Two types of cells line the oviduct of the adult rabbit: ciliated and secretory. There is great variation in the time of differentiation of the epithelial cells to these mature types. Approximately 7 days after birth, some cells programed to become secretory exhibit the preliminary cytological changes: an increase in the size of the Golgi complex and an increase in the amount of rough endoplasmic reticulum. Initial stages of ciliary development are also seen in some of those cells destined to bear a ciliated border.

By 12-20 days after birth, the size of the Golgi complex and the amount of rough endoplasmic reticulum has markedly increased in the secretory cells. In the isthmus, secretory granules can be observed in the Golgi region and also in the apex of the cell. Mature ciliated cells are present at this time.

Twenty-four to sixty days after birth, secretory cells containing secretory granules are present in both the ampulla and isthmus of the oviduct. The secretory granules of the ampulla are generally more electron-dense than those of the isthmus. By 90 days after birth, the epithelial cells lining the oviduct appear very similar to those of the adult; the secretory cells are packed with secretory granules, and release of these granules into the tubal lumen is observed.