Abstract

The Indian wild caught bat, Taphozous kachhensis at Ambai Nimbai (Maharashtra) shows continuous asynchronous breeding, exhibiting a seasonal polyoestry. The adrenal gland of T. kachhensis is made up of adrenocortical and chromaffin tissues. The adrenocortical tissue is comprised of two main types of cells, the steroid cells with abundance of lipid inclusions and eosinophilic cells with eosinophilic granular cytoplasm. The chromaffin tissue is intermingled with adrenocortical tissue. They are formed of adrenaline and noradrenaline secreting cells with different electron density and variable sizes. The zona glomerulosa during estrus shows spherical nuclei with prominent nucleoli. Adrenal gland of pregnant female shows striking differences in ultrastructural features than those observed in the adrenal gland of non-pregnant female. During pregnancy, the cells of zona glomerulosa are hypertrophied and synthetically very active. The lysosomes and few lipid droplets are seen in cytoplasm of cell. The cells of zona fasciculata are large, vacuolated and arranged in cords of polygonal cells having mitochondria with tubular and lamellar cristae. The lipid droplets are observed in close association with smooth endoplasmic reticulum and mitochondria suggesting the role of these organelles in steroidogenesis. The cells of zona reticularis are loaded with lipid droplets. The mitochondria are spherical in shape with collapsed cristae. The cells of zona reticularis are in close association with blood vessels. Few lysosomal bodies are seen in the cytoplasm. Adrenal medulla consists of two types of cells depending on the presence of secretory granules. Nor-epinephrine cells are predominant in the medulla of pregnant bat while epinephrine cells are predominant in the medulla of estrus bat.

Key words: Bat, adrenal gland, medulla, ultrastructure, reproductive cycle.