Optimization of Culture Measure for Bovine-bovine and Goat-bovine Cloned Embryos in vitro

Abstract:

This study is conducted to explore an effective culture method for supporting the embryo development. The cattle fetal ear fibroblasts and the goat fetal ear fibroblasts are transplanted into the enucleated cattle oocytes separately by oocyte intraplasmic nuclear injection method to construct bovine cloned embryos and goat-bovine cloned embryos. The embryos are first cultivated in modified charles rosenkrans 2 amino acid medium (mCR2aa) and modified synthetic oviduct fluid medium (mSOF) separately. Then BSA(8mg/mL) or FBS(10%) can be added to mSOF according to the different culture period. The supplements and orders, added during the first three days and after three days are as follow: BSA and BSA, BSA and FBS, FBS and BSA, FBS and FBS. On the basis of the cleavage rate, 8/16-cell rate, blastocysts rate and total cell number of blastocysts, the best culture way can be screened out. Result: First, cleavage rate, 8/16-cell rate, blastocysts rate and total cell number of blastocysts, cultivated in mSOF solution are all higher than those cultivated in mCR2aa(P<0.05).Second, the cleavage rate and 8/16-cell rate, adding BSA and FBS into mSOF, are in turn 79.8%±7.1%, 49.7%±3.5%, 21.5%±1.8%, and 115.2±4.3 in bovine cloned embryo, and 40.1%±6.3%、29.2%±2.0%、13.4%±2.1% and 100.1±3.0 in goat-bovine cloned embryo, which are significant higher than other culture groups(P<0.05).Conclusion: The goat-bovine cloned embryo can be cultivated by the optimized culture measure of bovine cloned embryo. The best culture ways of bovine cloned embryo and goat-bovine cloned embryo are all to use mSOF supplemented BSA in the first three days and then use mSOF supplemented FBS in the next five days.

Key words:bovine, goat, Somatic cell nuclear transfer, embryo