Prakriti Verma*, G. B. Chand & A Nath
Department of Zoology, Patna University
Received 11th June,2008 ; Revised 23rd August,2008
Abstract : Air breathing fish Clarias batrachus were exposed to rogor 2 m1L-1 a dimethoate pesticide for a period of 21 days. Tissues of liver were dissected from normal and rogor toxicated fish after 1st, 2nd and 3rd week of exposure period. Light and Electron microscopic studies were done. In rogor treated fish, hepatic cellular abnormalities were observed, viz. disruption of hepatic lobular boundary membrane, necrosis, breakage of bile canaliculi, central canal and pycnotic nuclei under the light micrographs increases with every doses and duration. Under Transmission Electron Microscopy after 1st week of rogor exposure increased sinusoidal spaces, increased stacks of Rough Endoplasmic Reticulum which studded with ribosome and electron dense granules was found. Nucleus pseudopodial shaped showing granular nucleoplasm with more heterochromatin than euchromatin material and diffused nucleolus. After 2nd week rogor exposure increased vacuolations and decreased matrix of hepatoplasm have been seen. Nucleus with disrupted nuclear membrane and dilated nuclear pore are significant abnormalities. Increased stacks of endoplasmic reticulum, polyribosome, glycogen rosette and severe autolysis of cell organelles have been very well seen under the Transmission Electron Microscopy in the 3rd week of rogor exposure. Increased heterochromatin, granular central chromatin and enlarged nucleolus confirm the hyperactivity of cell. Such types of abnormalities have never been found in the normal hepatic cells.