Abstract Bos indicus bulls 20months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at d0 and d91 (group IC, n=144) or were surgically castrated on d91 (group SC, n=144). Slaughter on d280, was 27weeks 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.