Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Effects of Protein Source and Energy Substrates on the In Vitro Development of Bovine Embryos in a Two-step Culture System | J. Vet. Sci. 2003 4 1 73-78 JOURNAL OF Veterinary Science Effects of Protein Source and Energy Substrates on the In Vitro Development of Bovine Embryos in a Two-step Culture System Kwang-taek Lim Byeong-chun Lee Sung-keun Kang and Woo-suk Hwang Department of Theriogenology Biotechnology College of Veterinary Medicine Seoul National University Seoul 151-742 Korea Received December 16 2002 Accepted March 3 2003 Abstract In this study we examined the effects of a two-step culture system which involves the use of different culture media for early cleavage and later stage embryos on the in vitro development of bovine em bryos. We also investigated the effect of glucose phosphate and citrate on the in vitro early developmental period of bovine embryos in a two-step culture system. Moreover the supplem entation of different protein sources BSA-V BSA-FAF and FBS during IVC did not affect the frequency of blastocyst development. Using two-step culture embryos were cultured in protein-free media for an initial 5 days. This was then follow ed by the same culture media or an FBS supplem ented media. The developmental rates of blastocysts in the FBS containing group were significantly higher than in the replaced with no se rum containing group. Em bryos cultured in mSOF supplemented with mM glucose plus mM phosphate w ere significantly inhibited. The inhibition of developm ental com petence by glucose plus phosphate was consistent with the existence of mM sodium citrate. This study indicates that a two-step culture system which applies different conditions for early cleavage em bryos . serum-free m edia vs. later stage embryos with serum containing m edia m ay be effective for in vitro production system s. In addition the developm ental competence of bovine em bryos was depressed in the presence of glucose plus phosphate as compared to either alone or the a b s e n c e o f b o t h . Th e r e fo re t h e a v o i d a n c e o f t h i s negative effect should allow m
