Screening the Chicken Gut Microbiota for Species with Antimicrobial Properties

Abstract

The gut microbiota of chickens provides natural protection against pathogens through mechanisms like bacteriocin production. However, some enteropathogenic bacteria can disrupt the chicken gut microbiota, impair gut function, cause disease in the birds, and can be transmitted via the food chain to cause human infections. This study aimed to screen anaerobic chicken gut bacteria to detect species that have the most ability to inhibit the model enteric pathogens E. coli and Salmonella Typhimurium. Overlay and supernatant assays were used to assess inhibitory activity. The overlay assay results showed that three chicken gut strains, Bacteroides sp. [xylanisolvens/ovatus], Novel Lachnospiraceae strain, and Agathobaculum [massiliense], exhibited slight inhibition against both pathogens. Inhibition was less prominent in the supernatant assays, with only the non-chicken gut-derived control strain Bifidobacterium adolescentis significantly inhibiting pathogen growth. Short-chain fatty acid (SCFA) analysis found that the inhibitory Bifidobacterium adolescentis strain and the chicken gut strain Alistipes communis produced the greatest amount of acids, which might be linked to inhibitory activities Overlay assays were also used to assess potential unwanted commensal vs commensal inhibitory activities, and revealed that Alistipes communisinhibited other chicken gut bacteria. This work demonstrates that certain gut anaerobes may have potential as probiotics to combat enteropathogens, but further work is required to identify optimal candidates