Sericin-Enriched Rabbit Semen Preservation: Implications for Short-Term Storage Quality and Fertility at 4 or 15°C

The influence of sericin supplementation and chilling temperatures (4°C and 15°C) on the short-term storage quality and fertility of rabbit semen was assessed over 72 hours of storage. In experiment 1, pooled semen (from five ejaculates) was diluted to a concentration of 50M ml−1, and assigned to control, 0.1% and 0.5% sericin groups, stored at 4 or 15°C. Sperm motility, sperm kinematics, viability, membrane and acrosome integrity were assessed at 0, 24, 48, and 72 hours of storage. The experiment 2 and 3 were conducted to observe effect of sericin on bacterial growth and in vivo fertility. The results of experiment 1 showed that sericin treatment, storage temperature, and storage duration influenced progressive and total motility, as well as sperm kinematics. Similar effects were observed for acrosome integrity, membrane integrity, and sperm viability. The results of experiment 2 indicated the antimicrobial effects of sericin when sperm were stored at 15C for 72 hours. While promising pregnancy outcomes were observed with sericin treated sperm for 72 hours, these results not significantly different. The study conclusively demonstrates that sericin treatment enhances the quality of rabbit semen when stored at lower temperatures for longer durations. Antimicrobial effects of sericin could be a contributing factor to the improved in-vitro and in-vivo fertility of rabbit sperm.