University of Guilan Caspian Journal of Environmental Sciences 1735-3033 14 4 2016 12 01 Changes in biochemical and physiological responses of common carp, Cyprinus carpio L. after long-term exposure to Pb (II) 311 320 2073 EN S. Heidary Gorgan University A. Hajimoradloo Gorgan University A. Bani University of Guilan M. Aghamaali University of Guilan R. Ghorbani Gorgan University Journal Article 2016 05 01 In this study, the chronic toxic effects of Pb (II) on common carp, <em>Cyprius carpio</em> were  investigated using  several  biomarkers at different levels of biological functions for assessing changes in ecosystem quality. In a bioassay, common carp juveniles were individually exposed to different dose of heavy metal, Pb II (0, 0.45, 0.89, 1.34 mg.l^-1) for 28 days. Morphological indices such as hepatosomatic index, condition factor and lipid peroxidation (LPO) level and also the activities of superoxide dismutase  (SOD) and catalase (CAT) were measured. These results indicated that  there was significant lower condition factor in fish exposed to the highest concentration of Pb (p<0.05). The activity of hepatic antioxidant enzymes (SOD & CAT)  and LPO level was  significantly elevated after long-term exposure to higher concentration of Pb (p<0.05). Briefly, our findings suggested that common carp exposed to lead, develop oxidative stress, hence long-term exposure to higher concentrations of Pb could seriously affect the health status of fish. https://cjes.guilan.ac.ir/article_2073_113847e564e60f5d55dbe60d000696cb.pdf