Abstract:
The domestication of animals has rendered horns less necessary for survival. Moreover, the use of polled and disbudded animals is interesting in order to avoid injuries of animals and handlers, among other advantages. We therefore conducted a comparative economic analysis of different traditional disbudding techniques versus selective breeding for polledness in Nelore cattle, the main beef breed of tropical systems in Brazil. The cost to obtain animals without horns was estimated in three different scenarios: disbudding with hot iron, disbudding with caustic paste, and phenotypic selection for polled animals. Price quotations of the materials were obtained in different states of the country and averaged. An initial frequency of horned animals of 92.16% was obtained based on the records of the Brazilian Association of Zebu Breeders. Selective breeding was found to be the best cost-effective scenario. This result differs from intensive production systems of dairy cattle in which traditional disbudding continues to be the best cost-effective scenario. The main explanation is the lack of difference in the price of Nelore semen from polled and horned bulls. Phenotypic selection for polled animals is the best cost-effective method, and it is in accordance with welfare practices. Care should be taken regarding the intensive use of few polled breeding animals in order to avoid inbreeding depression in other traits.
摘要:
动物的驯化使人类生存所需的角变得不那么必要。此外,为了避免动物和搬运工受伤,使用被调查和不友好的动物是很有趣的,在其他优势中。因此,我们对Nelore牛的不同传统繁殖技术与选择性繁殖进行了比较经济分析,巴西热带系统的主要牛肉品种。在三种不同的情况下,估计获得没有角的动物的成本:用热铁除名,用苛性碱膏驱散,和被调查动物的表型选择。材料的价格报价是在该国不同州获得的,并进行了平均。根据巴西Zebu育种者协会的记录,有角动物的初始频率为92.16%。发现选择性育种是最佳的成本效益方案。此结果与奶牛的集约化生产系统不同,在该系统中,传统的繁殖仍然是最佳的成本效益方案。主要的解释是,Nelore精液的价格与被投票和有角公牛的价格缺乏差异。被调查动物的表型选择是最佳的成本效益方法,这符合福利惯例。应注意大量使用少数被调查的繁殖动物,以避免其他性状的近交抑郁。