU/kg, CTR) to evaluate the effect of vitamin A restriction on performance, carcass and meat quality traits of Holstein steers and bulls. Intramuscular fat was less (P<0.01) in bulls than in steers, and tended (P=0.09) to be greater in VAR than in CTR animals. Oxidative stability tended (P=0.09) to be greater in meat from VAR than from CTR animals at 21 d of ageing. Vitamin A restriction in Holstein bulls does not achieve the same intramuscular fat levels obtained with castration.