P-143: Effects of In Vitro Copper Supplementation on The Ejaculated Semen Parameters in Water Buffaloes (Bubalus Bubalis)

Background: A number of studies have demonstrated membrane lipid peroxidation (LPO) as one of the causes of defective sperm function in liquid semen preserved at 4◦C and cryopreserved semen. Some attempt has been made to preserve sperm parameters, particularly sperm motility, by adding some elements and Materials to the semen before freezing. Materials and Methods: To investigate effects of copper (Cu) additive to semen extenders on sperm parameters (motility, viability, membrane integrity and DNA fragmentation) after semen dilution and cryopreservation, semen samples of 5 buffalo bulls of 2-4 years old was collected at 5 different occasions during the autumn 2011. A number of 25 samples were used in each examination. Sperm motility and viability were measured before and at 0 (T0), 60 (T1) and 120 (T2) minutes after diluting semen in tris extender containing 0 (control), 0.004, 0.008, 0.016, 0.032 and 0.064 mg/L copper sulphate. A tris-egg yolk-glycerol extender containing the same amounts of copper sulphate was prepared, semen diluted, cooled to 4°C and kept refrigerated for 4 hours to equilibrate, sperm motility, viability, membrane integrity and DNA fragmentation were estimated, then, semen was packed in 0.5 ml French straws and frozen in liquid nitrogen. Later, the frozen semen was thawed in 37 °C water bath for 30 seconds, and the same parameters as well as total anteioxidant capacity (TAC) of the frozen-thawed semen were estimated. Results: The results showed that copper additive at the rate of 0.032 mg/L gives a better protection of sperms through the process of dilution, equilibration and freezethawing than that in control and other Cu concentrations. Conclusion: Our findings show that copper supplementation of semen extenders seems to be a promising procedure for preserving spermatozoa quality, motility in particular, during cryopreservation processes.