Location: Food and Feed Safety ResearchTitle: Oral treatment with ileal spores triggers immunometabolic shifts in chicken gut
|REDWEIK, GRAHAM - Iowa State University|
|Kogut, Michael - Mike|
|ARSENAULT, RYAN - University Of Delaware|
|MELLATA, MELHA - Iowa State University|
Submitted to: Frontiers in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/3/2020
Publication Date: 9/8/2020
Citation: Redweik, G.A., Kogut, M.H., Arsenault, R.J., Mellata, M. 2020. Oral treatment with ileal spores triggers immunometabolic shifts in chicken gut. Frontiers in Veterinary Science. 7: Article 629. https://doi.org/10.3389/fvets.2020.00629.
Interpretive Summary: The development of the immune response in chicks, pigs, and cows is controlled partly by the animal’s gut. This is because the gut is exposed not only to nutrients, but to many bacteria that can make the animals sick. What has been found over the last 20 years is that bacteria that do not cause disease but normally grow in the gut, can work together to make the animal’s immune system work better, and prevent bad bacteria from growing. We have identified a specific good bacteria in the gut of adult chickens that, when given to young chicks in their feed, can improve the immune system of the animal. This means the chick is less likely to get infected by bad bacteria that may be in the chicken house and allows the chick to grow up healthy. This paper is beneficial to chicken growers, microbiologists, and nutritionists to better understand and develop animal feeds which encourage the growth of the normal bacteria in the gut and aid in the development of a healthy immune system.
Technical Abstract: The animal gut is a major site affecting productivity via its role in mediating functions like food conversion and pathogen colonization. Segmented filamentous bacteria (SFB) are a keystone taxon that intimately binds to the animal intestine. In chickens, SFB naturally reach peak colonization by fourteen days post-hatch, but its colonization is not consistent between animals. In mammals, SFB are crucial in gut maturation, but their role in chicken health has not been experimentally studied yet. To test probiotic potential of SFB, we orally inoculated newly hatched chicks with small intestinal scrapings (SISs) with (iSFB) or without (CON) SFB. At 3, 7, and 14 days post-inoculation (dpi), gut permeability was measured via FITC-dextran assay in serum. Additionally, SISs were tested for in vitro Salmonella killing and total IgA. Lastly, distal ileum was either fixed or flash-frozen for microscopy or kinome peptide array, respectively. SFB were observed in the distal ileum in iSFB birds as early as 3 dpi and all birds at 7 and 14 dpi. At 3 dpi, iSFB birds exhibited lower gut permeability versus CON. In iSFB birds, SISs induced greater Salmonella growth at 3 dpi yet significantly reduced Salmonella load at 7 and 14 dpi compared to CON in an IgA-independent manner. Additionally, iSFB distal ileal tissue exhibited unique upregulation of several immunometabolic processes versus CON birds, including innate (Toll-like receptor, JAK-STAT) and adaptive (T/B cell receptor, TH17 differentiation) immune pathways, PI3K/Akt signaling, mTOR signaling, and insulin-related pathways. Altogether, these data suggest oral inoculation with SFB significantly improved gut health.