Logo image
Back
Antimicrobial susceptibility, plasmid replicon typing, phylogenetic grouping, and virulence potential of avian pathogenic and faecal Escherichia coli isolated from meat chickens in Australia
Journal article   Peer reviewed

Antimicrobial susceptibility, plasmid replicon typing, phylogenetic grouping, and virulence potential of avian pathogenic and faecal Escherichia coli isolated from meat chickens in Australia

L. Awawdeh, C. Turni, J. L. Mollinger, J. Henning, R. N. Cobbold, D. J. Trott and J. S. Gibson
Avian pathology, Vol.51(4), pp.349-360
04/07/2022
DOI: https://doi.org/10.1080/03079457.2022.2065969
PMID: 35417283

Metrics

1 Record Views
8 Times Cited - Web of Science

Abstract

Avian colibacillosis antimicrobial resistance avian pathogenic Escherichia coli extended-spectrum cephalosporins fluoroquinolones phylogenetic groups plasmid replicon virulence gene
Globally, avian colibacillosis is a leading cause of morbidity and mortality in poultry, associated with economic losses and welfare problems. Here, clinical avian pathogenic E. coli isolates (CEC; n = 50) and faecal E. coli isolates from healthy (FEC; n = 187) Australian meat chickens collected between 2006 and 2014 were subjected to antimicrobial susceptibility testing, phylogenetic grouping, plasmid replicon (PR) typing, multilocus sequence typing, and virulence gene (VG) profiling. Extended-spectrum cephalosporin (ESC)- and fluoroquinolone (FQ)-resistant E. coli isolates underwent further genetic characterization. Significant proportions of CEC and FEC were, respectively, susceptible (13/50; 48/187) or MDR (9/50; 26/187) to 20 tested antimicrobials. Phylogenetic groups A and C, and PR types IncFIB and IncFrep were most represented. Five tested CEC-associated VGs were more prevalent in CEC (>= 90%) than FEC (<= 58%). Some isolates (CEC n = 3; FEC n = 7) were resistant to ESCs and/or FQs and possessed signature mutations in chromosomal FQ target genes and plasmid-mediated qnrS, bla(CMY-2), and bla(DHA-1) genes. Sequence type 354 (n = 4), associated with extraintestinal infections in a broad range of hosts, was prevalent among ESC- and/or FQ-resistant FEC. This study confirmed existence of a small reservoir of ESC- and FQ-resistant E. coli in Australian commercial meat chickens despite absence of use in the industry of these drugs. Otherwise, diversity of VGs and PR types in both FEC and CEC populations was identified. We hypothesize that the source of ESC- and FQ-resistant E. coli is external to poultry production facilities.

Details

Logo image