Supplemental Bacillus subtilis DSM 29784 and enzymes, alone or in combination, as alternatives for antibiotics to improve growth performance, digestive enzyme activity, anti-oxidative status, immune response and the intestinal barrier of broiler chickens

Abstract

This study investigated the effect of Bacillus subtilis DSM 29784 (Ba) and enzymes (xylanase and β-glucanases; Enz), alone or in combination (BE) as antibiotic replacements, on the growth performance, digestive enzyme activity, immune response, and intestinal barrier of broiler chickens. In total, 1200 1-d-old broilers were randomly assigned to five dietary treatments, each with six replicate pens of 40 birds for 63 d as follows: A) basal diet (control), supplemented with B) 1×109 colony-forming units (cfu)/kg Ba, C) 300 mg/kg Enz, D) 1×109 cfu/kg Ba and 300 mg/kg Enz, and E) 250 mg/kg enramycin (ER). Ba, Enz, and BE, similar to ER, decreased the feed conversion rate, maintained intestinal integrity with a higher villus height-to-crypt depth ratio, and increased the numbers of goblet cells. The BE group exhibited higher expression of claudin-1 and Mucin-2 than the other four groups. BE supplementation significantly increased the α-diversity and β-diversity of the intestinal microbiota and markedly enhanced lipase activity in the duodenal mucosa. Serum endotoxin was significantly decreased in the BE group. Compared to those in the control group, increased superoxide dismutase and glutathione peroxidase activities were observed in the jejunal mucosa of Ba and BE groups, respectively. In conclusion, the results suggested that dietary treatment with Ba, Enz, or BE has beneficial effects on growth performance and anti-oxidative capacity, and BE had better effects than Ba or Enz alone on digestive enzyme activity and the intestinal microbiota. Ba or Enz could be used as an alternative to antibiotics for broiler chickens.

Effects of Bacillus amyloliquefaciens LFB112 on Growth Performance, Carcass Traits, Immune, and Serum Biochemical Response in Broiler Chickens

“…In the current study, B. amyloliquefaciens LFB112 substantially upregulated IgA and IgG concentrations in the serum of broilers on days 21 and 39, indicating an improvement in immune function. The results of this study are consistent with the research in which supplementation of Bacillus subtilis DSM 29,784 significantly upregulated serum IgA and IgG contents compared to the control or 250 mg/kg enramycin group [ 68 ]. Another report demonstrated that broilers receiving Saccharomyces boulardii and Bacillus subtilis B10 (1 × 10 8 CFU/kg of feed) significantly increased the number of IgA-positive cells in the jejunum, as well as the cytokine IL-6, TNF-α, TGF-β, and sIgA concentration levels in both jejunum and ileum [ 11 ].…”

Effects of Bacillus subtilis and Bacillus licheniformis on growth performance, immunity, short chain fatty acid production, antioxidant capacity, and cecal microflora in broilers

“…Moreover, up-regulated expression of IL-2 and IL-10 in the ileum was observed in an unchallenged experiment ( Park et al., 2020 ). The reason may be that B. subtilis or B. licheniformis could inhibit avian pathogenic growth and enhance functioning of the gut barrier ( Wang et al., 2017 ; Medina et al., 2019 ; Wang et al., 2020 ). Interestingly, based on our results, B. licheniformis was more effective than B. subtilis in increasing serum immunoglobulins and decreasing the pro-inflammatory cytokine, IL-6, further research is required to elucidate the exact, mechanism hereof.…”

The Potency of Bifidobacterium spp. as an Alternative to Antibiotic Growth Promoters on Feed Conversion Ratio, Feed Efficiency, and Nutrient Intake in Laying Hens

“…in this study significantly improved nutrient intake of protein, lipid, fiber, and organic matter. This can be due to increasing bacterial enzyme activity and increasing digestive enzyme activity, so there is improving nutrient intake, improving digestion, and nutrient absorption, which finally could improve the gut health status and production performance of chickens [25], [26], [27], [28], [29]. The microorganisms in feed supplements are generally regarded as safe (GRAS) and are important components of natural gastrointestinal tract microbiota.…”