卵黄和低密度脂蛋白对冷冻保存绵羊精子胆固醇、磷脂含量的影响

Effects of Egg Yolk and LDL on Changes of Cholesterol and Phospholipids in Sheep Spermatozoa during Freezing

为了探索绵羊冷冻精液受精率低的原因,在稀释液中用低密度脂蛋白代替卵黄冷冻绵羊精液,研究LDL对冷冻中精子脂类含量的影响。结果表明,以卵黄稀释液冷冻精液,精子胆固醇含量从鲜精的234.54 nmol/109降低到163.76 nmol/109精子,胆固醇与磷脂的比值(c/p)从0.54下降到0.36;以9 g/100mL LDL代替卵黄,冷冻后胆固醇含量为243.73 nmol/109精子,c/p值保持在0.50。研究得出在卵黄稀释液中冷冻绵羊精液,精子胆固醇流失,c/p值下降;以LDL代替卵黄,可有效保护精子胆固醇,避免流失,维持了精子c/p值。

For search the reasons of low pregnant rate of sheep frozen semen, the paper studied on the changes of cholesterol and phospholipids in sheep spermatozoa during freezing, which was protected with egg yolk or low density lipoprotein（LDL）in diluents. The results indicated that the contents of cholesterol of sheep spermatozoa decreased from 234.54 nmol/10^9 sperm of fresh semen to 163.76 nmol/10^9 sperm of frozen semen and the ratio of cholesterol and phospholipids （c/p） decreased also from 0.54 to 0.36 when egg yolk was added in diluents. When egg yolk in diluents was instead with LDL 9 g/100mL, content of cholesterol in spermatozoa was 243.73 nmol/10^9 sperm after frozen and c/p was also maintained 0.50. In conclusion, the content of cholesterol and c/p in sheep spermatozoa decreased during freezing in egg yolk extender and LDL could prevent the content of cholesterol and c/p from decreases.