Author : Manjula Saini [ Volume No.:VI, Issue No.IV-July 2017] [Page No : 727-729] [2017]

Matured and acclimatized specimens of Clarius batrachus were exposed to 30 ppm of cupric chloride the fishes were sacrificed on 15th day gonads and thyroid were excised out. Histological preparations by the method of OFG staining were studied. Histological picture of large ova were observed with cracked and broken yolk due to the treatment with various reagent during paraffin impregnation. The young ova proliferated from stroma appear quite small and without distinction of core. Testicular wall were swollen and intermittently disorganized due to over contraction of testicular substance there was irregular hyperplasia of seminiferous tubule due to rise in concentration of protein. Most thyroid follicle have colloidal mass which is dual in nature some of them were partially neutrophilic some follicles have clear and transparent, dark stained colloid with low epithelium. Some follicle appeared like a glass piece and some have distinct epithelium with smooth colloid where as some have stripes of light and dark bands of colloid.