1Animal Science Department of Viçosa Federal University (DZO/UFV) PH Rolfs Avenue, Viçosa City, Minas Gerais, Brazil
2Veterinary Medicine Department, Anhanguera Educational Faculty of Dourados/MS
3Veterinary Department of Viçosa Federal University (DVT/UFV)
4Federal University of Espírito Santo/UFES/Alegre-ES/Brazil
This study reports a high presence (29 to 69%) of sperm segmental aplasia from mitochondrial membrane on nine sexually mature Gir breed bulls (aged from 19 to 57 months). It was not observed any kind of genital disturbance in the breeding soundness evaluation, but the microscopic exam of the semen revealed: 10 to 30% of spermatozoa had progressive motility, and sperm vigor varying from 1 to 2. Based on the knowledge of the genealogies of those animals, it was verified that they presented low inbreeding level. Based on these results and on the fact that those animals had not been fed gossypol, and were not in the prepubertal phase, it can be suggested that inheritance and diet may not be the only factors for the incidence of this injury on Gir breed males. Probably, those animals had an imperfect spermiogenesis, being discarded for reproduction.
Gir, Mitochondrial membrane, Spermatozoa
