The intestinal microbiota of conventional laboratory mice mediate strict colonisation resistance against C. jejuni. Therefore, the identification of intestinal bacteria and metabolites causing colonisation resistance combating C. jejuni and C. coli within the murine gut lumen will allow to develop novel therapeutic and/ or preventive strategies to complement biosafety measures directed against Campylobacter colonisation in farm animals and to abolish its transmission via established infection routes. Thus, we will investigate the gut microbiota, intestinal metabolites and corresponding host immune responses in mice applying metabolomic and microbiomic approaches. Given that our murine infection models mimic key features of human campylobacteriosis, investigation of the intestinal and systemic immune responses will be excellently suited to unravel immunopathogenic properties of C. coli in vivo for the first time. The collaborative experimental work within this unique consortium provides the exceptional opportunity to transfer corresponding findings directly into practice. Therefore, synthetic metabolites and/ or viable bacterial or fungal species conferring colonisation resistance against C. jejuni and/ or C. coli in mice will be evaluated for their preventive properties against colonisation of chicken, for practical transfer into food processing procedures and for suppression of enterocyte invasion or human infection in respective model systems established by the expert research partners. Finally, our murine infection models will be provided to the consortium in order to validate preventive or therapeutic measures and to provide data furthering the development to the pharmaceutical or product level.