Farstad W, Hyttel P, Grøndahl C, Krogenaes A, Mondain-Monval M, Hafne A L
Department of Reproduction and Forensic Medicine, Norwegian College of Veterinary Medicine, Oslo.
J Reprod Fertil Suppl. 1993;47:219-26.
Six unmated blue fox vixens were killed 2-3 days after peak vaginal electrical resistance. Measurements of luteinizing hormone (LH) showed that this corresponded to a time period of 6-10 days after the preovulatory LH peak in these vixens. A total of 63 ova were collected from the oviducts of the vixens, and 45 of the ova were used for study of fertilization in vitro. The ova were placed in 50 microliter droplets of fertilization medium and inseminated with 15,000-45,000 frozen-thawed silver fox spermatozoa that had been separated by swim-up technique, except for nine ova that served as controls for parthenogenesis. Only two of the 36 inseminated ova, both from a vixen killed 6 days after the preovulatory LH peak and inseminated with 15,000 spermatozoa, developed past the four-cell stage. One reached the morula stage 144 h after insemination. Despite a low success rate, the present experiment shows that fox ova matured in vivo may be fertilized and undergo initial embryonic development in vitro.
6只未交配的蓝狐母狐在阴道电阻峰值出现后的2至3天被处死。促黄体生成素（LH）的测量结果表明，这相当于这些母狐排卵前LH峰值出现后的6至10天时间段。总共从母狐的输卵管中收集到63枚卵子，其中45枚卵子用于体外受精研究。将卵子置于50微升的受精培养基液滴中，并用通过上浮技术分离出的15000至45000个经冷冻解冻的银狐精子进行授精，有9枚卵子作为孤雌生殖的对照。在36枚授精的卵子中，只有2枚发育到了四细胞期之后，这2枚卵子都来自一只在排卵前LH峰值出现6天后被处死的母狐，并且用15000个精子进行了授精。其中一枚在授精144小时后发育到了桑葚胚阶段。尽管成功率较低，但本实验表明，在体内成熟的狐卵可能在体外受精并经历早期胚胎发育。
