Virulence genes in isolates of Escherichia coli from samples of milk and feces from dairy cattle

J Food Prot. 2012 Sep;75(9):1698-700. doi: 10.4315/0362-028X.JFP-11-468.

Abstract

The aim of this work was to determine if Escherichia coli isolates carrying the virulence genes eae and eltB and exhibiting the Ehly phenotype are present in feces and milk samples from healthy dairy cattle on farms. Isolates from calves showed a statistically higher prevalence of eae and eltB compared with isolates from older animals. The other factors tested (stx(1), stx(2), and Ehly) were not statistically different between the two groups. Two isolates originating from calf feces were identified as serotype O157:H7; one of these isolates carried stx(1) and eae, the other stx(2) and eae. E. coli isolated from milk contained stx(1), stx(2), and eltB. The results show that feces or milk from healthy dairy cattle may contain E. coli pathotypes that express virulence genes, indicating that these materials have zoonotic potential. The results also reinforce the idea that host age can influence the dynamics of virulence genes in E. coli from cattle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Animals
  • Animals, Newborn
  • Cattle / microbiology
  • Disease Reservoirs / microbiology
  • Disease Reservoirs / veterinary*
  • Escherichia coli / isolation & purification
  • Escherichia coli / pathogenicity*
  • Feces / microbiology*
  • Food Microbiology
  • Humans
  • Milk / microbiology*
  • Prevalence
  • Virulence Factors / genetics*

Substances

  • Virulence Factors