The regulation effect of Atractylodis macrocephalae polysaccharides on the growth performance, antioxidant capacity and immune function in Litopenaeus vannamei

This study aims to investigate the effects of Atractylodis macrocephalae polysaccharides (AMP) on the growth performance, antioxidant capacity and non-specific immune function in Litopenaeus vannamei. Accordingly, three experimental diets including 0 (control group), 0.05% and 0.5% AMP were formulated and fed for 3 weeks. The result showed that compared with the control group, dietary 0.5% AMP supplementation significantly increased the weight gain (P < 0.05), serum biochemical indices (albumin, glutamate-pyruvate transaminase, glutamate-oxalacetate transaminase, glucose, triglyceride and total cholesterol) while 0.05% AMP supplementation had no significant influence on the above index (P > 0.05). Dietary 0.05% and 0.5% AMP supplementation significantly increased total antioxidant capacity (P < 0.05), superoxide dismutase, and glutathione peroxidase in tissues (hemolymph, hepatopancreas and intestine) while there was a decreasing trend on the malondialdehyde content with the increased AMP supplementation (P < 0.05). Tissue lysozyme, alkaline phosphatase, acid phosphatase and total nitric oxide synthase content were significantly increased with increased AMP levels in the diets and reached the highest values in the 0.5% AMP supplementation group (P < 0.05). Similar trends were observed in the further antioxidant and immune-related gene expression analysis. Gene expression of inflammatory signaling pathways (toll-like receptor 4/myeloid differentiation factor 88) and inflammatory cytokines (Tumour necrosis factor-α, apoptosis-inducing factor, member RAS oncogene family) was reduced with AMP supplementation in the diets. In conclusion, dietary AMP supplementation could improve growth performance, antioxidant ability and immune function in shrimp, and recommended dosage for safety was 0.05%.