Wild Duck (Anas platyrhynchos) as a Source of Antibiotic-Resistant Salmonella enterica subsp. diarizonae O58-The First Report in Poland

Abstract

The "One Health" approach increasingly demonstrates the global spread of pathogenic microorganisms and their antimicrobial resistance in the environment, both in animals and humans. Salmonella enterica subsp. diarizonae is nowadays very often isolated from cold-blooded reptiles to a lesser extent from sheep, but unfortunately more and more often from humans. However, there are a few studies describing the isolation of Salmonella enterica subsp. diarizonae from migratory wild birds. The mallard duck (Anas platyrhynchos), a wild animal that traverses the continent of Eurasia, can be an excellent indicator of the spread of intestinal microbes as well as their resistance to antibiotics. This is the first report of the Salmonella enterica subsp. diarizonae detection in Poland in a migrating mallard duck. This research presented the identification difficulties associated with the isolation of Salmonella enterica subsp. diarizonae using three different biochemical tests and advanced serology tests. At the same time, we detected very high antimicrobial resistance in the isolated strain. By using the minimum inhibitory concentration (MIC) method, it was found that the isolated strain of S. enterica subsp. diarizonae has high antibiotic resistance against 14 of the 33 tested antimicrobials agents. The resistance genes that have been identified in S. enterica subsp. diarizonae include aadA, strA/strB, and bla_TEM.

Keywords: Salmonella enterica subsp. diarizonae; antibiotic-resistant Salmonella; wild duck.

Figure 1

Agarose gel (2%) electrophoresis showing the amplification of multiplex PCR line 1 strA/strB (893 bp) and aadA (525 bp), multiplex PCR line 2 bla_TEM (247 bp) of Salmonella enterica subsp. diarizonae O58. Notes: line M DNA marker, line K1+ bla_TEM (247 bp), and line K2+ positive control genes sul2 (721 bp), aadA (525 bp), as positive controls were Klebsiella pneumoniae and E. coli strains isolated from poultry and cattle. Lane K—no template (negative control). Abbreviations: M—DNA marker (DNA Marker 2+, (50–1000 bp, A&A Biotechnology Gdańsk, Poland); bp—base pairs.