Dietary Ganoderma lucidum polysaccharides to enhance the growth, immune response and disease resistance of freshwater prawn Macrobrachium rosenbergii

Current study was made to investigate the effect of dietary Ganoderma lucidum polysaccharides (GLP) on growth, innate immune response and disease resistance of the freshwater prawn, Macrobrachium rosenbergii against Aeromonas hydrophila infection. Juveniles of M. rosenbergii were fed diets containing 0 (control), 1, 1.5, and 2 g/kg of GLP for a period of 15 days. At the end of the feeding experimental, survival, growth performance were significantly (P < 0.05) higher in 1.5 g/kg GLP supplemented feed fed prawns. The immune response and mortality were analysed in 5 day intervals post infection through 15 days of the feeding trial. Results showed that the cumulative mortality 15-days post-infection with A. hydrophila was significantly (P < 0.05) reduced in prawns fed with 1.5 g/kg GLP supplemented diets. The immune parameters, such as total hemocyte counts, phenoloxidase, transglutaminase activity and respiratory burst were found to be significantly (P < 0.05) higher in 1.5 g/kg of GLP supplemented diets fed prawns when compared to control diet fed prawns in all samplings days, while, the significant (P < 0.05) elevation was noted in phagocytic activity in 1.5 g/kg and 2 g/kg of GLP diets fed prawns. Also, hemolymph coagulation time was significantly (P < 0.05) decreased in 2 g/kg GLP supplemented diets fed prawns compared to control. Hence, these results suggest that GLP can be a promising dietary supplement for improving disease resistance of the freshwater prawns.