Study On Three Sugars And Antioxidants For Crypreservation Of Boar Spermatozoa

The cryopreservation of boar semen in still diffcult for large-scale use due to the low sperm viability following thaw and low fecundity rates after artificial inseminations.in order to improve the quality of frozen-thawed boar semen and protect spermatozoa against cold shock.In this study, rhodiola polysaccharide,lycium barbarum polysaccharide and trehalose as cryoprotectors, cysteine,lutathione and hypotaurine as antioxidants added in the diluents1 In order to improve the sperm quality of frozen thawed boar semen, rhodiola polysaccharide,lycium barbarum polysaccharide and trehalose were added into the basic extenders----Tris-Citric-Glucose(TCG). Moreover,in order to determine the optimum concentration of rhodiola polysaccharide,lycium barbarum polysaccharide and trehalose,we used four different concentrations : 2%,4%,6%,8%(w/v), respectively.Extenders supplemented with 6% rhodiola polysaccharide,2～4% lycium barbarum polysaccharide and 4% trehalose on cryoprotection of spermatozoa were better that of traditional TCG without supplement.Sperm motility, viability, mitochondrial activity, menmbrane integrity and acrosome intregrity were improved,as compared to TCG(P<0.05).The effect of cryoprotection: rhodiola polysaccharide>trehalose>lycium barbarum polysaccharide.2 The motility of frozen-thawed sperm were significantly different among three methods of thawing(P<0.05), the best motility of frozen-thawed sperm was obtained using 50℃,12s. In groups incubating at 37℃, the best effect was obtained when incubating 45s.3 the frozen-thawed sperm motility using 0.25ml straw was no significant different from that using 0.5ml straw (P>0.05).but the motility using 0.25ml straws(37.97%) is higher than that using 0.5ml straw(37.20%).4 The highest rates of viability, menmbrane integrity and acrosome intregrity of frozen- thawed sperm were obtained in group adding 5 mM cysteine. And it was not significantly different in group adding 2.5 mM cysteine (P>0.05). But the rates of viability, menmbrane integrity and acrosome intregrity of frozen-thawed sperm in goups adding 5mM and 2.5mM are significantly higher than those in other groups.5 The viability, menmbrane integrity and acrosome intregrity of frozen-thawed sperm was improveed distinctly in group adding 1 mM glutathione. The prime concentration of glutathione was 1mM.6 The rates of menmbrane integrity and acrosome intregrity in 1mM hypotaurine group were significantly different from those in other groups. But the rates of viability in groups adding hypotaurine were not significantly different from that control group.7 The damage of sperm DNA could be caused by frozen-thawed. It lowers the rate of damage when adding 2-3% glycerol.8 The damage rates of frozen-thawed sperm DNA were lowered significantly when adding 2.5～5mM cysteine, 1mM glutathione and 1mM hypotaurine(P<0.05).