Dietary supplementation with Acanthopanax senticosus extract modulates cellular and humoral immunity in weaned piglets

This study was conducted to test the hypothesis that dietary supplementation with an herbal extract of Acanthopanax senticosus (AS) enhances the immune response in weaned piglets. Sixty piglets weaned at 21 days of age were randomly assigned to 3 treatment groups representing the addition of 0 or 1 g/kg of the AS extract or 0.2 g/kg of colistin (an antibiotic) to maize- and soybean meal-based diets (n = 20 per group). On days 7, 14 and 28 after initiation of the addition, total and differential counts of leucocytes, proliferating activity of peripheral lymphocytes, serum levels of immunoglobulins (Ig) and cytokines and the spleen index were determined. The AS extract decreased (p<0.05) the number of neutrophils on days 7 and 28 in comparison with the control group and reduced (p<0.05) serum interleukin- 1 beta level on day 28 compared with the other 2 groups. Dietary supplementation with the AS extract increased (p<0.05) the lymphocyte/leukocyte ratio on day 28 compared with the control group and increased the proliferating activity of lymphocytes on days 14 and 28 compared with the other 2 groups. The AS extract increased (p<0.05) the serum content of IgG on day 7 and of IgG and IgM on day 28 compared with the other 2 groups, as well as increasing the serum content of tumor necrosis factor on day 7 and spleen index on days 7 and 28 compared with the control group. Collectively, these findings suggest that the AS extract as a dietary additive enhances the cellular and humoral immune responses of weaned piglets by modulating the production of immunocytes, cytokines and antibodies.