Effects of copper on enzyme activity and accumulation of copper in blood tissues of Oreochromis niloticus exposed to copper and copper+EDTA complex

In this study, effects of copper on enzyme activity and accumulation in blood tissue of Oreochromis niloticus were investigated in both Cu and Cu+EDTA mixtures. The fish were exposed to 0.1 mg/L, 0.5 mg/L and 1.0 mg/L Cu and 0.1 mg/L Cu+0.3 mg/L EDTA and 0.5 mg/L Cu+3.0 mg/L EDTA and 1.0 mg/L Cu+3.0 mg/L EDTA mixtures for 7, 14 and 21 days to observe copper accumulation and serum enzyme in blood tissue.In this study, copper accumulation in blood tissue increased with increasing concentrations of copper in the medium and exposure period. In all the concentrations tested, copper accumulation in the blood tissue of fish exposed to Cu+EDTA mixtures were lower when compared to those exposed to copper only. In all conditions, EDTA significantly reduced the accumulation of copper in the blood of O. niloticus.In O. niloticus, serum enzymes were altered by exposure Cu and Cu+EDTA mixtures. In the blood tissues of fish exposed to Cu and Cu+EDTA mixtures were observed an increase in the activity of serum enzymes (LP, AST, LDH, ALP ve ALT).