oxidaseIn untreated (control) cercaria cytochrome oxidase activityranged from 14.51 to 14.91/min/mg protein (Table 4). Significant(p < 0.05) decrease in cytochrome oxidase activity was noted in thewhole cercaria larva of F. gigantica exposed to 60% of 4 h LC50for4 h. Maximum reduction up to 3.71% of control in cytochrome oxi-dase activity was noted in the cercaria exposed to 60% of 4 h LC50of allicin in month of July (Table 4). Significant (p < 0.05) rank cor-relation was noted in between the cytochrome oxidase activity ofcercaria larva and corresponding treatment concentrations of citral,umbelliferone, ferulic acid, azadirachtin and allicin