Generation of superoxide anion and SOD activity in haemocytes and muscle of American white shrimp (Litopenaeus vannamei ) as a response to β-glucan and sulphated polysaccharide

Juvenile American white shrimp (Litopenaeus vannamei) were immersed in aerated β-glucan and sulphated polysaccharide solutions for 1, 3 and 6 h. Superoxide anion and SOD activity in haemocytes and muscle were investigated to evaluate whether β-glucan and sulphated polysaccharide induce any immunostimulatory activity. Haemocytes and muscle showed different levels of superoxide anion generation and SOD activity (2·0 and 1·4 times that of control, respectively) when shrimp were immersed for 6 h in aerated sea water containing β-glucan and sulphated polysaccharide. haemocyte count (THC) decreased within the first 24 h after challenge with immunostimulants, but THC and total soluble haemocyte protein increased over normal values after 48–120 h. immunostimulation with β-glucan and sulphated polysaccharide is capable of generating an increase in the respiratory burst of L. vannamei haemocytes.