Vol. 3, Special Issue 3, Part B (2017)

Abstract
Pollution of water is responsible for a very large number of mortalities and incapacitation in the world. Polluted state of water resources has led to a steady decline of fish population. Pollution to biosphere by insecticide is characterized by presence of water residues in food products, the persistence in natural conditions and their circulation along food chain. The insecticides which are liberated into aquatic ecosystem have a tremendous effect on fish and thereby to man. The present study has been undertaken to investigate the effect of cypermethrin on freshwater edible fishes Channa orientalis, Clarias batrachus and Heteropneustes fossilis, which reveals that the immune system of fishes is very badly affected due to fluctuations in leucocytes count of fishes as the exposure period increases reflecting the immune system of fish to withstand stress.