Freezing of Honamli Goat Buck Sperm with Commercial and Laboratory Extenders and Evaluation of In Vitro Spermatological Parameters

This study aimed to evaluate the effectiveness of commercial versus laboratory-made extenders for cryopreserving Honamli buck semen. Semen was collected from three 2-3-year-old bucks and pooled. The pooled semen was divided into two portions: one with seminal plasma removed and diluted with Tris egg yolk-based extender (TEYBE+), and the other with seminal plasma retained, extended with commercial Bioxcell (B), Tris egg yolk-based extender (TEYBE-), and Tris lecithin-based extender (TLEBE). The extended semen was stabilized at +4 °C for 2 hours, cryopreserved by exposure to liquid nitrogen steam at -120 °C for 12 minutes, and frozen. After thawing, motility, viability, plasma membrane and acrosome integrity (PMAI), high mitochondrial membrane potential (HMMP), and mitochondrial reactive oxygen species (MROS) levels were evaluated. Group B exhibited the lowest post-thaw motility, viability, PMAI, and HMMP values (p < 0.001). The highest viability rate was recorded in the TEYBE+ group (p < 0.05). TEYBE- showed superior motility, PMAI, HMMP, and viability compared to B, whereas TLEBE did not outperform TEYBE+. The lowest MROS levels were observed in the TEYBE+ group (p < 0.05, compared to B). In conclusion, the findings indicated that the separation of the seminal plasma used in the freezing of buck semen had a beneficial impact on the freezing process. Conversely, the B extender, which is commercially employed for freezing bull semen, was ineffective in cryopreservation of the buck semen when compared to extenders containing lecithin and egg yolk.