Tinospora cordifolia extract induced effects on cellular immune reactions of Labeo rohita (Hamilton) challenged against Aeromonas hydrophila.

Abstract

The present study was conducted to evaluate the effect of methanolic Tinospora cordifolia stem extract on cellular immune reactions of Labeo rohita fingerlings against Aeromonas hydrophila infection. Fish were fed with pelleted diet without Tinospora cordifolia stem extract (control), 100 mg (TC1), 200 mg (TC2) and 300 mg (TC3) methanolic stem extract of T. cordifolia kg-1 diet for 60 days. Immune reactions viz. NBT level, phagocytic activity, total immunoglobulin, lysozyme activity, antiprotease activity and myeloperoxidase activity of fish were examined at 0, 15, 30, 45 and 60 days of feeding. Fish were challenged with A. hydrophila after 60 days post feeding and relative percentage survible (%), immune reactions and agglutination antibody titre were recorded over 14 days post infection. The results demonstrated that fish fed with T. cordifolia stem extract showed enhanced NBT level, phagocytic activity, total immunoglobulin level, lysozyme activity, antiprotease activity and myeloperoxidase activity (p<0.05) compared with the control. The survival rate was higher in experimental diets than the control group. Dietary T. cordifolia stem methanolic extract at the level of 200 mg kg-1 showed significantly (p<0.05) higher protection (RPS 44.36±0.65%) and agglutination antibody titre (81.36±0.65) against A. hydrophila infection than control. The results suggest that the T. cordifolia stem methanolic extract have increases specific and non-specific immunity and disease resistance in L. rohita fingerlings against A. hydrophila infection.