Sub-Lethal Effect of Monocrotophos on Growth and Food Utilization of the African Cat Fish Clarias gariepinus (Teugels)

The effect of sub-lethal concentrations 2.51, 5.02 and 10.04 mg L 1 of monocrotophos (organophosphorus insecticide) on growth, nutrient and body composition of Clarias gariepinus were studied in the laboratory. The growth rates were significantly reduced in fish exposed to the toxicant compared with the control groups. The nutrient utilization showed that, SGR, FCR, FCE, FE, PER and NM were significantly higher (p< 0.05) in the control fish compared to the exposed groups. Similarly, the percentage crude protein and oil content were significantly higher (p< 0.05) in the control than the exposed groups. The investigation revealed that, low concentration of monocrotophos causes various physiological effects in this fish. The usage of this insecticide near water bodies for fish production should be monitored and control.