Protective effect of vitamin c on the variations in biochemical and histopathological parameters induced by copper in the teleost fish, anabas testudineus (bloch, 1792)

The toxic effects of copper and ameliorating capacity of vitamin C on biochemical and histopathological parameters in the teleost fish, Anabas testudineus were investigated. The 96 hour LC 50 value of copper was determined by Probit method and was found to be 1.74 mg/L. Fishes from two sub-lethal concentrations of copper, two vitamin supplemented and control media were analysed. The decreased (p ˃ 0.0001) haemoglobin (Hb), red blood cells(RBC) and oxygen carrying capacity(OC) up to 21st day depicted hypoxia with hypochromic, microcytic anaemia followed by the gradual increase on 28th day of exposure could be the symptom of restoration of aerobic respiration from copper induced anaerobia. The increase of plasma glucose, cortisol and LDH (lactate dehydrogenase) (p ˂ 0.0001) up to 21st day parallel to decrease in liver and muscle glycogen in both test concentrations and exposures justified hyperglycaemia due to glycogenolysis to combat high energy demand. Copper exposure induced obvious histopathological changes in gill architecture. Since gills are main route of metal uptake with extensive surface area interacting with toxic metal ions, the intensity of degenerative changes were more profound in copper intoxicated fishes. The symptoms of improvement of humoral and histological parameters in vitamin supplemented fishes reiterates the curative and prophylactic capacity of vitamin C.