[Ultrastructure of 3 beta HSDH (delta 5-3 beta hydroxysteroid dehydrogenase)-containing cells in ducks. III. Hybrid ducks (Anas platyrhynchos male X Cairina moschata female) during egg laying].

All the cells of the ovary of the hybrid duck (Peking duck X Barbary duck) which contain an active 3 beta HSDH enzyme show ultrastructural characteristics of steroid cells: a smooth, developed reticulum, tubularcrested mitochondria, a considerable "charge" in lipid inclusion. These cells are found not only in the internal theca of follicles as with the female gender, but also in the cortical zones void of germinal elements, a tendancy particular to the female.