title: 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.
abstract: 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<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.
authors.affiliation: Zoetis, Parkville, Victoria, Australia. sue.amatayakul-chantler@zoetis.com
authors.forename: S
authors.initials: S
authors.lastname: Amatayakul-Chantler
authors.forename: F
authors.initials: F
authors.lastname: Hoe
authors.forename: J A
authors.initials: JA
authors.lastname: Jackson
authors.forename: R O
authors.initials: RO
authors.lastname: Roca
authors.forename: J E
authors.initials: JE
authors.lastname: Stegner
authors.forename: V
authors.initials: V
authors.lastname: King
authors.forename: R
authors.initials: R
authors.lastname: Howard
authors.forename: E
authors.initials: E
authors.lastname: Lopez
authors.forename: J
authors.initials: J
authors.lastname: Walker
mesh_terms: D000818:Animals; D001835:Body Weight; D001938:Brazil; D002417:Cattle / Q000254:growth & development; D063427:Food Quality; D007987:Gonadotropin-Releasing Hormone / Q000276:immunology*; D008297:Male; D008460:Meat / Q000592:standards*; D009919:Orchiectomy / Q000379:methods / Q000662:veterinary*; D013737:Testis / Q000254:growth & development / Q000276:immunology; D013739:Testosterone / Q000097:blood; D014611:Vaccination / Q000662:veterinary; D014612:Vaccines / Q000276:immunology*
chemical_list: D014612:Vaccines; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone