title: Antibiotics conspicuously affect community profiles and richness, but not the density of bacterial cells associated with mucosa in the large and small intestines of mice.
abstract: The influence of three antibiotics (bacitracin, enrofloxacin, and neomycin sulfate) on the mucosa-associated enteric microbiota and the intestines of mice was examined. Antibiotics caused conspicuous enlargement of ceca and an increase in overall length of the intestine. However, there were no pathologic changes associated with increased cecal size or length of the intestine. Conspicuous reductions in the richness of mucosa-associated bacteria and changes to community profiles within the small (duodenum, proximal jejunum, middle jejunum, distal jejunum, and ileum) and large (cecum, ascending colon, and descending colon) intestine occurred in mice administered antibiotics. Communities in antibiotic-treated mice were dominated by a limited number of Clostridium-like (i.e. clostridial cluster XIVa) and Bacteroides species. The richness of mucosa-associated communities within the small and large intestine increased during the 14-day recovery period. However, community profiles within the large intestine did not return to baseline (i.e. relative to the control). Although antibiotic administration greatly reduced bacterial richness, densities of mucosa-associated bacteria were not reduced correspondingly. These data showed that the antibiotics, bacitracin, enrofloxacin, and neomycin sulfate, administered for 21 days to mice did not sterilize the intestine, but did impart a tremendous and prolonged impact on mucosa-associated bacterial communities throughout the small and large intestine.
authors.affiliation: Agriculture and Agri-Food Canada Research Centre, Lethbridge Research Centre, Lethbridge, Alberta T1J 4B1, Canada.
authors.forename: Nathan J
authors.initials: NJ
authors.lastname: Puhl
authors.forename: Richard R E
authors.initials: RR
authors.lastname: Uwiera
authors.forename: L Jay
authors.initials: LJ
authors.lastname: Yanke
authors.forename: L Brent
authors.initials: LB
authors.lastname: Selinger
authors.forename: G Douglas
authors.initials: GD
authors.lastname: Inglis
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D007413:Intestinal Mucosa / Q000382:microbiology*; D007420:Intestine, Large / Q000382:microbiology* / Q000473:pathology; D007421:Intestine, Small / Q000382:microbiology* / Q000473:pathology; D054892:Metagenome / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S
chemical_list: D000900:Anti-Bacterial Agents; D012336:RNA, Ribosomal, 16S