| Summary: | Continuous monitoring of antimicrobial resistance in bacteria along the food chain is crucial for the assessment of human health risks. Uncritical use of antibiotics in farming over years can be one of the main reasons for increased antibiotic resistance in bacteria. In this study, we aimed to classify 222 presumptive <i>Pseudomonas</i> isolates originating from a salmon processing environment, and to examine the phenotypic and genotypic antibiotic resistance profiles of these isolates. Of all the analyzed isolates 68% belonged to <i>Pseudomonas</i>, and the most abundant species were <i>Pseudomonas fluorescens</i>, <i>Pseudomonas azotoformans</i>, <i>Pseudomonas gessardii</i>, <i>Pseudomonas libanesis</i>, <i>Pseudomonas lundensis</i>, <i>Pseudomonas cedrina</i> and <i>Pseudomonas extremaustralis</i> based on sequencing of the <i>rpoD</i> gene. As many as 27% of <i>Pseudomonas</i> isolates could not be classified to species level. Phenotypic susceptibility analysis by disc diffusion method revealed a high level of resistance towards the antibiotics ampicillin, amoxicillin, cefotaxime, ceftriaxone, imipenem, and the fish farming relevant antibiotics florfenicol and oxolinic acid among the <i>Pseudomonas</i> isolates. Whole genome sequencing and subsequent analysis of AMR determinants by ResFinder and CARD revealed that no isolates harbored any acquired resistance determinants, but all isolates carried variants of genes known from <i>P. aeruginosa</i> to be involved in multidrug efflux pump systems.
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