Fenvalerate and Cypermethrin used as insecticide or pesticide are toxic agents compared after the application of herbal agent Psidium guajava upon Catfish Clarias batrachus (Linnaeus, 1758). Both toxic agents showed toxicity whereas Psidium guajava gave some recovery effect upon pesticidal infected Catfish. Fishes were exposed to the concentration of pyrethroid insecticide Cypermethrin for 24h as the LC50 value was found to be (1 μg/l) and one fourth of LC50(0.25 μg/l) was selected. The other insecticide Fenvalerate concentration for 24 h was LC50 (250 μg/l) and one tenth of LC50 (25 μg/l) as lethal concentration for acute toxicity studies. Doses followed till 96 h at each time interval of 24 h. The dose of herbal given for 24 h was 9 gm for 1.5 kg body weight of fish. Biochemical changes were observed in all five Normal, Fenvalerate, Cypermethrin, FenPg and CypPg stages.
