Abstract: Objective To compare the fertilization in vitro in various mouse strains and the effects of different culture medium for development of embryos in C57BL/6J mice in vitro. Methods Females from 7 strains of mice were superovulated and operated by IVF, and the average number of superovulation and the fertility rate were observed. HTF、CZB、KSOM、Ml6、 HECM were used as the culture medium to culture the2-cell of C57BL/6J mice in the same condition and the development rate from 4-cell to blastcyst were observed respectively. Results there is a significant difference (P＜0.01) in the average number of superovulation markedly among 13.0—38.7, and the rate of fertility of individual mouse with a range of 70.2% to92.8% (P＜0.05). The development rate of 4-cell, 8-cell, morula and blastcyst in the 5 culture mediums with a range of 60.3%?95.8%、52.8?91.1%、40.6—87.5% and 5.1%?75.4% . Conclusion the genetic background is a primary factor for the effect of superovulation and fertilization in vitro in mice. Glucose can result in 2-cell interdiction of the embryo development; it is not primary energy substance before 8-cell. Phosphate can result in retardarce of the embryo development. Amino and EDTA are beneficial for overcoming the block of the embryo development.

Key words: Mouse, in vitro fertilization, Embryo development