Seller M J, Perkins-Cole K J
J Reprod Fertil. 1987 Jan;79(1):159-61. doi: 10.1530/jrf.0.0790159.
Sixty-seven mouse embryos from 10 litters collected on the morning of Day 9 of gestation, when neurulation is beginning, were classified according to the precise stage of development reached, and sex-chromatin analysis was performed on the yolk sac. Within litters, the least developed embryos were more likely to be female than male, while the most advanced embryos were predominantly male. Taking all embryos, the mean somite number was greater in males than females.
在妊娠第9天上午收集的来自10窝的67个小鼠胚胎（此时神经胚形成开始），根据发育达到的精确阶段进行分类，并对卵黄囊进行性染色质分析。在同窝胚胎中，发育最不完善的胚胎雌性比雄性更常见，而发育最成熟的胚胎主要是雄性。就所有胚胎而言，雄性的平均体节数多于雌性。
