title: Persistence and spread of qnr, extended-spectrum beta-lactamase, and ampC resistance genes in the digestive tract of chickens.
abstract: The aim of this assay was to develop an experimental model of digestive colonization of chickens with bacteria harboring qnr, extended-spectrum beta-lactamase, or ampC genes. Specific pathogen-free chickens were orally inoculated with two Escherichia coli strains containing either the plasmid pMG252 bearing bla(FOX) and qnrA genes, or pMG298 bearing bla(CTX-M) and qnrB genes. Analysis of strains isolated from fecal samples showed that the two strains were able to persist for several weeks in the digestive flora of inoculated birds and could rapidly spread to noninoculated ones. However, the multi-resistant isolates were maintained as a small proportion of the overall enterobacterial population. The qnr, extended-spectrum beta-lactamase, and ampC resistance genes could be transferred, in vivo, in the absence of selective pressure, to other chicken E. coli or Klebsiella pneumoniae isolates.
authors.affiliation: Anses, Laboratoire de Ploufragan-Plouzané, Unité Mycoplasmologie Bactériologie, Ploufragan, France.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Le Devendec
authors.forename: Axelle
authors.initials: A
authors.lastname: Bouder
authors.forename: Alexandra
authors.initials: A
authors.lastname: Dheilly
authors.forename: Gwenaëlle
authors.initials: G
authors.lastname: Hellard
authors.forename: Isabelle
authors.initials: I
authors.lastname: Kempf
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D002645:Chickens; D004195:Disease Models, Animal; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000235:genetics* / Q000302:isolation & purification; D029968:Escherichia coli Proteins / Q000235:genetics*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000235:genetics / Q000302:isolation & purification; D010957:Plasmids; D013997:Time Factors; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C485384:Qnr protein, E coli; C048795:AmpC beta-lactamases; D001618:beta-Lactamases