Effects on performance and carcass and meat quality attributes following immunocastration with the gonadotropin releasing factor vaccine Bopriva or surgical castration of Bos indicus bulls raised on pasture in Brazil

摘要

Bos indicus bulls 20 months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at dO and d91 (group IC, n = 144) or were surgically castrated on d91 (group SC, n = 144). Slaughter on d280, was 27 weeks after castration. Adverse safety issues in 8% of group SC bulls following surgery contrasted with 0% in group IC bulls. At d105 testosterone levels were suppressed to similar levels in both groups. Importantly, group IC bulls had higher live weight, hot carcass weight, ADG (P ＜ 0.005) and dressing percentage (P ＜ 0.0001) compared to group SC animals. There were no negative effects on carcass or meat quality traits, thus immunocastration was concluded to offer a safe and effective method that provides production gains, and improves animal welfare in Bos indicus beef bulls without impacting meat and carcass quality.