Lycium barbarum Polysaccharides as Antibiotic Substitutes Improve Growth Performance, Serum Immunity, Antioxidant Status, and Intestinal Health for Weaned Piglets

Abstract

The aim of the present study is to investigate the effects of dietary Lycium barbarum polysaccharides (LBPs) supplementation on the growth performance, immune response, serum antioxidant status, and intestinal health of weaned piglets. In total, 24 crossed healthy weaned piglets [Duroc × (Yorkshire × Landrace)], of similar body weight (7.47 ± 0.22 kg), were randomly allocated to three treatment groups: CON (basal diet); LBPs (basal diet plus 4,000 mg/kg LBPs); and antibiotic (ABO, basal diet plus 20 mg/kg flavomycin and 50 mg/kg quinocetone). There were eight pigs per group. The study lasted 28 days. When compared with CON, LBPs or ABO dietary supplementation increased average daily gain (P < 0.05), decreased the ratio of feed to gain and the diarrhea ratio (P < 0.05). Similarly, when compared with CON, LBPs dietary supplementation increased serum immunoglobulin G, immunoglobulin M, interleukin-10, interleukin-2, and tumor necrosis factor-α levels (P < 0.05). Dietary LBPs enhanced the activity of serum total antioxidant capacity and glutathione peroxidase, and decreased malondialdehyde levels (P < 0.05). Principal component analysis showed a distinct separation between CON and LBPs groups, but no differences between ABO and LBPs groups. LBPs addition increased Lactobacillus and Faecalibacterium (P < 0.05) levels, while it decreased Enterococcaceae and Enterobacteriaceae (P < 0.05) levels. Furthermore, when compared with the CON group, LBPs increased villus height (P < 0.05) and the villus height to crypt depth ratio in the duodenum and jejunum (P < 0.05). Thus, dietary supplementation with LBPs improved growth performance, antioxidant capacity and immunity, regulated intestinal microbial composition, and may be used as an efficient antibiotic alternative in weaned piglet feed.

Keywords: Lycium barbarum polysaccharides; antioxidant; growth performance; immune; intestinal health; weaned piglets.

FIGURE 1

Diarrhea rate of weaned piglets fed MB dietary treatments (%) (n = 8). CON, basal diet; LBPs, basal diet + 4,000 mg/kg LBPs; ABO, basal diet + 20 mg/kg flavomycin + 50 mg/kg quinocetone. Asterisks express statistical differences between different groups: *P < 0.05.

FIGURE 2

Phylum-level relative abundance of 16S rRNA gene sequences from the cecal digesta of weaned piglets (n = 8). CON, basal diet; LBPs, basal diet + 4,000 mg/kg LBPs; ABO, basal diet + 20 mg/kg flavomycin + 50 mg/kg quinocetone.

FIGURE 3

Comparative analysis of 3 most relative abundances of gut microbiota (n = 8). Kruskal–Wallis test followed by Tukey test was used to evaluate the statistical significance. Asterisks express statistical differences between different groups: *0.01 < P ≤ 0.05, **0.001 < P ≤ 0.01, ***P ≤ 0.001. CON, basal diet; LBP, basal diet + 4,000 mg/kg LBPs; ABO, basal diet + 20 mg/kg flavomycin + 50 mg/kg quinocetone.

FIGURE 4

(A) Principal Component Analysis (PCA) of bacterial communities in the cecal digesta of weaned piglets (based on the Bray–Curtis distance) (n = 8). (B) Analysis of hierarchical clustering tree on Phylun level showed that the microbial composition of CON was almost entirely gathered in another branch. CON, basal diet; LBPs, basal diet + 4,000 mg/kg LBPs; ABO, basal diet + 20 mg/kg flavomycin + 50 mg/kg quinocetone.