Virulence genotyping of Escherichia coli isolates from avian cellulitis in relation to phylogeny

Coliform cellulitis in broilers is caused by certain avian pathogenic Escherichia coli strains. Sixty-four E. coli samples were isolated in a slaughterhouse from broiler carcasses with cellulitis. The isolates were examined for the presence of selected virulence genes and phylogenetic determination by PCR assays. E. coli isolates belonged to A (51.56%), B1 (18.75%) and D (29.68%) phylogenetic groups. All of the isolates were positive for at least two virulence genes. The three most prevalent genes were csgA (92.18%), fimH (85.93%) and iucD (76.56%). F17 fimbrial family (f17A), P (papC) and S (sfa) fimbriae encoding genes were detected in one, nine and two isolates, respectively. The highest and the lowest number of virulence genes were found in D and A phylogenetic groups, respectively. Several combination of the virulence genes were detected; csgA, fimH, iucD was the most prevalent pattern. None of the isolates harboured the afa E-VIII, afaI B-C, eaeA, hly, stx1 and stx virulence genes. © Springer-Verlag London Limited 2009.