Comparative toxicological effects of diet and water borne lead on blood biochemical changes of common carp (Cyprinus carpio)

Heavy metals can enter to the aquatic animal's body through dietary or water sources and exert their harmful effects. This study was conducted to compare the toxicity of lead in common carp via diet and water borne conditions. Total number of 135 fish (average weight of 50±10 g) was divided into three groups (each with triplicate) including control, water borne (1 mg/L) and diet borne (1 mg/kg dry diet) lead. Experiment was executed during 21 days and sampling was done at 7, 14 and 21 days after trial initiation. Blood biochemical factors including total protein, albumin, globulin, creatinine, glucose, cholesterol, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured in mentioned sampling times. Results showed that lead exposure led to negative effects on blood biochemistry in both groups, but in the case of glucose, LDH and ALP, significant changes were observed between diet and waterborne lead. It may conclud that the diet borne had more toxic effects than waterborne lead and therefore, lead had more potential toxicity through diet in common carp.