Effect of polyols and lipids on buffalo spermatozoal survival at 5 degrees C and -196 degrees C

Six semen samples were obtained from each of the four healthy Murrah buffalo bulls and preserved at 5 degrees C up to 72 h in EYC diluter treated with glycerol (5, 7, 9 and 11%), mannitol (0.5, 1.5 and 3%), sorbitol (1, 2 and 4%), lecithin (1, 2 and 3%) and cholesterol (0.5, 1 and 2.5%). EYC diluter with semen (1:20) was kept as control. Individual motility of the spermatozoa was scored at 3, 24, 48, and 72 hours after dilution of the neat semen. By completion of 72 hours the efficiency of various treatments over control was in order of 1 and 2% lecithin, 5% glycerol/3% lecithin, 7% glycerol, 1% sorbitol and 0.5% mannitol. Mannitol and sorbitol improved the sperm motility at initial preservation phase, while glycerol at this phase depressed the motility. Lecithin at 1 and 2% levels revealed encouraging results for all the periods. Semen samples diluted in EYC with 5 and 7% glycerol were frozen up to -196 degrees C. Glycerol at 7% level yielded better post thawed revival. There appeared to be bull variation with respect to ultra-low temperature preservation.