Histochemical studies of the development of alkaline and acid phosphatase activities in the ovary and oviduct of the fowl (Gallus domesticus).

Alkaline and acid phosphatase activities were studied in the ovary and oviducts of pullets from the age of 2-32 weeks. Adult fowls were similarly studied. Alkaline phosphatase activity was present only in the glandular grooves and crypts of the immature oviducts. Alkaline phosphatase activity appeared at the pits of epithelial evaginations as glandular formation commenced. The young, non-secreting glands also showed the enzyme activity. But in the mature oviduct, alkaline phosphatase activity was confined to only the uterovaginal glands or sperm host glands and the epithelium of the vagina. In the ovary, alkaline phosphatase activity in the theca interna increased as the diameter of the follicles increased. Acid phosphatase activity was not present in the ovary, but in the oviduct, the enzyme activity was present in the uterine (shell gland) glands and in the uterovaginal epithelium and glands (sperm host glands). Alkaline phosphatase activity in the ovarian follicles and in the immature oviduct is thought to be related to histodifferentiation of these structures.