Genotypic and phenotypic diversity differences of presumptive commensal and avian pathogenic E. coli

ABSTRACT

1. The objective of the experiment was to characterise the genotypic and phenotypic differences between presumptive commensal E. coli and avian pathogenic E. coli (APEC) of poultry.

2. DNA was extracted from 65 confirmed APEC E. coli from chicken, 100 presumptive commensal E. coli from healthy turkey and 35 from healthy chicken. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and virulence factors genotyping was performed to characterise genetic features.

3. Carbon source utilisation and antimicrobial susceptibility tests were performed to characterise phenotypic features of isolates.

4. The genetic divergence between E. coli strains tested by ERIC-PCR profiles and virulence-associated genes showed a clear genetic separation between E. coli APEC and turkey E. coli strains.

5. The carbon utilisation profile of turkey isolates was different from chicken and APEC strains; whereas antimicrobial susceptibility was highest for turkey isolates (53%), and lowest for APEC strains (33.8%).

6. The study showed a significant negative correlation between utilisation of arabitol and adonitol with different virulence determinants tested, which suggests that the ability to utilise some uncommon carbon sources may be used to discriminate between presumptive commensal E. coli and APEC.

KEYWORDS:

• Antimicrobial resistance
• APEC
• carbon source
• commensal
• E. coli
• virulence genes

Acknowledgments

We acknowledge the gift of strains from the Veterinary School and of the University of Surrey (Roberto La Ragione) and colleagues at CEDAR and the Department of Agriculture (Caroline Rymer and Darren Junper) for access to chicken and poultry studies for the isolation of E. coli.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplementary material can be accessed here.

Additional information

Funding

This work was supported by the Kuwait Government – Public Authority of Agriculture and Fish Resources.