HISTOPATHOLOGICAL ALTERATIONS IN THE GILLS OF FRESH WATER FISH, LABEO ROHITA (HAMILTON-BUCHANAN) EXPOSED TO HEAVY METAL MIXTURE (Cd, Cr 8#x38; Pb)

Abstract

Histopathological alterations are the changes arising in the tissues of the organisms after exposure to the certain pollutants. Histopathology has been widely used as biomarkers in the analysis of the health of fish exposed to pollutants. Thus they are recommended as useful biomarkers in eco-toxicological research, risk assessment and monitoring programs. The heavy metals like cadmium (Cd), chromium (Cr) and lead (Pb) are very toxic to animals which enter surface water from various sources. Fishes carry on in near contact with the water through their gills and thus liable to heavy metals exhausted from various sources. In this study, an effort has been made to assess the effect of heavy metal mixture on the gill tissues of Labeo rohita. The fresh water fish, labeo rohita were exposed to heavy metal mixture for short term exposure period (24, 48, 72 8#x38; 96 hours). After the stipulated period of exposure fishes were sacrificed and gills were isolated and used for histopathological studies. The important alterations in the tissues were noticed. Gill tissue found that degeneration of epithelial lining and fusion of primary lamellae.