Effect of Extenders Including High Concentrations Dimethyl Sulfoxide (DMSO) on Post-Thaw Rabbit Sperm Parameters

Cryoprotectants have critical roles to prevent cell damages during cryopreservation. However, the adjustment of cryoprotectant concentration is also very crucial to protect cells from cryoprotectant toxicity. The present study was designed to investigate the effect of extenders including high concentration dimethyl sulfoxide (DMSO) on post-thaw rabbit sperm quality. Pooled rabbit sperm samples (n=7) were diluted and cryopreserved in extenders including 250 mmol/L Tris, 88 mmol/L citric acid, 47 mmol/L glucose, 1% sucrose and different concentrations of DMSO. The presence of high concentration DMSO (12 and 14%) in extender decreased sperm total and progressive motility (P < 0.01). The 8 and 10 percent DMSO supplementations in extender increased live sperm rates (P < 0.01). Live and intact acrosome or intact membrane sperm rates were detected higher in 8 and 10 DMSO groups (P < 0.05). When total intact membrane sperm rates were similar in all groups, total intact acrosome sperm rate was higher in 8 DMSO group compared to 12 DMSO group (P < 0.05). In conclusion, when 12 and 14 percent DMSO additions in extender adversely affected post-thaw sperm parameters, the presence of 8 percent DMSO in extender provided the highest post-thaw sperm quality.