Evaluation of immune responses in an Indian carp, Labeo rohita (Hamilton) fed with levamisole incorprated diet

Abstract

Effects of oral administration of  levamisole on the selected components of the immune system of an Indian carp,  Labeo rohita, were evaluated with a view in assessing the potential of using this compound as an immunostimulant in culturing this fish. Sub-adults of L. rohita were fed with levamisole incorporated diet (5 mg kg-1 body weight),  on the first day and every third day for 16 days (6 doses) and effects on haematocrit, total and differential leucocyte counts, phagocytic activity, production of oxygen radicals from phagocytes in the blood, lysozyme activity in the serum, total protein and immunoglobulin levels in the blood plasma were assessed at different time points in comparison to the levels of controls. Results showed that the populations of total leucocytes, neutrophils, monocytes and lymphocytes were elevated significantly on 14 and 21 days post levamisole treatment. In addition, total phagocytic activity, phagocytic index and lysozyme activity of the fish blood were enhanced significantly on 21 days post treatment.  Results support the potential use of levamisole as an immunostimulant in culturing this fish. Keywords: Labeo rohita; levamisole; immunostimulant; Indian carp DOI: 10.4038/josuk.v3i0.2735J. Sci. Univ. Kelaniya 3 (2007) : 17-28