Improvement Of Follicular Oocytes Maturation In Vitro And Electro Fusion Parameters Of Somatic Cell Nuclear Transplantation In Bovine

Effect of addition of epithelial growth factor (EGF) and insulin like growth factor-I (IGF-I) in culture media on the in vitro maturation of bovine oocytes nuclear and cytoplasm was studied, and the developmental capacities were examined by parthenogenetic activation. In order to improving somatic nuclear transfer reprogramming, the experimentation was conducted to research different parameters of electrofusion, including different electric field intensity, different electric pulse time, donor cell treated with different treated methods(thawing and freshing), different fusion solution and containing cytochalasin B or not in fusion solution . The results as followed:1.The maturation rates of bovine oocytes were examined after cultured for 24 h when EGF concentration in maturation media were 0, 10, 50, 100 ng/mL respectively. Then the oocytes were activated for 5 min in the CR1aa media including 5μmol/L Ionomycin, and cultured for 4 h in the media including 6-DMAP, finally washed in CR1aa media for 3 times and the rates of blastocyst development are examined after cultured 7-8 days. The results showed that the percentage of maturation, cleavage and blastocysts development were 78.28%,86.50%,24.81% respectively when adding 50 ng/mL EGF in media ,which indicated EGF could improve the maturation of bovine oocytes and enhance the developmental rates of bovine parthenogenetic embryos(P<0.05).2.The maturation rates of oocytes were examined after cultured for 24 h when IGF-I concentration in maturation media were 0, 10, 50, 100 ng/mL respectively. The results showed that 100 ng/mL IGF-I could improve the maturation of bovine oocytes and enhance the development rates of bovine parthenogenetic eggs development(P<0.05).3.The maturation rates of bovine oocytes were examined after cultured for 24 h when adding 50 ng/mL EGF and 100 ng/mL IGF-Ⅰin maturation media. The results showed that EGF/IGF-I could improve the maturation of bovine oocytes and enhance the development rates of bovine parthenogenetic embryos developmental capacity (P<0.05). EGF/IGF-I could improve nuclear maturation and cytoplasmic maturation of bovine oocytes.4.During the special electric fusion manipulation(20μs,2 times pulse,10 ms), the...