This study tested the effect of distillers dried grains with soluble (DDGS) inclusion in a broiler diet, with or without supplementation of exogenous enzymes, on the microbiota composition, intestinal health, diet digestibility and performance. A total of 288 one-day-old chickens was assigned to 6 treatments (8 replicate of 6 birds each) according to a completely randomized design with a 3 × 2 factorial scheme with 3 DDGS levels (0, 7 and 14%) and 2 inclusions of exogenous enzymes (with or without a multicarbohydrase complex + phytase [MCPC]). The results exhibited that DDGS inclusion up to 14% did not impair broilers performance up to 28 d, however, DDGS-fed animals exhibited significant improvement with the MCPC supplementation. No effects of the enzymes in the ileal digestibility were found at 21 d. DDGS inclusion in the diet affected dry matter and gross energy digestibility. Broilers fed diets with MCPC were found to have less intestinal histological alteration thus better gut health. No effect of DDGS, enzyme or interaction of those were observed for intestinal permeability and in the serum inflammatory biomarker (calprotectin) at 7 and 28 d. The increase of DDGS percentage in the diet reduced the diversity of the ileal microbiota but increased the cecal microbiota diversity. The inclusion of DDGS showed positive effects on microbiota composition due to a reduction of Proteobacteria phylum in the ileum at 28d and a reduction in the presence of Enterococcaceae family in the ileum at 14 and 28d. The inclusion of MCPC complex might promote beneficial changes in the ileal and cecal microbiota due reduce of Proteobacteria, Bacillaceae and Enterobacteriaceae. The supplementation of xylanase, β-glucanase, arabinofuranosidase and phytase to a DDGS diet improves performance and intestinal health allowing the use of these subproduct in the poultry nutrition.

As the demand for alternatives to antibiotic growth promoters (AGP) increases in food animal production, phytobiotic compounds gain popularity because of their ability to mimic the desirable bioactive properties of AGP. Chestnut tannins (ChT) are one of many phytobiotic compounds used as feed additives, particularly in South America, for broilers because of its favorable antimicrobial and growth promotion capabilities. Although studies have observed the microbiological and immunologic effects of ChT, there is a lack of studies evaluating the metabolic function of ChT. Therefore, the objective of this study was to characterize the cecal metabolic changes induced by ChT inclusion and how they relate to growth promotion. A total of 200 day-of-hatch broiler chicks were separated into 2 feed treatment groups: control and 1% ChT. The ceca from all the chicks in the treatment groups were collected on day 2, 4, 6, 8, and 10 after hatch. The cytokine mRNA quantitative RT-PCR was determined using TaqMan gene expression assays for IL-1B, IL-6, IL-8, IL-10, and interferon gamma quantification. The cytokine expression showed highly significant increased expressions of IL-6 and IL-10 on day 2 and 6, whereas the other proinflammatory cytokines did not have significantly increased expression. The results from the kinome array demonstrated that the ceca from birds fed with 1% ChT had significant (P < 0.05) metabolic alterations based on the number of peptides when compared with the control group across all day tested. The increased expression of IL-6 appeared to be strongly indicative of altered metabolism, whereas the increased expression of IL-10 indicated the regulatory effect against other proinflammatory cytokines other than IL-6. The ChT initiate a metabolic mechanism during the first 10 d in the broiler. For the first time, we show that a phytobiotic product initially modulates metabolism while also potentially supporting growth and feed efficiency downstream. In conclusion, a metabolic phenotype alteration in the ceca of chickens fed ChT may indicate the importance of enhanced broiler gut health.

Previous studies have shown a tissue immune phenotype-altering event occurring on days 2 and 4 in the ceca post-Salmonella challenge. To evaluate the involvement of the cecal microbiota in the phenotype reprogramming, we hypothesized that the addition of subtherapeutic bacitracin (BMD) will affect the cecal microbiota. Therefore, the objective of this study was to determine if the antibiotic-mediated changes in the microbiota composition influenced the immune phenotype induced by Salmonella enteritidis infection of the chicken cecum. A total of 112 fertile eggs were obtained for each experiment, repeated for a total of three separate times. The ceca and cecal contents were collected on days 2 and 4 post-infection for mRNA expression TaqMan assay and 16S rRNA gene microbiota sequencing. The results demonstrate the effects of bacitracin on cecal composition and its interaction with Salmonella enteritidis in young chicks. There is a preliminary indication of phenotype change in the Salmonella-challenged group provided subtherapeutic BMD due to the shifting cecal microbiota and cecal immune response, indicating the addition of bacitracin during infection altered the cecal phenotype. These data demonstrate the potential involvement of the microbiota in reprogramming immune phenotype (disease resistance to disease tolerance) induced by Salmonella in the chicken cecum.

