Histological changes of electric yellow (Labidochromis caeruleus) exposed to three different copper concentrations

Abstract

The water pollution is affecting rivers, lakes, and seas. Therefore, all aquatic organiss may influenced by it. In this study, it was intended to examine and assess histological changes in the electric yellow cichlid exposed to three different periods of copper concentrations (acute, chronic and not containing copper). Firstly, this study was formed in three parts of acute and chronic exposures and recovery. Electric yellow cichlid were exposed to 0, 10, 20, 30, 40 mg l-1 of copper sulfate for 96-h acute trial. Secondly, they were exposed to 0.0, 0.5, 1.0, 2.0, 4.0 mg l-1 of copper sulfate for 20-d chronic trial. Thirdly, survived fish from the chronic trial were holded in clean water without copper for 10-d recovery. At the end of three trials, gill, liver and spleen samples of fish were collected and stained with hematoxylin-eosin (H&E) techniques. Preparations were examined and detected by the light microscope and significant pictures were saved by the digital camera. As a results of acute and chronic copper trials, edema, aneurism and serious degenerations of gills, necrosis and vacuolations in the hepatocytes and blood vessels of liver, and degenerations, granulamas and black spots in the spleen were indicated. It is detected that copper had vital effects on physiology of electric yellow cichlid and caused important tissue damages in fish.