Effect of daily semen centrifugation and resuspension on the longevity of equine sperm quality following cooled storage.

The research aims to investigate if the quality of cooled horse semen could be prolonged by undertaking daily centrifugation and resuspension in fresh extender. The study found that this method might be effective in enhancing the longevity of sperm.

Methodology

• The experiment employed various semen treatments including SP10NC and SP50NC, which consisted of 10 and 50% seminal plasma, respectively, and were not centrifuged. They were instead stored at temperatures between 4-7°C for 96 hours.
• Treatments SP10C and SP50C also contained 10 and 50% seminal plasma, respectively, but were centrifuged after 24, 48, and 72 hours of cool storage. This was followed by resuspension in a fresh extender having 10% seminal plasma.

Results

• Observations noted a reduction in total sperm motility (TMOT) and progressively motile (PMOT) in the SP50NC treatment following 24, 48, 72, and 96 hours of storage.
• The TMOT did not show significant differences in the SP10C, SP50C, SP10NC groups after the same storage periods, essentially indicating that centrifugation did not negatively affect the sperm motility in comparison to non-centrifuged sperm.
• There were no differences in the COMP-(αt) percentage between treatments at any time period.
• The percentage of membrane intact sperm (SMI) was noted to be lower in SP50NC when compared with SP10C at 48, 72, and 96 hours. This suggests that centrifugation may help in preserving the cell membrane of the sperm.

Conclusion

• When sperm exposed to 50% seminal plasma for the first 24 hours was subjected to daily centrifugation and resuspension (SP50C), it yielded results similar to the SP10NC and SP10C groups after 96 hours of storage in regards to TMOT, PMOT, VCL, SMI, % COMP-(αt).
• Overall, the researchers concluded that daily centrifugation and resuspension of cool-stored horse semen in fresh extender might be a viable method to increase sperm longevity.