Document Type : Primary Research paper
This investigation was intended to test the possible protective role of taurine and garlic extract against the toxicity of copper sulphate to Clarias gariepinus. For this purpose experiment was setup in seven groups (I-VII) containing 20 fish in each group. The fish of group I were kept as control. The fish of groups of II, IV and VI were challenged with 4 ppm solution of copper sulphate, where as groups III, V and VII were exposed to 8 ppm copper sulphate. Simultaneously, groups II and III were maintained as copper sulphate exposed non antioxidant treated control whereas, groups IV and V were treated with taurine (5 ppm) and groups VI and VII were treated with garlic extract (5 ppm) during the entire experiment period of 90 days. Histopathological observation of the gills after 15, 30, 60 and 90 days on exposure of sublethal copper sulphate concentrations revealed severe histopathological changes including, lamellar epithelium lifting, disintegration in pillar cell system with formation of aneurysms, increased infiltration of erythrocytes and leucocytes, haemolysis and haemorrhage, hyperplasia, complete fusion of secondary lamellae. While as addition of garlic extract and taurine has comparatively minimized histopathological alterations in groups VI and VII, respectively. It seems that simultaneous exposure of fish to taurine or garlic extract with copper sulphate were found to partly mitigate its toxicity indicating their potential therapeutic activity against copper toxicity in fish.