Efecto de hembras estrogenizadas sobre el comportamiento sexual y la calidad seminal del carnero

The sexual behavior of the ram is influenced by various motivations that affect its conduct, with hormones playing a crucial role in stimulating this behavior and directly impacting the animals' reproductive performance. In reproductive programs, it is common to use animals as dummies for semen collection. However, since this is a conditioned behavior, the effects of hormonal stimuli on semen quality are often overlooked. This study aimed to compare the effect of estrogenized versus non-estrogenized females by evaluating sperm quality, behavior, and testosterone levels in three rams over 15 matings within a two-month period. The findings revealed that the presence of an estrogenized female increased semen volume by 0.5 mL (p = 0.037), improved viability as assessed by the Eosin-Nigrosin test (p = 0.010), reduced the number of immotile spermatozoa (p = 0.013), and enhanced the STR index (p = 0.019) as well as the LIN index (p = 0.13), both of which are associated with sperm motility efficiency. Although the increase in testosterone levels and observable behavioral changes was not statistically significant, the improvement in sperm quality justifies the use of estrogenized females to enhance the qualitative parameters of ovine semen.