Histopathological changes in liver and kidneys of cyprinid fishes due to water pollution in Kor River, Fars Province, Iran

Objective: Water pollution induces pathological changes in tissues of fish. As an indicator of exposure to contaminants, histopathology represents a useful tool to assess the degree of pollution, particularly for sublethal and chronic effects. The Kor River is one of the permanent rivers of the Fars Province of Iran that has been exposed to various contaminations such as heavy metals, because of existence of important industrial and agricultural centers around it. Heavy metals such as Pb, As, Hg and Cd accumulate in different tissues of fish and can have adverse effects. Therefore, the aim of present investigation was to study the histopathological changes in selected fish due to water pollution. Method & Materials: In this study, Kor River was divided into three zones, as upper zone (Doroodzan dam zone), mid zone (Band-e- Amir village) and lower zone (korbal village). From each zone, 10 fish were caught and after necropsy, samples of liver and kidneys were fixed in 10% buffered formalin, embedded in paraffin, sectioned at 5 μm, stained with hematoxylin and eosin (HE) and examined by light microscopy. Results & Conclusion: Histopathological changes in the liver were include congestion, cell swelling and vacuolar degeneration of hepatocytes, bile stagnation with canaliculi dilatation, hemosiderosis and deposit of hemosiderin pigment in the cytoplasm of kupffer cells, prevascular oedema and remarkable increase in the size and number of melano-macrophage centres; and in the kidneys, congestion, cell swelling and vacuolar degeneration of epithelial cells of tubules, oedema, hemorrhage, acute tubular necrosis, deposition of oxalate crystals and hyaline casts within tubules lumen. In these tissues, maximum histopathological changes were found in fish caught from mid zone of Kor River. According to the present results, it seems that water contamination in Kor River lead to induce microscopic changes in the liver and kidneys of fish.

کلیدواژه ها:

Histopathological lesions ، liver ، kidney ، water contamination ، fish