Histological changes, Micronuclei induction and Nuclear abnormalities in the peripheral erythrocytes of Clarias gariepinus (Burchell 1822) exposed to water sample from Apodu Reservoir

Abstract

Pollution of water bodies in most developing countries is of grave concern since toxic pollutants interact with the genetic blueprints of aquatic organisms leading to a variety of illnesses. In this study, histological changes in the gills, liver and kidney as well as the genotoxic effect of water sample from Apodu reservoir, were investigated in the peripheral erythrocytes of cultured catfish (Clarias gariepinus) using micronucleus assay. They were exposed to the water sample for a period of 3, 7 and 14 days. The physico-chemical (pH, temperature, transparency) and heavy metals analysed (Ca>Mg>Fe>Zn>Mn>Cu>Ni=Pb=Cd=Cr) were all within the acceptable limit permissible. However, the micronucleus test shows statistically significant (p<0.05) induction of micronuclei and nuclear abnormalities as compared to the control (borehole water). The histopathological analysis shows some mild alterations in the organs such as distortion and infiltration of lymphocytic cells of the gills. We also reported mild distortion of hepatic tissue of the liver as well as abnormal nephron and glomeruli with congestion and vascular dilation of the kidney. These alterations might be due to anthropogenic activities that pollute the water body. Therefore, the influx of agricultural and domestic waste into the Apodu reservoir should be discouraged as part of remediating efforts.