considerações acadêmicas sobre seleção para mocho versus amochamento em bovinos em bovinos de corte

Abstract

Horns are closely related to the survival and behavior of animals in the wild, being a naturally selected recessive trait. The domestication of animals and insertion in the production systems made the horns less necessary, making it interesting to work with polled and disbudded animals for a number of reasons. The main methods of disbudding young animals are: hot iron (cauterization), amputation (cutting instruments), and chemical (caustic paste). The aim of the study was to execute comparative economic analysis between different disbudding techniques versus selection for polled Nelore cattle. Three scenarios were simulated to obtain animals without horns: hot iron disbudding (1), caustic paste disbudding (2) and phenotypic selection for polled (3) and their costs were evaluated. The costs of the materials were collected in different states of Brazil and the average values used. Based on data recorded by the Brazilian Association of Zebu Breeders (ABCZ), the initial frequency of 92.16% was obtained for horned Nelore cattle. The phenotypic selection for polled cattle was the technique with lowest cost. This result differs from intensive dairy cattle production systems in which disbudding is still the lowest cost technique. The main explanation for this is that the price of semen from polled and horned bulls does not differ in the Nelore cattle. The phenotypic selection to obtain polled cattle is also in agreement with animal welfare handling and it has the potential to access more conscious and demanding markets. Care should be taken with intensive use of few polled bulls in order to avoid inbreeding depression for other traits.