beta-Glucuronidase activity in the developing uropygial gland

The presence of sterolic compounds and beta-glucuronidase activity have been studied in the uropygial glands of chick embryos (18th day of inc.), chickens (3 weeks after hatching) and young fowls (5 months old). Sterols are histochemically detectable only after hatching and beta-glucuronidase activity, very faint before hatching, reaches its maximum in chicken glands with a peculiar inner localization coincident with sterolic localization. It is suggested that beta-glucuronidase has in uropygial gland a double functional significance: a certain amount of activity is developed to cell proliferation whereas a more strong activity is involved in the hydrolysis of sterol glucuronides.