REPRODUCTIVE FUNCTIONALITY OF BULLS FROM THREE CREOLE BREEDS BY SEMINAL EVALUATION OF FRESH, FROZEN, AND POST-THAW SEMEN

Resumen

Creole cattle are an important zoogenetic resource that has been historically overlooked and marginalized. Consequently, their conservation is vital for preserving genetic biodiversity. The objective of this study was to evaluate the reproductive functionality of bulls from three Creole breeds through the seminal analysis of fresh, frozen, and post-thaw semen. Semen was collected using an artificial vagina from 60 bulls belonging to the Rodeo Creole, Longhorn, and Senepol breeds. The evaluated characteristics in fresh semen included body weight (BW), scrotal circumference (SCi), ejaculate volume (EV), sperm concentration (SCo), mass sperm motility (MSM), individual sperm motility (ISM), pH, viability, and total abnormal sperm (TA). In addition, semen straws were frozen, and the post-thaw individual sperm motility (PISM) was evaluated. Senepol bulls exhibited higher BW, SCi, and PISM, as well as lower TA (567.3 kg, 35.95 cm, 64.90% and 8.8%, respectively) compared to Rodeo Creole and Longhorn bulls. SCo and sperm viability were similar between Senepol and Longhorn bulls (P>0.05). No significant differences were found among the three Creole breeds for EV and MSM. BW and pH were significantly correlated (P<0.05) with sperm viability and TA percentage; SCi was correlated with EV; MSM with ISM, viability, pH and TA; and ISM was correlated with viability, TA and PISM. Additionally, sperm viability was correlated with both TA and PISM, and TA was also correlated with PISM. In conclusion, the quality parameters of fresh semen in these Creole bulls fall within the established reference values for the bovine species. Therefore, their semen can be cryopreserved for conservation and genetic dissemination purposes