Effects Of Different Preservation Methods On Dolan Sheep Semen Quality And Conception Rate

To maximize the genetic potential of good ram and improve the reproductive performance of ewes, this experiment were to Dolan semen preservation methods and the effect of ram semen with different preservation for artificial insemination were analyzed in order to provide a theoretical basis and technical reference for the sheep industry.In this study, through the application of glucose- lactose- sodium citrate- yolk diluent Ⅰ, glucose, sucrose, citric acid sodium- yolk diluent Ⅱ lactose and glucose--Tris-yolk diluent Ⅲthe effects of three semen preservation methods(room temperature, freezing temperatures and thin tube method) on semen of Xinjiang varieties Dolan sheep were analyzed. The results showed that the semen storage effect at low temperature was significantly higher than that at room temperature and that of frozen. The Sperm Cryopreservation time and survival rate(144h, 0.30) with diluter Ⅱwere significantly different that with diluterⅠ(72 h,0.30) and that with diluter Ⅲ(48 h, 0.35).The sperm motility(0.52±0.07) of frozen sheep semen after thawing with diluter Ⅱ was signif icantly higher than that with diluterⅠ(0.35±0.07), diluter Ⅲ(0.23±0.07)(P<0.05).In summary, diluter Ⅱ was applied to the semen preservation in liquid or frozen.With three different preservation(room temperature, low temperature and cryopreservation),the sperm capacitation, relatively intact and acrosome membrane integrity rate of Dolan sheep semen were analyzed respectively. The results show that:1) frozen-thawed sperm capacitation numbers increased significantly than that treated in normal temperature and low temperature(P<0.05).After thawing process, the number of B-type sperm that indicated capacitation was signif icant increase(P<0.05).2) Frozen The sperm plasma membrane was destroyed in semen frozing, resulting in there are a difference on membrane integrity or acrosomal integrity between the thawed sperm and sperm preserved at room temperature or that at low temperature, indicating that the sperm membrane structure was serious damaged in the process of freezing. The artificial insemination effects with semen preserved in three methods mentioned above were compared. The results showed that there is no difference between the semen preserved at or for 24 h or 72 h and the fresh semen on the ewe conception rate by the insemination.However,the ewe conception rate by insemination with the semen preserved at room temperature for 24 h or low temperature 72 h is high significantly than the frozen-thawing semen.