Journal of Fishery Sciences of China (中国水产科学) 2013/20:6 PP.1247-1256
Takifugu obscures is a special economic species in China. Under the artificial aquaculture, the toxicity in this species decreases, which makes the fish consumption more widely than before. But the ability of anti-diseases decreases under aquaculture condition, which restricts the development of the aquaculture industry for this species. We used healthy juvenile specimens of T. obscures at body weight about 50 g. According to the requirement of this study we designed item trials with 3 replicates for each. The fish were administered β-glucans either by injection or orally (in feed). We subsequently experimentally infected each individual with Aeromonas hydrophila at various times after injection with β-glucan. We observed an increase in serum lysozyme (LZM), catalase (CAT), total serum protein (TSP), and superoxide dismutase (SOD) (P<0.05), but not complement 3(C3). Intraperitoneal injection of β-glucan significantly enhanced survival. Oral administration of β-glucan enhanced non-specific immunity (P<0.05), but had no effect on weight percent gain (WPG) and specific growth rate (SGR) (P>0.05). There was no difference in the non-specific immune response between groups that received continuous administration and those that received a single dose. Thus, we recommend use of a single injection to prevent immunological suppression.