Hepatosomatic index and haematological profile: A bio monitoring tools for assessing african catfish juveniles (Clarias gariepinus) exposed to dimethoate 40% EC toxicity

Abstract

Organosomatic and Haematological Indices are commonly reported in fisheries studies because they are easily determined and can be excellent predictors of adverse health in fish. The objective of the present study was to evaluate the toxicity effect of an organophosphate (dimethoate 40% EC) on catfish (Clarias gariepinus) juvenile using majorly two indices Hepatosomatic Index (HSI) and Haematological parameters. The fishes were exposed to three sub lethal concentrations 0.01 mg/l, 0.15 mg/l and 0.29 mg/l and monitored for 28 days. Result showed a significant decrease in the Hepatosomatic Index (HSI) of the treated groups when compared with the control recording 2.36g, 2.49g and 2.47g for 0.29mg/l, 0.15mg/l and 0.01mg/l respectively. Catfish (Clarias gariepinus) exhibited alteration which was significant (P<0.05) in the total white blood cell count amongst other checked parameters such as Red Blood Cell Count, Packed Cell Volume and Haemoglobin. Result of the study indicates potential toxicity of Dimethoate to juveniles of Clarias gariepinus for which aquatic environment must be continuously monitored.