Stimulation of the Avian Oviduct by an Ovarian Fragment

NORMALLY the hen will surround with egg albumen and enclose within shell any object of a sufficient size (mature ovum) which passes down the oviduct. In the normal physiological process of egg production the mature ovarian follicle ruptures along the stigma; the released ovum is then engulfed by the infundibulum and as it passes down the oviduct acquires the various layers of egg albumen, shell membranes, and shell. Through some fault in ovulation, weakness in ovarian structure, or excessive physical tension, an intrafollicular ovum may be released or torn intact from the ovary and when picked up by the infundibulum, provides the necessary stimulus for physiological activity of the oviduct. The production of double-yolked eggs containing, in addition to the normal ovum, an intrafollicular ovum with stalk protruding through the shell at the larger end of the egg have been reported by Laboulbene (1859) and Hutt (1946), who also cited . . .