title: Low Occurrence of Extended-Spectrum β-lactamase-Producing Escherichia coli in Finnish Food-Producing Animals.
abstract: ESBL/AmpC-producing Escherichia coli is increasingly isolated from humans and animals worldwide. The occurrence of ESBL/AmpC-producing E. coli was studied in food-producing animals in Finland, a country with a low and controlled use of antimicrobials in meat production chain. A total of 648 cattle, 531 pig, 495 broiler and 35 turkey faecal samples were collected from four Finnish slaughterhouses to determine the presence of extended-spectrum β-lactamase (ESBL/AmpC)-producing E. coli. In addition, 260 broiler and 15 turkey samples were screened for carbapenemase-producing E. coli. Susceptibility to different class of cephalosporins and meropenem was determined with disc diffusion tests according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Determination of ESBL/AmpC production was performed with a combination disc diffusion test according to the recommendations of the European Food Safety Authority (EFSA). Plasmidic blaESBL/AmpCgenes were characterized by polymerase chain reaction and sequencing. A collection of isolates producing AmpC enzyme but not carrying plasmidic blaAmpCwas analysed by PCR and sequencing for possible chromosomal ampC promoter area mutations. Altogether ESBL/AmpC-producing E. coli was recovered from five cattle (0.8%), eight pig (1.5%) and 40 broiler samples (8.1%). No ESBL/AmpC-producing E. coli was found in turkey samples. Carbapenem resistance was not detected. Altogether ESBL/AmpC-producing E. coli was found on 4 (2.0%), 3 (4.5%) and 14 (25%) cattle, pig and broiler farms, respectively. From cattle samples 3 (27%) blaCTX-M-1and from broiler samples 13 (33%) blaCTX-M-1and 22 (55%) blaCMY-2gene-carrying isolates were detected. In pigs, no plasmidic blaESBL/AmpCgene-carrying isolates were found. In all analysed isolates, the same mutations in the promoter region of chromosomal ampC were detected. The results showed low occurrence of ESBL/AmpC-producing E. coli in Finnish food-producing animals. In pigs, plasmidic blaESBL/AmpC-carrying E. coli was not detected at all.
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Päivärinta
authors.affiliation: Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
authors.forename: L
authors.initials: L
authors.lastname: Pohjola
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Fredriksson-Ahomaa
authors.affiliation: Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Heikinheimo
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005387:Finland / Q000453:epidemiology; D005516:Food Microbiology; D006801:Humans; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases
keywords: 
  Escherichia coli
  ; AmpC; ESBL; broiler; carbapenemase; food-producing animals; isolation methods