Effect of carboxylated ε -poly-L-lysine (CPLL)on short-term storage of ram sperm

Objective: This study was conducted to investigate the effects of adding CPLL to ram semen during short-term storage at 4°C. Materials and Methods: The study was carried out between January 2023 and February 2023 using semen collected from seven Kıvırcık rams at the Adnan Menderes University Veterinary Faculty Farm. The diluted semen was divided into three groups: the first group was designated as the control, while 0.05 g of CPLL (0.5%) and 0.1 g of CPLL (1%) were added to the two experimental groups, respectively. The semen samples were stored at 4°C. Spermatological quality parameters of both control and experimental groups were evaluated at four different time points (0, 3, 6, and 24 hours). Post-hoc Tukey test was applied for statistical analysis of the data. For each group, the mean and standard error (mean ± SEM) of the parameters were calculated and reported accordingly throughout the study. Result: It was determined that the addition of CPLL did not have a statistically significant effect on any of the examined parameters (P > 0.05). This result suggests that CPLL, a synthetic antifreeze protein analogue, may be more effective in cryopreservation rather than in short-term storage. Conclusion: It was concluded that CPLL does not provide a notable protective effect for ram semen during 24-hour short-term storage at 4°C (P > 0.05). Keywords: CPLL, ram, short-term storage, spermatological parameters