Effects of sulfanilamide on boar sperm quality, bacterial composition, and fertility during liquid storage at 17°C.

Sulfanilamide (SA) is an effective broad‐spectrum antibacterial agent in human and veterinary medicine. The purpose of this study was to evaluate the effects of SA on boar sperm quality during liquid storage at 17°C and determine the optimal concentration of SA and its effects on bacterial growth, microbial composition, and maternal fertility. Boar ejaculates were diluted with a basic extender, containing different concentrations of SA, and stored in a 17°C incubator for 6 days. The sperm motility, plasma membrane integrity, and acrosome integrity were measured daily. The results showed that when the concentration of SA was 0.02 g/L, the sperm quality parameters were significantly higher than those of all other treatment groups (p < .05). We also monitored the bacterial growth and compared the differences in the microbial species between the 0.02 g/L SA group and the control by 16S rDNA sequencing. The results revealed that some bacteria, such as Staphylococcus and Pseudomonas, were considerably lower in the 0.02 g/L SA group than in the control group (p < .05). In addition, preserved semen was used for artificial insemination, and results showed that 0.02 g/L SA group had a higher litter size, and its pregnancy rate was 92.5%. [ABSTRACT FROM AUTHOR]