EFFECT OF MERCURIC CHLORIDE ON GILL STRUCTURE OF A FRESHWATER FEMALE CRAB, BARYTELPHUSA CUNICULARIS (Westwood)

Fresh water crabs are economically important and an alternative source of significant human dietary constituents. The experimental crabs treat ed with lethal concentrations (1.04, 0.84, 0.63 and 0.45 ppm) of mercuric chloride showed many histological changes during 1 to 4 d of exposure. The gills showed vacuolization in the gil l stem, gill lamellae ruptured, connective tissue cells in the stem damaged, destructed and co ngestion of haemocytes in the gill lamellae are observed. The present work on histological obse rvation was carried out to know lesions in gills that had resulted from lethal exposure of the freshwater female crab, Barytelphusa