Participation of the Ovarian Follicle in Control of Time of Oviposition in the Domestic Fowl

Removal of the largest follicle or the yolk of this follicle 2 to 8 hours after ovulation of the oviducal egg invariably led to a delayed oviposition of a few hours while a similar delay was observed in two-thirds of the hens following removal of the second largest follicle. About seventy percent of the hens subjected to removal of the ovarian remnants of the most recently ruptured follicle, or of these remnants together with the largest follicle, held their eggs over 7 hours beyond the expected time of lay. The intraperitoneal administration of a homogenate made from ovarian remnants of ruptured follicles, or the intravenous administration of an extract made from these remnants caused premature ovipositions. It is suggested, therefore, that the ovarian remnants of the most recently ruptured follicle pay an important role in controlling oviposition, presumably through secretion of an aqueous hormone or hormone-like substance.