Bos indicus bulls 20 months 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 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 b 0.005)
and dressing percentage (P b 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