Studies On The IVF Of Follicular Oocytes In Bovine

In this paper,cattle ovaries collected from Zhengzhou slaughterhouse were used, ability of bovine 2~6mm follicular oocyte for in vitro maturation(IVM),in vitro fertilization (IVF),in vitro culture(IVC)of fertilized eggs were studied, and factors affecting IVMJVF and IVC were also investigated. The results were as follows:1 Single addition of 10%ECS(v/v)in maturation medium obtained high maturation rate (81.39%),cleavage rate (56.05%)and development rate of morula or blastocyst (30.94%).The results indicated futher that single addition of 10% ECS is practicable ,and is fit for applying spreadly.2 GSH(0.5 v g/ml)was added in the medium during in vitro maturation and in vitro culture .The results show that GSH can improve the development rate of morula or blastocyst (32.84%),and rate of blastocyst (26.35%).The results indicated that GSH have promted and protective action in IVD of bovine embryo.3 Addition of 1 f g/ml EOF in maturation medium obtained higher maturation rate(82.50%),cleavage rate (61.43%).The results showed that addition of EOF can promote signigicantly the maturation and cleavage of bovine follicular oocytes.4, Comparative experiments were carried out among swimming -up method, percoll method and washing method of treatment method of frozem-semen in order to observe respective effect of these 3 methods on the in vitro development ability of fertilized eggs.The results show that there was significant differdnce of cleavage rate (p<0.05)between treatment percoll method and washing method;there was significant difference of in vitro development rate of morula or blastocyst (p<0.05) between treatment of swimming -up method and of washing method; but there was not any significant difference of cleavage rate and development of morula or blastocyst between treatment of swimming -up method and percoll method (p>0.05).The results indicated that percoll method and swimming-up method are suitable for applying in IVP of bovine embryos.5 Compared with addition of Gin or addition of Gin and EGF coordinately in embryonoic culture medium,there was significant difference of the development rate of 4-8 cell between control group and addition of Gin and EGF (P<0.05 ) .The results indicated that Gin and EGF can improve the development of 4-8 cell and morula or blastocyst.6 Comparatively feasible and effective IVM-IVF-IVC procedure of bovine follicular oocytes was established as follows: Bovine cumulus-enclosed oocytes were matured in medium-199(with Earle's salts)supplemented with 10%ECS(v/v) and 1 u g/ml EGF.After 23-24h of IVM ,matured oocytes and sperms which come from frozen-semen treated by percoll method (30%-45%percoll )where put in IVF medium contained 3mg/ml BSA, 10 g/ml heparin and 5mM caffeine. Oocytes and sperms were incubated all together for 6~8h,then presumed zygotes were transfered to IVC medium (supplemented with 10%ECS, 1 g/ml EGF and O.lmg/mlGln) bovine GCM to culture, till that zygotes developed to morula or blastocyst.