title: Antimicrobial resistance and molecular characterization of virulence genes, phylogenetic groups of Escherichia coli isolated from diarrheic and healthy camel-calves in Tunisia.
abstract: This study was conducted to determine the prevalence of virulence genes, serogroups, antimicrobial resistance and phylogenetic groups of Escherichia coli strains isolated from diarrheic and healthy camel calves in Tunisia. From 120 fecal samples (62 healthy and 58 diarrheic camel calves aged less than 3 months), 70 E. coli isolates (53 from diarrheic herds and 17 from healthy herds) were examined by PCR for detection of the virulence genes associated with pathogenic E. coli in animals. A significantly greater frequency of the f17 gene was observed in individual camels and in herds with diarrhea, this gene being found in 44.7% and 41.5% of isolates from camels and herds with diarrhea versus 22.5% and 11.7% in camels (p=0.05) and herds without diarrhea (p=0.02). The aida, cnf1/2, f18, stx2 and paa genes were found only in isolates from camels with diarrhea, although at a low prevalence, 1.8%, 3.7%, 1.8%, 3.7% and 11.3%, respectively. Prevalence of afa8, cdtB, eae, east1, iroN, iss, kpsMTII, paa, sfa, tsh and papC genes did not differ significantly between herds with or without diarrhea. Genes coding for faeG, fanC, f41, estI, estII, CS31a and eltA were not detected in any isolates. All isolates were sensitive to amikacin, chloramphenicol, ciprofloxacin, gentamicin and ceftiofur and the highest frequency of resistance was observed to tetracycline, and ampicillin (52.8% and 37.1% respectively). The phylogenetic groups were identified by conventional triplex PCR. Results showed that E. coli strains segregated mainly in phylogenetic group B1, 52.8% in diarrheic herds and 52.9% in healthy herds.
authors.affiliation: Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabès, Médenine, Tunisia; Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia. Electronic address: bessalahsalma@yahoo.fr.
authors.forename: Salma
authors.initials: S
authors.lastname: Bessalah
authors.affiliation: OIE Reference Laboratory for Escherichia coli (EcL), Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC, Canada.
authors.forename: John Morris
authors.initials: JM
authors.lastname: Fairbrother
authors.affiliation: Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabès, Médenine, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Salhi
authors.affiliation: OIE Reference Laboratory for Escherichia coli (EcL), Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC, Canada.
authors.forename: Ghyslaine
authors.initials: G
authors.lastname: Vanier
authors.affiliation: Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabès, Médenine, Tunisia.
authors.forename: Touhami
authors.initials: T
authors.lastname: Khorchani
authors.affiliation: Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabès, Médenine, Tunisia.
authors.forename: Mouldi Mabrouk
authors.initials: MM
authors.lastname: Seddik
authors.affiliation: Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabès, Médenine, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hammadi
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002162:Camelus / Q000382:microbiology*; D002939:Ciprofloxacin / Q000494:pharmacology; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology* / Q000662:veterinary; D029968:Escherichia coli Proteins / Q000235:genetics; D005243:Feces / Q000382:microbiology; D005838:Genotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013752:Tetracycline / Q000494:pharmacology; D014416:Tunisia / Q000453:epidemiology; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D037521:Virulence Factors; D002939:Ciprofloxacin; D013752:Tetracycline
keywords: Antimicrobial resistance; Camels; Diarrhea; Escherichia coli; Virulence factor