title: Phylogenetic background and virulence genes of Escherichia coli isolates from colisepticemic and healthy broiler chickens in Iran.
abstract: The purposes of this study were to determine the phylogenetic background and the virulence gene profiles of Escherichia coli isolates from colisepticemic and feces of healthy (AFEC) broiler chickens. In this study, 253 E. coli isolates including 141 avian pathogenic E. coli (APEC) and 112 AFEC isolates were examined by PCR. In general, 253 E. coli isolates distributed among group A (51.8%), B1 (15.8%), B2 (8.7%), and D (23.7%). Ten (8.9%) AFEC isolates segregated in to B1 phylo-group and 102 (91.1%) isolates fell into six different phylogenetic subgroups. Distribution of colisepticemic and fecal isolates differed significantly in their assignments to A and B1 phylo-groups. The three most prevalent virulence genes were crl, fimH, and aer in isolates between both groups. The four genetic markers aer, papC, afa, and sfa were detected significantly more often among colisepticemic isolates than in fecal isolates from healthy broilers. The presence of stx ( 2 ) gene in fecal isolates were significantly differs among the colisepticemic isolates. F17 fimbrial family encoding gene and eae gene were detected in APEC and AFEC isolates, respectively. The colisepticemic and fecal isolates possessed the virulence genes were detected in all of the four phylogenetic groups. Several combination patterns of the virulence genes were detected in APEC and AFEC isolates. In colisepticemic isolates the combination of aer, crl, and fimH genes was the most prevalent pattern. None of the examined isolates harbored the cdt, cnf1, ipaH, and stx ( 1 ) virulence gene sequences.
authors.affiliation: Molecular Microbiology Research Group, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, P.O. Box 7616914111, Kerman, Iran. ghanbar@mail.uk.ac.ir
authors.forename: Reza
authors.initials: R
authors.lastname: Ghanbarpour
authors.forename: Masoud
authors.initials: M
authors.lastname: Sami
authors.forename: Mahmood
authors.initials: M
authors.lastname: Salehi
authors.forename: Mahla
authors.initials: M
authors.lastname: Ouromiei
mesh_terms: D000818:Animals; D002645:Chickens; D004926:Escherichia coli / Q000235:genetics* / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000235:genetics / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005819:Genetic Markers / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011201:Poultry Diseases / Q000382:microbiology*; D018805:Sepsis / Q000382:microbiology*; D014774:Virulence
chemical_list: D005819:Genetic Markers