Surface patterns in the reproductive tracts of the rabbit observed by scanning electron microscopy

The ultrastructure of cell surface and tissue organization of reproductive tracts of female rabbits were observed by scanning electron microscopy. In the vagina, straight and shallow longitudinal folds were observed. Complex, very deep, narrow folds with small crypts were observed in the cervix uteri. Two types of cells were recognized: ciliated cells and secretory non‐ciliated cells. The internal os area contained more ciliated cells than the external os area. In the uterus, two different patterns of fold formations were observed: shallow fold formation in a random direction or mosaic pattern in the lower part of the uterus, and wave‐like folds in the middle or upper part of the uterus. The lower part of the uterus contained more ciliated cells than the mid and upper part of the uterus. At the uterotubal junction, four large folds and four small folds from the isthmus are projected into the uterine lumen forming a rosette‐like structure. In the oviduct, longitudinal fold formations were observed through the isthmus to ampullae. The number of ciliated cells gradually increased from the isthmus to the ampullae. The fimbriae, made of several mucosal folds arranged like flower petals, were composed of a high percentage of ciliated cells.