Immunomodulatory Effect Of Alginic Acid From Brown Seaweed Sargassum Wightii On Disease Resistance In Penaeus Monodon

In recent days, bacterial diseases are very common among all the aquatic organisms. Particularly in grow out ponds they cause heavy loss in aquaculture. To overcome this problem, the use of antibiotics become a common practice, thus leads to the development of antibiotic resistant strains. In this regard, a new attempt has been made to study the immunostimulatory effect of alginic acid, a sulphated polysaccharide derived from brown seaweed Sargassum wightii, on the disease resistance in Penaeus monodon. The immunological parameters, such as Total Haemocyte Count (THC), Prophenoloxidase activity, Respiratory burst (NBT assay), Superoxide dismutase activity and Phagocytic activity were monitored after challenging against Vibrio parahaemolyticus. Before the challenge study, the test animals were fed with different concentrations (1,2,3 g/kg as A1, A2, A3) of alginic acid fed diet for 45 days. All the immunological parameters showed a significant increase with an increasing concentration of alginic acid, in the test animals compared to the control throughout the experimental study period.