726-732Immunostimulatory effect of leaf
extract of T. cordifolia on (i)
specific immunity (antibody response), (ii) non-specific immunity (neutrophil
activity) and (iii) disease resistance against Aeromonas hydrophila was investigated in
O. mossambicus. 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
A. hydrophila. The results indicates
the potential of T. cordifolia leaf
extracts for use as an immunoprophylactic to prevent diseases in finfish
aquaculture