Abstract

In the present study the histopathological effects of gasoline on the gills of Oreochromis niloticus as a sensitive indicator for the pollution were experimentally determined to evaluate the health of the fish. The results indicated that the most prevalent lesions were epithelium lifting, distortion of lamellae, clubbing, fusion of the adjacent secondary lamellae due to hyperplasia of the respiratory epithelium and cells at the base of the secondary lamellae and aneurysm in the gills. The severity of the lesions observed in this study differs with the concentration of toxic material involved in that experiment. This in turn affects greatly on gas exchange, respiration and excretion of metabolic waste products.

Key words: Nile tilapia, Gasoline, Gills, Histopathology