The material consisted of 60 putative ESBL/AmpC-producing Escherichia coli (n=58) and Klebsiella pneumoniae (n=2) isolates that were selected from the strain collection of the Finnish Food Authority. Isolates were derived from 48 dogs originating from seven countries in 2017-2018. Most of the dogs had a shelter background. Phenotypic resistance was investigated by selective isolation and antibiotic susceptibility testing. Subsequently the isolates were subjected to whole genome sequencing to study the genomic characteristics of the selected isolates. Bioinformatic analyses revealed a high diversity of different antimicrobial resistance genes (n=56) and sequence types (n=32), including high-risk clonal lineages Escherichia coli ST410 (n=3) and Klebsiella pneumoniae ST307. Genes encoding resistance to β-lactams accounted for the majority, with the most frequent gene being blaCTX-M-15, which has recently been reported as the predominant β-lactamase gene amongst companion animals globally. Of the 58 ESBL/AmpC-producing Eschericia coli isolates 29% were qualified as presumptive ExPEC and/or uropathogenic Eschericia coli, most of which belonged to B2 phylogroup that is commonly associated with urinary tract infections in humans and dogs. The results highlight the multiplicity of genetic backgrounds disseminating ESBL/AmpC-genes in the studied dogs, calling for further investigation of possible drivers responsible for the dissemination of antimicrobial resistance genes in animal shelters and amongst stray dogs.
This study was conducted in collaboration with the Finnish Food Authority. This work was supported by The Päivikki and Sakari Sohlberg Foundation.
The published peer-reviewed article can be found at: https://doi.org/10.1016/j.jgar.2022.05.021