Seminal plasma protein profiles based on molecular weight as biomarkers of sperm fertility in horned and polled Bali bulls.

Abstract

Background and aim: Seminal plasma proteins (SPPs) significantly influence sperm quality, playing a critical role in fertility. This study aims to investigate the molecular weight (MW) profiles of SPPs in horned and polled Bali bulls and their correlation with sperm quality parameters.

Materials and methods: Semen samples were collected from six Bali bulls (3 horned, 3 polled). Sperm quality was evaluated based on motility, viability, abnormalities, intact membranes, and acrosomes. SPPs were extracted and analyzed using one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine protein MWs. Pearson's correlation was used to analyze relationships between MW profiles and sperm quality metrics.

Results: SPPs were identified across a MW range of 15-165 kDa, with specific proteins showing strong correlations with sperm quality. Proteins at 50 and 46 kDa positively correlated with motility (r = -0.96), viability (r = -0.99), and intact membranes (r = -0.86). Conversely, proteins at 40 kDa negatively correlated with these parameters. A 25 kDa protein displayed a positive correlation with intact acrosomes (r = -0.93) and a negative correlation with abnormalities (r = -0.99). Differences in sperm quality metrics between horned and polled bulls were observed, with polled bulls exhibiting fewer abnormalities.

Conclusion: This study highlights the potential of SPP MW profiles as biomarkers of sperm quality in Bali bulls. Proteins at 50, 46, and 25 kDa are promising markers for sperm motility, viability, and intact acrosomes, respectively. These findings could inform bull selection and reproductive management strategies. Further research is recommended to validate these biomarkers using advanced proteomic approaches.