Optimization Of Platform For Bovine Somatic Cell Nuclear Transfer

In this study, the systems for in vitro maturation of bovine oocytes and parthenogenetic embryos culture were optimized. The effects of three different maturation mediums (mTCM-199, SOF and 1600 medium) on maturation of bovine oocytes and two commercial embryo mediums on parthenogenetic embryos developemnt were compared. In addition, we also compared the efficiency of the two different donor cells (bovine ear fibroblasts and cloning bovine ear fibroblasts) on bovine somatic nuclear transfer. Use closed bag culture embryo. The results are showed as following:1. The effect of three differential mediums on the oocyte maturation and parthenogenetic embryos development were studied, the results showed the maturation rate(77.99% vs 64.84%, P<0.05) was significantly higher in SOF mediums than that in mTCM-199 mediums, but the cleavage rate (81.11% vs 71.13%, P<0.05) in mTCM-199 mediums was significantly higher than the SOF mediums, and there was no significant difference in the parthenogenetic blastocyst rate (24.64% vs 24.14%, P>0.05) between this two groups. The rate of maturation, cleavage and blastocyst in the 1600 medium group was significantly higher than mTCM-199 and SOF groups.2. The rate of maturation (74.79% vs 71.69%, P>0.05), embryo cleavage (83.07% vs 81.39%, P>0.05) and blastocyst rate (26.75% vs 22.87%, P>0.05) of the closed bag culture methods was not significantly higher than that of no closed bag culture.3. The results demonstrated that there were no significantly differences in the cleavage rate (86.45%vs.82.30%, P>0.05) between the mediums made by Vitrolife Company and SAGE company,and there were significantly differences in the blastocyst development rate (33.45% vs 21.20%, P<0.05).4. The rate of fusion (92.12% vs 87.68%, P<0.05) and blastocyst (32.68% vs 23.19%, P<0.05) development of the cloned embryos derived from cloned cattle ear fibroblast cells is significantly higher than that from ear fibroblasts.The results show:(1) mTCM-199 medium is better for embryo development than SOF medium, but the 1600 culture medium is the best medium for bovine occyte maturation among three mediums;(2) the closed bag culture method is a suitable method for bovine embryo culture and adaptable for in some primary research agencies; (3) the effect of two emrbyo culture mediums on bovine embryo development is significantly different, the medium from Vitrolife is more effective than SAGE. So we select to use the embryo culture medium from Vitrolife; (4) For choosing donor cells, the effect of embryo development derived from in cloning bovine ear fibroblasts as donor cells for somatic nuclear transfer is more efficient than bovine ear fibroblasts.