Dietary supplementation with polysaccharides from Semen cassiae enhances immunoglobulin production and interleukin gene expression in early-weaned piglets

Forty piglets were used to determine the effect of 14-day dietary supplementation with polysaccharides from Semen cassiae (PSSA) on the immunity and interleukin (IL) gene expression in early-weaned piglets. Piglets were weaned at 21 days of age and four pigs were euthanized to provide the data at initial point. The remaining 36 pigs were fed the following corn- and soybean meal-based diets: the control diet (non-PSSA), the low-level PSSA diet (the control diet supplemented with 0.04% of PSSA), and the high-level PSSA diet (the control diet supplemented with 0.08% PSSA). Blood samples were collected on days 0 and 14, and lymph nodes on day 14 of the experimental period for the following measurements: IL-lp gene expression in blood mononuclear cells and jejunal mucosa; IL-2 gene expression in lymphatic nodes; serum levels of cytokines (IL-1 beta, IL-2, and IL-6); serum concentrations of immunoglobulins (IgA, IgG and IgM). Weaning stress resulted in decreases in serum antibody levels and cytoimmunity. Compared with the control group, dietary supplementation with a high level of PSSA increased: (1) serum concentrations of IL-1 beta, IL-2 and IL-6, as well as IgG, IgA and IgM; (2) expression of the IL-1 beta and IL-2 genes in blood mononuclear cells and lymphatic nodes; and (3) expression of the IL-1 beta gene in the jejunal mucosa. These novel findings suggest that polysaccharides from Semen cassiae enhance both the cell-mediated immune response and the humoral immunity in the early-weaned piglets. (c) 2007 Society of Chemical Industry.