Effects of Used Engine Oil on the Growth of African Cat Fish (Claria gariepinus)

This research effort evaluated the effects of used engine oil on the growth of African catfish (Clarias gariepinus) juveniles. A total of fifty C. gariepinus juveniles of mean weight 83±0.89g were stocked in 5 plastic containers. These containers were exposed to different concentrations of used engine oil (control (0.00mL/L), 2, 4, 8 and 16mL/L)) for 30 days. Weekly growth performance indices and water quality parameters (temperature, dissolved oxygen, pH) were measured using standard procedures. From the result obtained, it was observed that the tank containing the highest concentration of used engine oil (16mg/L) had the highest mortality of the juveniles and the lowest mean weight gain. It is therefore established that the higher the concentration of used engine oil in the water body the more damage caused to fishes by impeding their growth and causing death especially over long time exposure. This is due to the presence of Polychlorinated Aromatic Hydrocarbon (PAH) and heavy metals contained in it. Therefore, it is recommended that industrial wastes be treated before disposal into the aquatic ecosystems in order to sustain the aquatic species for the future. The enforcement of laws and legislations guiding disposal for the protection of aquatic environment should be enhanced and taken into consideration.