The effect of adding pyridoxine to soybean lecithin-based extender on goat semen quality parameters after the freeze-thawing process

Background: Supplementing the semen extender with various antioxidants can increase the quality of semen. Aims: The aim of the present study was to investigate the addition of pyridoxine (vitamin B-6), a phenolic compound with antioxidant properties, to soybean lecithin extender on motility and quality indices of goat sperm after freezing-thawing process. Methods: Semen was collected at weekly intervals from four Mahabadi goats, mixed, and was divided into 7 subsamples. They were then diluted with the basal extender supplemented with 0, 2, 4, 6, 8, 10, and 12 mM pyridoxine. Following freeze-thawing process, quality parameters such as sperm motility characteristics, viability, plasma membrane integrity, and malondialdehyde content were determined. Results: The results showed that pyridoxine at the level of 6 mM caused the highest total motility rate (P<0.05). Progressive sperm motility was highest at the 4, 6, and 8 mM pyridoxine (P<0.05). Although the control group showed the least progressive motility, it was not statistically significantly different from the 12 mM level. Among the pyridoxine levels, the 6 mM level recorded the best performance in term of plasma membrane integrity, sperm viability, and decreasing malondialdehyde concentration compared to the control group (P<0.05). Conclusion: The findings indicated that soybean lecithin extender supplemented with 6 mM pyridoxine can improve motility and quality parameters such as viability, plasma membrane integrity, and reduce oxidative stress of goat sperm after thawing.