Induced ovulation, development of the corpus luteum, and tubal transport in the striped skunk (Mephitis mephitis).

Ovulatory pattern, development of the corpus luteum (CL), and early tubal transport are described for 6 unmated and 19 mated striped skunks (mephitis mephitis) killed after known copulation times. Ovulation is induced by copulation and occurs around 42 hours (range = 40--50 hours) after first insemination. Seventeen of 19 females killed between 36 hours and 19 days postcoitus had ovulated. Two females killed at 36 hours had not ovulated; however, their follicles showed preovulatory changes and were significantly larger (p less than 0.01) than those of unmated females. Six unmated females, killed during and three weeks after the normal breeding season, had not ovulated. Ovarian events, such as preovulatory changes, ovulation, and development of the corpus luteum (CL), are described for animals killed 36 hours to 19 days post-coitus. Maximum CL size occurred at 11 days post-coitus and coincided with the onset of embryonic migration and enlargement. Embryonic development reflected individual variation in ovulation times. The first polar body was extruded at ovulation and the second at fertilization. Pronuclear stages were predominant at 42 to 48 hours and 3 to 8-cell stages at 72 to 96 hours; morulae (containing up to 95 cells) entered the uterus at seven days. Blastocysts were observed first at 11 days when embryonic spacing and enlargement began. Implantation occurred by 19 days.