Cryopreservation of donkey sperm using non-permeable cryoprotectants.

This research article investigates the effects of different concentrations of sucrose and bovine serum albumin (BSA) on donkey sperm parameters after cryopreservation, comparing the effects to a control extender that contains glycerol.

Research Methodology

• The study was carried out on semen taken from five Andalusian donkeys. The semen was centrifuged and then resuspended with a commercial extender for equine sperm, with 1% BSA and varying concentrations (mol/l) of water-diluted sucrose.
• The concentrations of sucrose investigated were: 0.05, 0.1, 0.25, 0.35, and 0.45. Following this, semen from 12 more donkeys were diluted in the same base extender, containing either 0.25M sucrose (S25) or glycerol (indicated as GLY).
• The sperm was gradually cooled, put into 0.5ml straws, and then frozen in nitrogen vapors.
• The post-thaw samples were analysed for sperm motility, plasma membrane, and DNA integrity. The results were compared using ANOVA (Analysis of Variance), which is a statistical method for comparing the means of two or more groups.

Findings

• In the first experiment, it was discovered that the S25 concentration resulted in significantly higher sperm motility than the other treatments. There were no notable differences discovered in the plasma membrane or DNA integrity.
• In the second experiment, no significant differences were detected between S25 and GLY in terms of sperm motility and DNA integrity. However, S25 showed significantly higher plasma membrane integrity.

Conclusion

• The authors concluded that the extender with a 0.25M concentration of sucrose, mixed with BSA, serves as a viable alternative to traditional extenders that contain glycerol. This is useful for the cryopreservation of donkey sperm. Cryopreservation is a process where cells, whole tissues, or any other substances susceptible to damage caused by chemical reactivity or time are preserved by cooling to very low temperatures.