Fructose Metabolism Of Goat Semen Liquid-stored In The MES Extender

The best way for semen storage is cryopreservation, which has been used for bull semenstorage and artificial insemination successfully. Cryo-preservation of bull semen has beencommercialized for many years. However, the cryopreservation for goat semen is notsuccessful. Although the motility of post-thaw semen is up to30%, the fertility rate andpregnancy rate are much lower than that of fresh semen. It is necessary to find a long-timeliquid storage protocol and improve the quality of liquid storage at present, and it is criticaltechnology in expand the use of artificial insemination. On The basis of the motility of semencoated with MES in pH6.25is up to in16th day, we employ the semen stored for12、13、14、15、16days for artificial insemination, and record the return rate and conception rate forassessment of storage efficiency.Motility and fertility of stored semen is influenced by so much factors as electrolyte,oxidative stress, metabolic acidosis, DNA fragmentation, Shedding off specific lipidconstituents from sperm cell membrane during preservation, acrosome reaction andspontaneous capacitation etc. It is necessary to find and eliminate these unfavourable factorsand to construct a chemical defined extenders and an efficient semen storage protocol toexpand liquid storage semen in in vitro fertilization and artificial insemination. Therefore, theapplication of chemically defined extenders will have obvious advantages in long term liquidstorage of buck semen. At the same time this system will provide a platform for investigatingmetabolism mechanism of goat sperm during long term liquid storage. The aim of the presentstudy was to construct a chemical defined and simple extenders to investigate fructosemetabolism during liquid storage. The results are summarized as follows:1Semen can maintain motility for4days in15℃,and the metabolism frequency ismoderate.2It is favourable for liquid storage in15℃to supplement fructose to BM, the best resultis obtained with10mM/L fructose. When the concentration over10mM/L, it is unfavourablefor liquid storage. 3Motility of goat sperm extended with BM containing fructose supplied withiodoacetate, inhibitor of glycolysis, were lower significantly than the control which didn’tcontain iodoacetate. Meanwhile the time of sperm motility of exceeding30%maintained fordeclined significantly.4Motility of goat sperm extended in BM containing fructose supplied withdehydroepiandrosterone(DHEA), inhibitor of pentose phosphate pathway, were notsignificantly lower than the control which didn’t contain dehydroepiandrosterone. But theresult still to be certificated.5Liquid storage semen in15th、16thfor artificial insemination can not make ewesconception, ewes return to estrus.6The motility of liquid storage semen in12th、13th、14this up to50%, when used forartificial insemination maybe can get better result. The result have not been obtained.The results show that:1) liquid storage semen in15th、16thfor artificial insemination cannot make ewes conception, ewes return to estrus;2) It is favourable for liquid storage in15℃to supplement fructose to semen extender;3) the best result is obtained with10mM/L fructose,it is unfavourable for liquid storage over10mM/L;4) Sperm metabolizes fructose byglycolysis pathway, because of inhibiting glycolysis pathway influence sperm’s survivalduring long term liquid storage at15℃;7)Sperm maybe metabolizes fructose by pentosephosphate pathway, the result still to be certificated.