Genetic parameters of aggressiveness, ferocity and mobility in the fighting bull breed

Abstract

Genetic parameter estimates for Aggressiveness, Ferocity and Mobility in the fighting bull bovine breed were obtained using the restricted maximum likelihood (REML) methodology applied to a multiple trait animal model. The year of birth and the sex of the animal were the environmental fixed effects considered in the model. Genetic trends were determined from the average predicted breeding value over the year of birth. The behavioural traits considered showed an important additive genetic component which can be used to modulate the phenotype expression by selection. Heritability values around 0.3 (0.286-0.362) for all traits could explain the successful empirical selection carried out on the Aggressiveness trait. Similarly, the lack of genetic correlation (P > 0.05) between all traits explains the absence of a correlated response for the Ferocity and Mobility traits.