Cara Jaqueline Rodrigues Ferreira, de Araújo Thiago Luis Alves Campos, Néves Andrei Pereira, Latta Karla Izidio, Pereira Marília Williani Filgueira, de Oliveira Menezes Gilberto Romeiro, Feijó Gelson Luís Dias, de Nadai Bonin Gomes Marina, da Costa Gomes Rodrigo
Federal University of Mato Grosso do Sul - UFMS, College of Veterinary Medicine and Animal Science - FAMEZ, Cidade Universitária, Av. Senador Filinto Müller, 2443, Campo Grande, MS, 79070-900, Brazil.
Federal Rural University of the Semi-Arid, Mossoró, RN, 59625-900, Brazil.
Trop Anim Health Prod. 2025 Feb 19;57(2):71. doi: 10.1007/s11250-025-04319-5.
The objective of this study was to evaluate the effects of different castration methods, body weights at castration, and feeding management practices on the performance, carcass traits, and meat quality of grazing Nellore steers. 60 male cattle were randomly distributed among the following treatments: surgical castration (SC) at 350 kg body weight (BW) and finished in semiconfinement; immunocastration (ImC) at 350, 400, and 450 kg BW and finished in semiconfinement; and ImC at 450 kg BW and finished receiving protein-energy (P-E) supplementation. All steer production phases were carried out in a grazing system with tropical grass, and only the level of supplementation was varied. The animals were subsequently slaughtered, their carcasses were qualitatively and quantitatively evaluated. The measures of animal performance, carcass traits, composition, and physicochemical quality of aged and unaged meat were considered dependent variables. Immunocastration promoted greater (P < 0.05) average daily weight gains (ADG) postweaning, final BWs postweaning, final BWs at finishing, hot carcass weights, carcass lengths, and internal carcass depths. There was no effect (P > 0.05) of ImC weights on the animal performance variables; however, the ImC weight factor influenced (P < 0.05) carcass conformation and the L* component of aged and unaged meat. Semiconfinement promoted greater (P < 0.05) ADGs, final BWs, hot carcass weights, carcass yields, carcass fattening, rib eye areas, subcutaneous fat thicknesses, and L* components of aged and unaged meat. Immunocastration at 450 kg BW and semiconfinement at the finishing phase is recommended for grazing beef cattle production systems that involve the castration of males.
本研究的目的是评估不同去势方法、去势时的体重以及饲养管理方式对放牧内罗尔阉公牛的生产性能、胴体性状和肉质的影响。60头雄性牛被随机分配到以下处理组:体重350千克时进行手术去势(SC),并在半舍饲环境中育肥;体重350、400和450千克时进行免疫去势(ImC),并在半舍饲环境中育肥;体重450千克时进行免疫去势,并在育肥期接受蛋白质-能量(P-E)补充。所有阉公牛的生产阶段均在热带草原放牧系统中进行,仅补充水平有所不同。随后对动物进行屠宰,并对其胴体进行定性和定量评估。动物的生产性能、胴体性状、组成以及陈化和未陈化肉的理化品质指标被视为因变量。免疫去势促进了断奶后更高(P < 0.05)的平均日增重(ADG)、断奶后的最终体重、育肥期的最终体重、热胴体重、胴体长度和胴体内深度。免疫去势的体重对动物生产性能变量没有影响(P > 0.05);然而,免疫去势的体重因素影响了(P < 0.05)胴体形态以及陈化和未陈化肉的L成分。半舍饲促进了更高(P < 0.05)的平均日增重、最终体重、热胴体重、胴体产率、胴体育肥、肋眼面积、皮下脂肪厚度以及陈化和未陈化肉的L成分。对于涉及雄性去势的放牧肉牛生产系统,建议在体重450千克时进行免疫去势,并在育肥阶段采用半舍饲。