In the past decade, the withdrawal of antibiotics used as growth promoters (AGP) has increased some poultry industry challenges, such as the rise of intestinal diseases. Experts advocate that AGPs improve performance due to the modulation of the intestinal microbiota, with resulting anti-inflammatory effects. However, the impact and interactions of AGPs with the host intestinal immune system are still unknown, which represents issues in developing effective alternatives for AGPs. Therefore, this study was aimed at better understanding the potential mechanism of action of bacitracin used as AGP and its impacts on the intestinal immune system. Ninety day-of-hatch chickens were randomly assigned to two treatments with three repetitions of fifteen birds, a control (CNT) group with a corn/soybean meal standard diet, and a control diet supplemented with 50 g/ton of feed of bacitracin (BMD). The cytokines’ and chemokines’ production (IFN-α, IFN-γ, IL-16, IL-10, IL-21, IL-6, M-CSF, MIP-3α, MIP-1β, VEGF and CCL-5) were assessed in the jejunum and ileum at 14, 21, 28 and 36 days of age by using a chicken-specific cytokine/chemokine peptide ELISA array. Broilers with BMD supplementation were found to have a lower production of IL-16, IFN-γ, M-CSF, IL-21, MIP-1β and VEGF in the jejunum at 14 d. However, from 21 through 36 days, the effect of BMD on cytokine production in the jejunum was negligible except for CCL-5, which was reduced at D36. In the ileum, BMD effects on the cytokine profile started at 28 d, when BMD-supplemented broilers showed a reduced IL-6 production level. At day 36, BMD reduced IL-16 and MIP-3α production but increased VEGF concentration in the ileum tissue. The present study demonstrated that the use of bacitracin as an AGP modulates the small intestine immune system, especially in the first phase of the broiler’s life (up to 14 days). Moreover, BMD anti-inflammatory effects include not only innate immunity but also seemed to influence the development of the adaptive immune response as seen by the decreased production of IL-21 and IL-16. These results demonstrate that a commonly used AGP in broiler feed had a local anti-inflammatory effect.

Background As the demand for alternatives to antibiotic growth promoters (AGPs) increases in food animal production, phytobiotic compounds gain in popularity due to their ability to mimic the desirable bioactive properties of AGPs. Chestnut tannins (ChT) are one of many phytobiotic compounds utilized as feed additives, particularly in South America, for broiler chickens due to its favorable antimicrobial and growth promotion capabilities. While studies have observed the microbiological and immunological effects of ChT, there is a lack of studies evaluating the metabolic function of ChT in the host. Therefore, the objective of this study was to characterize the cecal metabolic changes induced by ChT inclusion and how they relate to growth promotion. Results A total of 500 day-of-hatch Cobb 500 chicks were separated into five feed treatment groups: control, 1% ChT, 0.2% ChT, 0.08% ChT, and 0.03% ChT. The cecas from all the chicks in the treatment groups were collected on days 2, 4, 6, 8, and 10 post-hatch. The cytokine mRNA qRT-PCR was determined using TaqMan gene expression assays for IL-1B, IL-6, IL-8, IL-10, and IFN-γ quantification. The cytokine expression showed highly significant increased expressions of IL-6 and IL-10 on days 2 and 6, while the other pro-inflammatory cytokines did not have significantly increased expression. The results from the kinome array demonstrated that the cecas from birds fed with 1% ChT had significant (p < 0.05) metabolic alterations based on the number of peptides when compared to the control group across all days tested. Conclusions Based on the results, the increased expression of IL-6 appeared to be strongly indicative of altered metabolism while the increased expression of IL-10 indicated the regulatory effect against other pro-inflammatory cytokines other than IL-6. The ChTs initiate a metabolic mechanism during the first ten days in the broiler. For the first time, we show that a phytobiotic product initially modulates metabolism rather than immunity while also potentially supporting growth and feed efficiency downstream. In conclusion, an IL6-mediated immunometabolic phenotypic alteration in the ceca of chickens fed ChT may indicate the importance in the gut of enhanced broiler health.