Massive spontaneous superovulation in a sexually mature pig

Ovulation of 97 follicles was recorded in a gilt that had not received any hormonal treatment, and circumstantial evidence adduced for a rapidly proliferating tumour of the adenohypophysis. A lesser degree of superovulation had occurred in the previous oestrous cycle, whilst the rate of follicular development in the current cycle was exceptional. None of the 93 eggs recovered from the oviducts was a primary oocyte, but three were polyspermic pronucleate eggs. The most advanced stage of embryonic development was that of 4-cells. Such a degree of spontaneous superovulation has never been observed before during careful examination of more than 1200 pairs of ovaries from gilts in the same herd.