Immunostimulatory effect of <i style="">Tinospora cordifolia</i> Miers leaf extract in <i style="">Oreochromis mossambicus</i>

Abstract

Immunostimulatory effect of leaf extract of <i style="">T. cordifolia</i> on (i) specific immunity (antibody response), (ii) non-specific immunity (neutrophil activity) and (iii) disease resistance against <i style="">Aeromonas hydrophila</i> was investigated in <i style="">O. mossambicus</i>. Ethanol and petroleum ether extracts of the leaves were used. Both ethanol and petroleum ether extracts administered at doses of 0.8, 8 or 80 mg/kg body weight, prolonged the peak primary antibody titres upto one to three weeks. Ethanol extract at the dose of 8 mg/kg and petroleum ether extract at the doses of 0.8 or 8 mg/kg enhanced the secondary antibody response. All the doses of ethanol extract significantly enhanced neutrophil activity. Fish injected with petroleum ether or ethanol extract at a dose of 8 mg/kg were protected against experimental infection with virulent <i style="">A. hydrophila</i>. The results indicates the potential of <i style="">T. cordifolia</i> leaf extracts for use as an immunoprophylactic to prevent diseases in finfish aquaculture.