Effects Of Polysaccharide On The Immune Function And Growth Of Macrobrachium Nipponense

Macrobrachium nipponense were fed with diet containing 1 Polystictus polysaccharide and Cordyceps polysaccharide, the phagocytic activity in the hemocytes, the antibacterial activity, bactericidal activity and phenoloxidase activity in the hemolymph of M.nipponense were continuously measured in order to detect the effect of two kinds of polysaccharide on the immune effect of M.nipponense. The results were as follows:1) Polystictus polysaccharide and Cordyceps polysaccharide can significantly strength the phagocytic activity in the hemocytes of M.nipponense . when the water temperature was above 10(such as in Spring, in Summer and in Autumn), the phagocytic percentage and the phagocytic index of test groups were significantly higher than control group, on the contrary, when the water temperature was below 10(such as in Winter), there were not remarkably difference among test groups and control group.2) Polystictus polysaccharide and Cordyceps polysaccharide can enhance not only celluar immunity but also humoral immunity . In most cases, the antibacterial activity, bactericidal activity and phenoloxidase activity in the hemolymph of test groups increased, therefore Polystictus polysaccharide and Cordyceps polysaccharide can be used as non-special immunopotentiator to enhance the immune function of M.nipponense.3) Polystictus polysaccharide and Cordyceps polysaccharide have effecton the growth and the survival rate of M.nipponense. After feeding with polysaccharide for two months, the average length gain rate of Polystictus group, Cordyceps group and control group was respectively 45.74%, 40.19%and25.61%. The average weight gain rate of Polystictus group, Cordyceps group and control group was respectively 64.19%, 63.43% and 36.86. The total weight gain of Polystictus group, Cordyceps group and control group was respectively 78.91, 76.89 and -23.55. The survival rate of Polystictus group, Cordyceps group and control group was respectively 96.15%, 96.1% and 58.54%.The above results showed that Polystictus polysaccharide and Cordyceps polysaccharide could improve nonspecific immunity of M.nipponense, and increase their adaptability to environment.