title: Comparative prevalence and characterization of ESBL-producing Enterobacteriaceae in dominant versus subdominant enteric flora in veal calves at slaughterhouse, France.
abstract: Food-producing animals have become a growing reservoir of Extended-Spectrum Beta-Lactamase (ESBL)-producing bacteria. In cattle, veal calves are exposed to high amounts of antibiotics but ESBL prevalence data are still limited compared to other food sectors such as poultry production. Based on the investigation of 491 veal calves from different slaughtering batches at 12 abattoirs, this study shows a prevalence of 29.4% of ESBL producers in the faecal flora of veal calves in France in 2012. A variety of blaCTX-M genes was found, reflecting possible diverse pathways of dissemination in cattle. Another major conclusion is the comparison of the ESBL prevalence in the dominant versus sub-dominant Escherichia coli population of the same calves (1% and 29.4%, respectively). Also, the ESBL E. coli clones in the sub-dominant flora mostly differed from the non-ESBL dominant E. coli clones of the same calves. Of note, the distribution of blaCTX-M genes and E. coli phylogroups were similar to the ones previously found in ESBL E. coli clones from diseased calves. The hypothesis that ESBL genes may distribute more abundantly in certain backgrounds of E. coli was also discussed. In all, as recently reported in the Netherlands, these results strongly suggest a recent increase in the prevalence of ESBL carriage in French veal calves, which should be considered one of the major ESBL reservoirs in food animals.
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France. Electronic address: marisa.haenni@anses.fr.
authors.forename: Marisa
authors.initials: M
authors.lastname: Haenni
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Châtre
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Métayer
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Maxime
authors.initials: M
authors.lastname: Bour
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Elodie
authors.initials: E
authors.lastname: Signol
authors.affiliation: Unité Antibiorésistance et Virulence Bactériennes, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Madec
authors.affiliation: Unité Epidémiologie, ANSES Site de Lyon, 31 avenue Tony Garnier, 69364 Lyon, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Gay
mesh_terms: D000003:Abattoirs; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005602:France / Q000453:epidemiology; D008460:Meat / Q000382:microbiology*; D015995:Prevalence; D013045:Species Specificity; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C048795:AmpC beta-lactamases; D001618:beta-Lactamases
keywords: Antimicrobial resistance; Cattle; ESBL; Healthy; Prevalence; Slaughterhouse