Effects of subchronic exposure to Spartakus (prochloraz) on common carp Cyprinus carpio.

OBJECTIVES: The aim of the study was to investigate effects of the fungicide formulation Spartakus (prochloraz 450 g.L-1) on common carp Cyprinus carpio through biometric, biochemical, haematological and antioxidant indices, induction of xenobiotic metabolizing enzymes and histological examination of selected tissues.

DESIGN: The test was performed on juvenile fish, which was exposed to Spartakus (concentrations of prochloraz: 0.05; 0.15 and 0.38 mg.L-1) for 28 days. Haematological indices were assessed using unified methods of haematological examination in fish. Plasma biochemical indices were determined by biochemical analyzer. Concentration of total cytochrome P450 (CYP), glutathione (GSH) content and glutathione-S-transferase (GST) activity were determined spectrophotometrically in hepatopancreas. Activity of liver ethoxyresorufin-O-deethylase (EROD) activity was measured spectrofluorimetrically. Ferric reducing ability of plasma (FRAP) and ceruloplasmin activity were assessed spectrophotometrically. Histological changes in samples of hepatopancreas, skin, gills, spleen, head kidney and caudal kidney were examined by light microscopy.

RESULTS: There was a significant rise in hepatosomatic index (HSI) (p<0.01), CYP and EROD (p<0.05) of fish exposed to prochloraz of 0.15 and 0.38 mg.L-1 whereas GST was induced by all concentrations tested and GSH by 0.38 mg.L-1 (p<0.05). Red blood cell count decreased significantly (p<0.05) in prochloraz of 0.05 and 0.15 mg.L-1. Plasma potassium increased (p<0.01) in all Spartakus treated groups, a decline in total protein (p<0.05), ALT, Na+ and Ca (p<0.01) was found in fish exposed to prochloraz of 0.38 mg.L-1. Ceruloplasmin activity was elevated (p<0.05) in the highest concentration tested, FRAP declined (p<0.05) in the same group. Histopathological changes in gills were demonstrated in all pesticide treated groups, with a decreased activity of skin mucous cells in prochloraz of 0.38 mg.L-1.

CONCLUSION: The subchronic exposure to Spartakus influenced HSI, induced xenobitic metabolizing enzymes, initiated a disorder of selected plasma indices and a decline in red blood cell count, caused minor histological impairment, and affected antioxidant activities of the test fish.