Submitted to: Federation of European Microbiological Societies Microbiology Ecology
Publication Type: Review Article
Publication Acceptance Date: 9/22/2006
Publication Date: 4/20/2007
Citation: Scupham, A.J. 2007. Succession in the intestinal microbiota of pre-adolescent turkeys. Federation of European Microbiological Societies Microbiology Ecology. 60(1):136-147.
Interpretive Summary: Campylobacter is the primary cause of bacterial food-borne disease and poultry is the predominant source of this pathogen for human infection. An understanding of Campylobacter ecology in the poultry intestine is necessary for development of interventions, however tools for analysis of microbial ecology in the intestinal tract have only recently been developed. In this work, development of the turkey intestinal microbiota was examined to identify periods of community transition, and thus susceptibility to Campylobacter colonization. One such transition was identified in the period of 11-12 weeks of age. Communities predominated by Clostridiales were supplanted by an overgrowth of Bacteroides uniformis, followed the next week by increased Clostridiales and Bacteroidetes diversity and stabilization of the microbial communities. Up to an eight-log increase in Campylobacter quantities correlated to the transition, suggesting a relationship between community instability and colonization by food-borne pathogens. This work suggests host-derived signals strongly affect intestinal microbiota. It also identifies a potential critical control point late in turkey production that may be exploited to protect turkeys from contamination by food-borne pathogens.
Technical Abstract: Molecular ecology of the gut is a recent area of study with great potential for making advances in the areas of medicine, animal health and food safety. In this work we used Automated Ribosomal Intergenic Spacer Analysis (ARISA), real-time PCR detection of Bacteroides uniformis and Campylobacter coli as well as sequence library analysis to identify trends in microbial colonization of the ceca of male turkeys. Two separate trials were performed with 6 and 5 birds, respectively. ARISA community profiles identified a period of community transition at week 12 of age in both trials. A significant increase of Campylobacter coli was also detected at week 12, suggesting a correlation between microbiota destabilization and pathogen prevalence. Bacterial libraries representing weeks 9, 11, 12 and 14 were sequenced. While fingerprint and sequence analyses indicated significant differences in the species composition between the two trials, a predominance of Clostridia-like species was replaced by a predominance of Bacteroides-like species in both cases. B. uniformis prevalence at week 11 was 84% and 79% of the library clones for the two trials respectively. Real-time PCR quantification corroborated the sequence library data. This finding provides evidence that Bacteroides uniformis or other Bacteroides species may act as a vanguard, preparing the gut environment for colonization by other Bacteroides species.