This study investigated the effects of dietary supplementation with Bacillus subtilis ( B. subtilis ) or Bacillus licheniformis ( B. licheniformis ) on growth performance, immunity, antioxidant capacity, short chain fatty acid ( SCFA ) production, and the cecal microflora in broiler chickens. In total, 360 male, 1-day-old Cobb 500 birds were randomly divided into 3 groups: the control group was fed a basal diet; the B. subtilis group was fed a basal diet supplemented with 1.5 × 10 9 CFU/kg B. subtilis ; the B. licheniformis group was fed a basal diet supplemented with 1.5 × 10 9 CFU/kg B. licheniformis . Results showed that chickens supplemented with either B. subtilis or B. licheniformis had comparatively higher ( P < 0.05) body weight and average daily gain, whereas no difference ( P > 0.05) was observed in feed efficiency. Concentrations of serum IgA, IgY, and IgM, as well as anti-inflammatory IL-10 were significantly increased ( P < 0.05), and proinflammatory IL-1β and IL-6 were significantly decreased ( P < 0.05) by B. subtilis or B. licheniformis supplementation. Moreover, chickens fed with diets supplemented by either B. subtilis or B. licheniformis had greater antioxidant capacity, indicated by the notable increases ( P < 0.05) in glutathione peroxidase, superoxide dismutase, and catalase, along with decrease ( P < 0.05) in malondialdehyde. Compared to the control group, levels of SCFA, excluding acetic and propionic acid, in cecal content had improved ( P < 0.05) by adding B. licheniformis, and significant increase ( P < 0.05) in acetic and butyric acid was observed with B. subtilis supplementation. Microbial analysis showed that both B. subtilis or B. licheniformis supplementation could increase butyrate-producing bacteria such as Alistipes and Butyricicoccus , and decrease pathogenic bacteria such as the Synergistetes and Gammaproteobacteria . In summary, dietary supplemented with B. subtilis or B. licheniformis improved growth performance, immune status, and antioxidant capacity, increased SCFA production, and modulated cecal microbiota in chickens. Moreover, B. licheniformis was more effective than B. subtilis ...

The prebiotics inulin (INU) and isomalto-oligosaccharide (IMO) influence intestinal health and immunity, but their effects on constipation are not clearly established.

This experiment was conducted to evaluate the effects of astragalus polysaccharides (Aps) and ginseng polysaccharide (Gps) on growth performance, liver function, immune function, TLR4 signalling pathways and intestinal barrier in weaned piglets challenged with lipopolysaccharide (LPS). In an experiment spanning 28 days, 180 weaned piglets were randomly divided into three treatment groups: basal diet (Con), basal diet supplemented with 800 mg/kg Gps (Gps) and basal diet supplemented with 800 mg/kg Aps (Aps). At the end of the experiment, 12 piglets of each group were selected; half (n = 6) were intraperitoneally injected with LPS and half with normal saline. Dietary supplementation with Aps and Gps significantly increased (p < .05) the average daily gain and feed conversion rate. Lipopolysaccharide challenge increased (p < .05) expression of serum urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin‐1β (IL‐1β) and tumour inflammatory factor‐α (TNF‐α), but decreased (p < .05) serum superoxide dismutase (SOD) level, total antioxidant capacity (T‐AOC) and immunoglobulin A (IgA) expression. Lipopolysaccharide‐challenged piglets fed with Aps or Gps had lower (p < .05) BUN, ALT, AST, IL‐1β and TNF‐α levels and greater (p < .05) SOD, T‐AOC and IgA levels. Lipopolysaccharide challenge increased (p < .05) the expression of TLR4, MyD88 and NF‐κB, and LPS‐challenged piglets fed diets supplemented with Aps or Gps increased TLR4 and MyD88 and decreased NF‐κB expression. Lipopolysaccharide challenge reduced (p < .05) the jejunal villus height, and piglets fed with Aps or Gps had increased (p < .05) jejunal villus height. Supplementation with Aps or Gps enhanced the expression of occludin and claudin in challenged or unchallenged piglets. In conclusion, dietary supplementation with Aps or Gps enhanced piglet growth performance, alleviated liver dysfunction and reduced immunological stress caused by LPS, as well as increased the intestinal barrier function.

Several Bacillus strains exert beneficial effects on the maintenance of intestinal homeostasis and host health. However, whether Bacillus amyloliquefaciens (BA) can improve gut microbial dysbiosis and ameliorate colitis is unknown. Therefore, we conducted the present study to investigate the effects of BA administration on intestinal morphology, inflammatory response, and colonic microbial composition in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Results showed that BA administration significantly ameliorated body weight loss, decreased disease activity index, and improved colonic tissue morphology in DSS-treated mice. In addition, levels of immunoglobulins, as well as pro-inflammatory cytokines, were decreased after BA administration. Importantly, colonic microbiota profiling indicated a significant (p < 0.05) difference in beta-diversity between BA-administrated and DSS-treated mice, according to weighted principal coordinate analysis (PCoA) results. The relative abundance of the Firmicutes genus was increased, whereas that of Bacteroidetes was decreased by BA administration. Furthermore, phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis showed that the most significantly changed pathways between the four groups of mice were carbohydrate, lipid, and amino acid metabolism. In conclusion, our results showed that BA administration has beneficial effects on DSS-induced colitis, suggesting that this strategy might be useful for the treatment of dysbiosis during ulcerative colitis. Further, the changes in metabolism, especially amino acid metabolism, might contribute to the beneficial effects of BA on the amelioration of DSS-induced colitis.

This study was conducted to determine the effects of dietary addition of α-glyceryl monolaurate ( α-GML ) on growth performance, immune function, volatile fatty acids production and cecal microbiota in broiler chickens. A total of 480 1-day-old yellow-feathered broilers were randomly assigned in equal numbers to 4 dietary treatments: basal diet ( NCO ) or supplementations with 30 mg/kg bacitracin ( ANT ), 500 mg/kg α-GML, or 1,000 mg/kg α-GML ( GML2 ). And, each treatment contained 8 replicates with 15 chickens per replicate. After supplementation with α-GML, the total BW gain and average daily weight gain of broilers increased significantly ( P < 0.05) compared with the broilers on the NCO diet. Moreover, compared with the NCO group, higher levels of immune globulin M and immune globulin Y were observed in both GML groups and the ANT group. Concentrations of acetate, propionate, butyrate, valerate, and isovalerate in GML2 were significantly higher ( P < 0.05) than those in the NCO group on day 28. However, acetate, propionate, valerate, and isovalerate concentrations were reduced to significantly ( P < 0.05) lower than those in the NCO group on day 56. The abundance and diversity of microbiota were found to be improved in broilers that were supplemented with GML, using operational taxonomic unit and diversity analyses. Furthermore, the GML treatments increased favorable microbiota, particularly acid-producing bacteria, on day 28 and, also, reduced opportunistic pathogens, such as Alistipes tidjanibacter and Bacteroides dorei by day 56. These results suggest that α-GML supplementation modulates cecal microbiota and broiler immunity and improves volatile fatty acid levels during the early growth stages of broilers.