Seasonal Changes in the Secretory Activity of Seminal Vesicles of the Indian Fruit Bat Rousettus leschenaulti (Desmarest 1820)

The epithelium of the seminal vesicles of Rousettus leschenaultia shows cyclical pattern in the secretory activity during the reproductive cycle. During the sexually quiescent phase, the seminal vesicles are regressed; the cytoplasm of the epithelial cells contains coarse secretory granules and the lumina of the tubules are empty. The secretion is in the form of secretory blebs in this species of bat. The formation of secretory blebs from the columnar epithelial cells is initiated during the recrudescent phase and is at its peak during the active breeding phase. These secretory blebs are discharged into the lumen of the tubules. Lumina of the tubules are filled with secretory blebs during the recrudescent and active breeding phases. Later on these blebs disintegrate and dissolve to form a homogenous material in the lumen of the tubules. Thus, the mode of secretion in the seminal vesicle of Rousettus is apocrine. The functional significance of the secretion of the seminal vesicles in reproduction of male bat is discussed.