The effect of different storage temperature on sperm parameters and DNA damage in liquid stored New Zealand rabbit spermatozoa

Abstract

The effect of two different temperatures (4°C and 15°C) on motility, plasma membrane integrity, acrosome abnormality and DNA damage of rabbit spermatozoa was evaluated at 0 and 24 h of liquid storage. Ejaculates collected from six New Zealand male rabbits by artificial vagina and pooled at 37°C following evaluation. Pooled ejaculate was divided into two equal aliquots and diluted with the Tris based semen extender at a final concentration of approximately 40x106 sperms/ml in a Eppendorf plastic tube. There were no significant differences in the percentage of above mentioned parameters between 4°C or 15°C at the beginning of liquid storage (0 h). The percentages of motility (75.0±1.83%) and plasma membrane functional integrity (71.2±1.14%) at 15°C was significantly better than that of liquid stored semen at 4°C (67.9±1.01% and 65.3±1.38%, P<0.05, respectively) at 24 h of storage. The percentage of acrosome abnormality at 24 h wasn't affected by the different storage temperature. The influence of storage temperature and the length of time on spermatozoa DNA damage was found statistically significant (P<0.001). The storage period for up to 24 h lead to an increase in the percentage of spermatozoa DNA damage (P<0.001). The percentages of DNA damage at 4°C was statistically higher than 15oC (P<0.001). In conclusion, 15°C may be prefered when liquid stored rabbit semen are used for 24 h.