Biochemical and histopathological alterations in Persian sturgeon, Acipenser persicus exposed to malathion

The present study was conducted to determine the toxicity induced by pesticide, malathion in Persian sturgeon, Acipenser persicus through assaying the plasma biochemical characteristics and histopathological alterations. For this purpose, three groups were exposed to sub-lethal concentrations of malathion (0.05, 0.1 and 0.2 median lethal concentration (LC50)) for 7 days and one control was considered (malathion-free group). Plasma levels of plasma total protein (TP) and globulin (GLOB) significantly decreased in exposed fish. The plasma levels of cortisol and glucose significantly elevated during exposure period in 0.2 LC50 group by the second day. Superoxide dismutase, glutathione-S-transferase, catalase, alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase activities showed dose- and time-dependent change pattern, with and the highest activity in 0.2 LC50 group by the second day. Alkaline phosphatase levels showed a dose- and time-dependent decrease in all experimental days. The plasma malondialdehyde levels significantly increased during exposure period. Different histopathological damages were observed in the gill, liver, and kidney of malathion-exposed fish. The degree of the histopathological alterations was varied from mild to very severe depending on malathion dosage. In conclusion, the results showed that plasma biochemical and histological parameters can be used as biomarkers of malathion pollution in A. persicus.