water pollution, pesticides, fish


The water pollution of aquatic environment with wide array of pesticides has become a menace to the aquatic flora and fauna. The organophosphorus pesticide malathion has been widely used in agriculture for several crops such as paddy, cotton and vegetables to control serious insects and mites. These chemicals cause severe damage to aquatic ecosystem especially to fishes. The main aim and objective of present study is to evaluate the impact on protein and glycogen in fingerlings of Labeo rohita an economically important Indian major carp. The 96 hrs LC50 value of malathion for L.rohita was 9.0 ml/L. No mortality was observed below the concentration of 7.5 ml/L. The changes in biochemical parameters such as protein and glycogen are important to indicate the susceptibility of organs system to pollutants by altering their function. In the present investigation the protein and glycogen contents of muscles, gills, liver, kidney and brain of L.rohita were analysed. Fish reared in control group registered high protein and glycogen contents when compared with malathion treated groups during 24, 48, 72 and 96 hrs respectively. The similar results were obtained in the oxygen consumption of L.rohita during 24, 48, 72 and 96 hrs respectively It is concluded that malathion concentrations (low and high) is very toxic and causes alterations in vital organs of fish L. rohita.