Effect of dietary β-glucan on histopathology of liver and gills against toxicity of copper sulfate in Cyprinus carpio L.

Abstract

The objective of this study was to determine the protective effect of β-glucan against the impact of copper (Cu) toxicity on histopathological changes in common carp Cyprinus carpio L. which exposed to different level of Cu for 96h and also to assess the effect of addition β-glucan to the fish diet against Cu toxicity. Fish (150 ± 2g) were divided randomly into eight groups as follows: C1 were fed commercial diet; C2 were fed commercial diet with 1%β-glucan; T1 were fed diet without β-glucan and exposed to 5 mg l-1 to CuSO4; T2 were fed diet with 1% β-glucan and exposed to 5 mg l-1 to CuSO4; T3 were fed diet without β-glucan and exposed to 7 mgl-1 to CuSO4; T4 were fed diet with1%t β-glucan and exposed to 7mg l-1 to CuSO4; T5 were fed diet without β-glucan and exposed to 9 mg l-1 to CuSO4; T6 were fed diet with1% β-glucan and exposed to 9 mg l-1 to CuSO4 for 96 h. The main histopathological changes including: hepatic vacoulation, necrosis, accompanied with hemorrhage, congestion of blood vessels and sinusoids. While the gills lesions revealed ulceration of rakers mucosal epithelia, lifting of lamellar epithelia and aneurysms (telangiectasia) of secondary lamella and lamellar fusion caused by the filament epithelium proliferation together with mononuclear infiltration. The result of this study suggested that the addition of β-glucan in fish diet reduced Cu toxicity. Also, the result indicated that the supplementation of β-glucan provided protection against the degenerative action of Cu and increased the chance of tissue regeneration