Acute toxicity and effects of sub-lethal malathion exposure on biochemical and haematological parameters of Oreochromis niloticus

The specimens of Oreochromis niloticus were exposed to Malathion to determine the lethal concentration (LC50) value and effects of sub-lethal concentrations on haematological and biochemical parameters. The LC50 value was registered as 1.06 mg/l. Fishes exposed to sub-lethal concentrations (0.12, 0.23 and 0.46 mg/l) for 6 weeks revealed that the pesticide causes alterations in various blood parameters. Red blood cell (RBC) and white blood cell (WBC) counts, haemoglobin concentration and haematocrit values were decreased. Plasma glucose and cholesterol level was elevated whereas plasma protein was decreased in exposed fish. Alanine amino-trasferase (ALT) activity was increased in the fish exposed to Malathion.