Virulence factors and antibiotic resistance of avian pathogenic Escherichia coli in eastern China

Introduction: Avian pathogenic Escherichia coli (APEC) causes serious colibacillosis and significant economic losses. Data on profiles of virulence factors and antibiotic resistances among APEC strains are crucial to the control of infection. In this study, strains were isolated from eastern China, and the prevalence of virulence factors and distribution of antibiotic resistance were determined. Material and Methods: APEC strains were isolated and characterised by PCR for O serogroups, virulence factor genes, antibiotic resistance, and phylogenetic groups. Results: O78 was the most prevalent serogroup and type A was the most frequent phylogenetic group. The fimH, feoB, and iron genes were the most prevalent among the isolates. All isolates were multiresistant, and all strains were resistant to ampicillin and tetracycline, which are widely used in the poultry industry in China. Conclusion: This study provided important data on the presence of virulence genes and antibiotic resistance profiles of APEC from poultry farms in eastern China.