SUMMARY:The present paper describes the ultrastructural characteristics of the bulbo-urethral gland (Cowper' glands) of the Indian fruit bat, R. leschenaulti during sexually inactive-breeding cycle. Cyclic histological changes during the seasonal breeding quiescence cycle are not well marked. There are no marked differences. The ultrastructural characteristic of the secretory epithelial cells of BulboUretrhal Gland gland have been studied during different phases of reproductive cycle. The secretory epithelial cells are characterized by the well-developed rough endoplasmic reticulum, extensive developed complexus golgiensis (Golgi apparatus) and mitochondria. Mitochondria with lamellate cristae are dispersed in the cytoplasm. Three different types of secretory granules can be identified on the basis of electron density. These granules are not of different types but they represent the different stages of granule maturation. The secretory products of bulbo-urethral gland of bat are released into lumen both by apocrine and merocrine modes. The functional significance of the secretions of the bulbo-urethral glands in reproduction is discussed.

The present paper describes the ultrastructural characteristics of the Cowper’ glands of the Indian fruit bat, Rousettus leschenaulti during its sexually inactive-breeding cycle. The functional significance of the secretions of the Cowper's gland in reproduction is discussed. In Rousettus, Cowper's glands are small, pear-shaped, bilaterally symmetrical and are situated on either side of the base of the penis. Each lobule is made up of secretory acini lined by columnar or pyramidal cells. Ultrastructurally, the secretory epithelial cells are characterized by well-developed rough endoplasmic reticulum, extensively developed Golgi complex, and mitochondria. Three different types of secretory granules can be identified on the basis of electron density. These granules represent the different stages of granule maturation. The secretory products are released into the lumen both by apocrine and merocrine modes. The secretory material synthesized by the Cowper’ gland may be involved in various male reproductive processes of this species of bat.