Alfalfa Polysaccharide Enhances Growth Performance, Antioxidant Capacity, and Immunity in Weaned Piglets

The experiment aimed to investigate the effects of alfalfa polysaccharide on the growth performance, antioxidant capacity, and immunity of weaned piglets. Eighty weaned piglets, 30 days old, were randomly divided into four groups, with five replicates and four piglets in each replicate. The control group was fed the basal diet, while the low-concentration group was fed the basal diet supplemented with 1.0 g/kg of alfalfa polysaccharide. The medium concentration group received the basal diet with 2.0 g/kg of alfalfa polysaccharide, and the high-concentration group was fed the basal diet with 3.0 g/kg of alfalfa polysaccharide for a duration of 32 days.

The results revealed that the average daily weight gain of the medium and high concentration groups was significantly higher than that of the control group. In contrast, the daily feed intake and feed to weight ratio of the medium and high concentration groups were significantly lower than those of the control group (P<0.05). Moreover, compared to the control group, the activities of SOD, CAT, GSH-Px, and TAOC in the serum and liver were significantly higher in the medium and high concentration groups (P<0.05). Additionally, the activities of MDA were significantly lower in all three alfalfa polysaccharide groups compared to the control group (P<0.05).

Furthermore, the serum levels of IgA, IgM, and IgG were significantly higher in the medium and high concentration groups, while the serum levels of TNF-α and IL-6 were significantly lower in these groups compared to the control group (P<0.05). The mRNA expression of TNF-α in the high concentration group was significantly lower than that in the control group (P<0.05), and the mRNA expression of IL-10 in the medium and high concentration groups was significantly higher than that in the control group (P<0.05).

In conclusion, the study demonstrated that the addition of alfalfa polysaccharide improved the growth performance, antioxidant capacity, and immune response of weaned piglets. The optimal amount of alfalfa polysaccharide in this study was found to be 3.0 g/kg.