Comportamento sexual de machos nelore submetidos ao bloqueio do órgão vomeronasal

Sexual behavior of Nellore males subjected to vomeronasal organ blockade

Abstract

This study aimed to evaluate the sexual behavior and its correlations with serum testosterone concentrations and height of the vomeronasal organ (VNO) sensitive epithelium in Nellore males, extensively raised and submitted to VNO blockage in prepuberty. Forty-five animals were used: G1-control animals, integers (n = 15), G2-animals with bilaterally cauterized incisor ducts, blocked (n = 15) and G3-animals bilaterally orchiepididectomized, castrated (n = 15). The animals were evaluated every three months until sexual maturity, five tests of libido and blood collection totalizing. Animals with 480 kg were slaughtered, where the VNO were obtained for histological evaluation. The experimental design was entirely random. In fourth test, there was increased in the attempt to mount, complete mount and libido score in the integers (P<0.05). In fifth test, there was increased in smelling and licking and reduction in the flehmen reflex in the blocked and castrated (P<0.05). There was a high association between the flehmen reflex (FR) and height of the VNO sensitive epithelium in the blocked (r=0.75; P=0.05). It was concluded that the entry of olfactory stimuli in VNO is influenced by FR and this organ plays an important role in sexual behavior in Nellore males.