Identification of the Sex of Earlier Embryos from Generic Hybrids of Chicken-Quail by Wpkci

In this study, a protocol was developed to identify the sex of earlier embryos of chicken (♂)-quail (♀) hybrids and successfully tested the sex proportion of each period (66–120 h). We acquired cross bred eggs by artificial insemination, hatched them in the same batch according to the standard hatching condition of chicken, and collected earlier living embryos at 66, 72, 78, 84, 90, 96, 102, 108, 114, and 120 h randomly. We adopted RT-PCR protocol and multiple PCR, made the known sex quail as the external control, employed β-actin as the internal control, and used primers that were designed according to conservative area of gene Wpkci of quail to identify the sex of earlier hybrid embryos. The results indicated that the primer of Wpkci can be used to identify the sex of hybrid embryos accurately; there were more male than female in earlier embryos, the sex proportion of earlier embryos compared with academic numerical value was significantly different (P <0.01), and there was no difference between different periods (P >0.05). In the present study, we concluded that a simple, fast, credible and stable protocol to identify the sex of earlier hybrids embryos had been established by using primer of Wpkci; in earlier embryos, the death rate of female was higher than that of male and there was no fluctuant peak.