Histochemical research into the facial caruncle of the Muscovy duck (Cairina moschata domestica L.) and its relationship with the adrenal glands and gonads.

Histochemical studies carried out on prepuberal and adult, males and females, Muscovy ducks (the Black ancestral variety) showed that the beginning of the facial caruncle is caused mainly by local androgenic activities. In adult males, support for this organ comes from the steroid hormones originating from the adrenal gland and testis. In adult females, caruncular androgenic activity also seems to be necessary for the support of this organ.