title: Campylobacter jejuni colonization promotes the translocation of Escherichia coli to extra-intestinal organs and disturbs the short-chain fatty acids profiles in the chicken gut.
abstract: For a long time Campylobacter was only considered as a commensal microorganism in avian hosts restricted to the ceca, without any pathogenic features. The precise reasons for the symptomless chicken carriers are still unknown, but investigations of the gastrointestinal ecology of broiler chickens may improve our understanding of the microbial interactions with the host. Therefore, the current studies were conducted to investigate the effects of Campylobacter jejuni colonization on Escherichia coli translocation and on the metabolic end products (short-chain fatty acids, SCFAs). Following oral infection of 14 day old broiler chickens with 1 × 10(8) CFU of Campylobacter jejuni NCTC 12744 in two independent animal trials, it was found that C. jejuni heavily colonized the intestine and disseminate to extra-intestinal organs. Moreover, in both animal trials, the findings revealed that C. jejuni promoted the translocation of E. coli with a higher number encountered in the spleen and liver at 14 days post infection (dpi). In addition, Campylobacter affected the microbial fermentation in the gastrointestinal tract of broilers by reducing the amount of propionate, isovalerate, and isobutyrate in the cecal digesta of the infected birds at 2 dpi and, at 7 and 14 dpi, butyrate, isobutyrate, and isovalerate were also decreased. However, in the jejunum, the C. jejuni infection lowered only butyrate concentrations at 14 dpi. These data indicated that C. jejuni may utilize SCFAs as carbon sources to promote its colonization in the chicken gut, suggesting that Campylobacter cannot only alter gut colonization dynamics but might also influence physiological processes due to altered microbial metabolite profiles.Finally, the results demonstrated that C. jejuni can cross the intestinal epithelial barrier and facilitates the translocation of Campylobacter itself as well as of other enteric microorganisms such as E. coli to extra-intestinal organs of infected birds. Altogether, our findings suggest that the Campylobacter carrier state in chicken is characterised by multiple changes in the intestinal barrier function, which supports multiplication and survival within the host.
authors.affiliation: Clinic for Poultry and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria Department of Animal Hygiene, Poultry and Environment, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt wageha.awad@vu-wien.ac.at.
authors.forename: W A
authors.initials: WA
authors.lastname: Awad
authors.affiliation: Department of Animal Science and Animal Husbandry, Georgikon Faculty, University of Pannonia, Keszthely, Hungary.
authors.forename: F
authors.initials: F
authors.lastname: Dublecz
authors.affiliation: Clinic for Poultry and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria.
authors.forename: C
authors.initials: C
authors.lastname: Hess
authors.affiliation: Department of Animal Science and Animal Husbandry, Georgikon Faculty, University of Pannonia, Keszthely, Hungary.
authors.forename: K
authors.initials: K
authors.lastname: Dublecz
authors.affiliation: Clinic for Poultry and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Khayal
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Free University of Berlin, Berlin, Germany.
authors.forename: J R
authors.initials: JR
authors.lastname: Aschenbach
authors.affiliation: Clinic for Poultry and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Vienna, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Hess
mesh_terms: D000818:Animals; D018988:Bacterial Translocation; D002169:Campylobacter Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D016123:Campylobacter jejuni / Q000502:physiology*; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary; D002645:Chickens; D004926:Escherichia coli / Q000502:physiology*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D000069196:Gastrointestinal Microbiome / Q000502:physiology; D011201:Poultry Diseases / Q000382:microbiology* / Q000473:pathology
keywords: Campylobacter jejuni; Escherichia coli translocation; broiler chickens; intestinal colonization; microbial fermentation