Effect of different concentrations of inulin on ram sperm quality during cryopreservation

BACKGROUND: In reproductive biotechnology, sperm cryopreservation has a vital role to play. Cryopreservation of sperm produces reactive oxygen species (ROS), which disrupt sperm function and structural competence. Numerous protective chemicals, including fructans, have been used during sperm cryopreservation. OBJECTIVES: To evaluate the effect of different concentrations of the fructosan inulin on ram sperm quality parameters, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) production after freezing and thawing. MATERIALS AND METHODS: The pooled samples from four healthy rams were divided into seven equal aliquots and diluted in a Tris-base extender supplemented with 1, 2, 4, 8, 16, and 28 mM of inulin or without inulin supplementation (control). By using liquid nitrogen vapor, the semen was frozen and stored at 196°C. RESULTS: The total motility, viability, and DNA integrity were significantly improved after freezet-hawing with 28 mM inulin, compared to other treatment groups (P<0.05). A Tris-based extender containing 16 and 28 mM of inulin displayed the highest levels of ram sperm membrane integrity when compared with the control (p<0.05). The abnormality of ram sperm was increased during freeze-thawing at control and 1 mM of inulin, compared to 16 and 28 mM of inulin (P<0.05). Additionally, 28 mM of inulin decreased MDA and increased SOD activity in ram sperm in comparison with the other treatments (P<0.05). CONCLUSION: As a result, 28 mM of inulin could be beneficial for the cryopreservation industry and reduce the harmful effects of freeze-thawing on ram sperm.