Abstract: The method of RT-PCR was used to multiply PCR to identify and clarify the quail embryo sex form 66 to 120 hatch hours with primers of Wpkci and β-actin，then selected four embryos of female and male respectively at each period，taken β-actin for internal standard to determine the relative quantity of embryo bcl-2 mRNA，to investigate the influences of apoptotic factors bcl-2 on early embryos of quail.The results showed that:
① The bcl-2 mRNA expression of male embryos maintained lower level between 66 to 90 h of embryo stage，and it rose slowly between 96 to 102 h，the differences were not significant (P＞0.05);The bcl-2 mRNA expression of male embryos declined on 108 h(P＜0.05), but it rose distinctly on 114 h compare with 108 h (P＜0.05),then maintained higher level on 120 h.The bcl-2 mRNA expression of male embryos were higher than female embryos from 66 to 108 h (expect 72 h),but they were lower than female embryos from 114 to 120 h of embryo stage. ② The bcl-2 mRNA expression of female embryos maintained lower level between 66 to 90 h of embryo stage; it rose distinctly on 96 h compare with 90 h(P＜0.05),and declined slowly from 96 to 108 h ,the differences were no significant of them (P＞0.05), then declined distinctly between 114 to 120 h compare with 108 h (P＜0.05). ③ On the stage of 84 h, the bcl-2 mRNA expression of female embryos were higher than male embryos, and the difference was significant (P＜0.05); The expression of bcl-2 mRNA in female embryos were higher than male embryos at 90 and 108 h of embryo stage (P＜0.01). But, the bcl-2 mRNA expression of male embryos were very higher than female embryos at 120 h of embryo stage (P＜0.01).To some extent，bcl-2 mRNA expression of female and male embryos in the embryonic development was sequential,indicated that the bcl-2 genes had an important effect on the development of the quail embryos.

Key words: quail; early embryo; bcl-2; RT-PCR