Five strains of mouse (CD-I, B6DF1, FVB, C57BL/6 and DBA) oocytes were removed cumulus cells, dissected partial zona-pellucida, surrounded by cumulus cells. The techniques of IVF, culture and embryos transfer were used.

• 对CD-1、B6DF1、FVB、C57BL/6、DBA小鼠的卵母细胞进行直接、去卵丘细胞、切割透明带法处理后，再分别进行体外受精、体外培养和胚胎移植试验。