Blood Chemistry, Antioxidants, Cytochrome P450 Activity and Hematological Properties of Clariagariepinus (African Catfish) Exposed to Heavy Metals (Copper and Lead Salts)

Abstract

— Fishes are one of the most important food resources and are considered as sources of the primary protein worldwide. Ongoing freshwater pollution increases the concentration of toxic metals in water and negatively affects fish health. These pollutants, which have a negative effect on fish, are released by agriculture, industrial wastewater discharge, raw sewage extraction, chemical waste, and oil spills due to fishing vessels. Waterborne metal exposure affects the physiological and biochemical factors in fish blood and tissues.The study investigated the changes in growth performance, hematological parameters, plasma components, and stress indicators of juvenile (African catfish) Clarias agriepinus, depending on varying exposures to copper and lead salts. In this study, 30 fish juveniles were engaged in each group of the five groups.C. agriepinus was exposed to the heavy metals at 20 and40 µg/l for first 15 and 30 days. Majority of the biomarkers such as GSH, catalase, cytP 450 , protein, blood glucose were measured spectrophotometrically. The results showed that Cu and Pb exposures resulted in decreased daily length gain (DLG), and daily weight gain (DWG). In terms of hematological parameters, white blood cells and red blood cell (RBC) count significantly decreased after 2 weeks and four weeks. Plasma enzyme components including transaminases and Cyt P 450 significantly increased. This work evidently demonstrated that at ecologically relevant concentrations, copper and lead can inhibit cellular functions of aquatic organisms. Most of the results obtained in this work were in line with some previous works.