title: Distribution of Escherichia coli strains harbouring Shiga toxin-producing E. coli (STEC)-associated virulence factors (stx1, stx2, eae, ehxA) from very young calves in the North Island of New Zealand.
abstract: The objective of this study was to determine the distribution of Shiga toxin-producing Escherichia coli (STEC) virulence markers (stx1, stx2, eae, ehxA) in E. coli strains isolated from young calves aged fewer than 7 days (bobby calves). In total, 299 recto-anal mucosal swabs were collected from animals at two slaughter plants and inoculated onto tryptone bile X-glucuronide and sorbitol MacConkey agar supplemented with cefixime and potassium tellurite. Isolates were analysed using multiplex polymerase chain reaction to detect stx1, stx2, eae and ehxA genes. The most common combination of virulence markers were eae, ehxA (n = 35) followed by eae (n = 9). In total, STEC and atypical enteropathogenic E. coli (aEPEC) were isolated from 8/299 (2·6%) and 37/299 (12·3%) calves, respectively. All the isolates could be assigned to 15 genotype clusters with >70% similarity cut-off using XbaI pulsed-field gel electrophoresis. It may be concluded that healthy calves from the dairy industry are asymptomatic carriers of a diverse population of STEC and aEPEC in New Zealand.
authors: mEpiLab, Hopkirk ResearchInstitute,Massey University,Palmerston North,New Zealand.
authors: H
authors: H
authors: Irshad
authors: AgResearch Ltd, Grasslands Research Centre, Palmerston North,New Zealand.
authors: A L
authors: AL
authors: Cookson
authors: mEpiLab, Hopkirk ResearchInstitute,Massey University,Palmerston North,New Zealand.
authors: D J
authors: DJ
authors: Prattley
authors: Enteric Reference Laboratory, ESR-NCBID,New Zealand.
authors: M
authors: M
authors: Dufour
authors: mEpiLab, Hopkirk ResearchInstitute,Massey University,Palmerston North,New Zealand.
authors: N P
authors: NP
authors: French
mesh_terms: D000003:Abattoirs; D018829:Adhesins, Bacterial / Q000235:genetics; D000818:Animals; D000831:Animals, Newborn; D002417:Cattle / Q000382:microbiology*; D002418:Cattle Diseases / Q000453:epidemiology / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000235:genetics; D006460:Hemolysin Proteins / Q000235:genetics; D009520:New Zealand / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D022622:Shiga Toxin 1 / Q000235:genetics; D022641:Shiga Toxin 2 / Q000235:genetics; D054323:Shiga-Toxigenic Escherichia coli / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics*
chemical_list: D018829:Adhesins, Bacterial; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; C073819:eaeA protein, E coli