impact of cypermethrin on enzyme activities in the freshwater fish cirrhinus mrigala (hamilton)

freshwater fish cirrhinus mrigala were exposed to lethal concentration (5 mg/l) for 1,2,3,4 days and sublethal concentration (1 mg/l) for 1,7,14,21 days of cypermethrin to examine the enzymes activity, in functionally three different tissues namely, gill, liver and muscle. activities of aspartate aminotransferase (aat), alanine aminotransferase (alat) and glutamate dehydrogenase (gdh) increased in all the tissues with increase in exposure time. but in sublethal concentration at 14 and 21 day, a decreasing trend was observed in all the tissues exposed to cypermethrin. at most instances, fish in lethal medium were affected more compared to sublethal concentration.