[Morphological changes in the follicular epithelium in oogenesis of the Peking duck (Anas boschas domestica) and other poultry].

The morphology of the follicular epithelium during the course of oogenesis in poultry (duck goose, hen, turkey) and at the first stages of oocyte growth in some wild birds (finch, totmit, wood-pecker, pigeon) was studied. The general patterns of the follicular epithelium changings are similar in the both groups of birds. In the process of the oocyte growth the flat follicular epithelial monolayer changes to cubic, prismatic, pseudostratified epithelium. It leads sometimes to the impression of multi-layerness owing to its irregular structure. During the oocyte rapid growth the surface of the oocyte increases causing tension on the epithelium layer. This process again turns the pseudostratified epithelium into primatic, cubic and flat epithelium. Pseudostratified structure of the follilicular epithelium is regarded as adaptation to the necessity of the rapid tension during rapid oocyte growth. Correlations of the follicular epithelium morphology with the oocyte diameter are established. Existance of a temporary multilayer stage is discussed with arguments against the interpretation of this stage as a real multilayer.