title: Clonal diversity of ESBL-producing Escherichia coli in pigs at slaughter level in Portugal.
abstract: We aimed to determine the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in fecal samples of healthy pigs, and to evaluate their clonality and associated resistance. Forty-nine percent of pigs sampled (n=35/71) in a slaughterhouse in Portugal revealed ESBL-producing E. coli isolates. Most isolates produced CTX-M-1 enzyme (71.4%; n=25/35), followed by CTX-M-9 (11.4%; n=4/35), CTX-M-14 (5.7%; n=2/35), SHV-12 (5.7%; n=2/35), and CTX-M-32 (5.7%; n=2/35). Ninety-four percent of the isolates presented a phenotype of multi-resistance. Most isolates belonged to phylogroups B1 (42.8%; n=15/35) and A (40%; n=14/35). Multilocus sequence typing (MLST) analysis revealed nine sequence types (STs) under six clonal complexes (CCs) and nine singletons, including overrepresentation of CC10 and three new STs (ST2524, ST2525, ST2528). We observed the frequent presence of CTX-M-producing E. coli in pigs at slaughter level, most of them belonging to CC10, commonly recovered from clinical samples.
authors.affiliation: Centre of Studies of Animal and Veterinary Sciences, Vila Real, Portugal.
authors.forename: Sónia
authors.initials: S
authors.lastname: Ramos
authors.forename: Nuno
authors.initials: N
authors.lastname: Silva
authors.forename: Daniela
authors.initials: D
authors.lastname: Dias
authors.forename: Margarida
authors.initials: M
authors.lastname: Sousa
authors.forename: José Luis
authors.initials: JL
authors.lastname: Capelo-Martinez
authors.forename: Francisco
authors.initials: F
authors.lastname: Brito
authors.forename: Manuela
authors.initials: M
authors.lastname: Caniça
authors.forename: Gilberto
authors.initials: G
authors.lastname: Igrejas
authors.forename: Patrícia
authors.initials: P
authors.lastname: Poeta
mesh_terms: D000003:Abattoirs; D000818:Animals; D015373:Bacterial Typing Techniques; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary*; D004197:Disease Reservoirs / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D014644:Genetic Variation / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D010641:Phenotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011174:Portugal; D015995:Prevalence; D017422:Sequence Analysis, DNA; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D001618:beta-Lactamases