Effect of Dietary Acanthopanax Senticosus Polysaccharide on Performance , Immunological , and Somatotropic Response in Piglets Challenged with Lipopolysaccharide

Major objective of the current study was to evaluate the effect of Acanthopanax senticosus polysaccharide (ASPS) on growth and immunological, somatotropic response of piglets challenged with lipopolysaccharide (LPS). A 2 × 2 factorial design including dietary treatment (0 or 800 mg/kg ASPS) and immunological challenge (LPS or saline injection) was conducted with 64 piglets assigned to two dietary treatments. Half of the piglets of per dietary treatment were injected with LPS or saline on day 14. Blood were obtained on day 2 after LPS challenge for lymphocyte proliferation and 3h after injection for analysis of IL-1, IL-6, TNF-α, PGE2, cortisol, GH, IGF-І and lgG. ASPS did not affect growth performance prior to LPS injection (P>0.05). From day 15 to 21, suppressed ADG and ADFI were observed by LPS(P<0.01). In contrast, ASPS improved these parameters (P<0.05), LPS and ASPS interaction was found on ADG and ADFI(P<0.05). Lymphocyte proliferation was promoted by LPS (P<0.01) or ASPS (P<0.05). but lgG was not affected (P>0.05) by ASPS or LPS throughout 21-day trial. ASPS depressed IL-1(P<0.05), IL-6(P<0.05), TNF-α(P<0.05) among LPS-treated piglets, ASPS and LPS interaction were observed on these indices(P<0.05). ASPS decreased PGE2 (P<0.05) and cortisol (P<0.05) concentrations as well as increased concentrations of IGFI (P<0.05) and GH (P<0.05) of LPS-treated piglets, and interaction between ASPS and LPS were observed for PGE2 (P<0.05), cortisol (P<0.05) and IGFI (P<0.05). This study suggest that ASPS mediated the release of pro-inflammatory cytokines and invoked pituitary hormone, PGE2 during immunological challenge period, which might enable pigs to achieve better performance.