title: Occurrence and characterization of Escherichia coli O157 isolated from cattle in Norway.
abstract: Faecal samples from 504 imported beef cattle were screened to investigate the occurrence of Escherichia coli O157. The results were compared with those from a previous screening of Norwegian dairy cattle, and the occurrence was found to be higher in the imported beef cattle. The E. coli O157 isolates from the previous and present studies were characterized for the genes encoding for shigatoxin 1 (stx1), shigatoxin 2 (stx2), the intimin protein (eae) and the flagellar protein H7 (fliC) using PCR analysis, pulsed-field gel electrophoresis (PFGE) with the restriction enzyme XbaI, and bacteriophage lambda RFLP analysis using the PvuII restriction enzyme. The isolates from the dairy and beef cattle could be distinguished by the profiles of the toxin genes and by PFGE patterns. Whether the importation of animals in itself should be regarded as a risk factor for the occurrence of E. coli O157, or whether other management factors contribute to the differences in carrier rates compared to the previous study on domestic cattle, is discussed.
authors.affiliation: Department of Pharmacology, Microbiology and Food Hygiene, The Norwegian School of Veterinary Science, Oslo. line.vold@veths.no
authors.forename: L
authors.initials: L
authors.lastname: Vold
authors.forename: M
authors.initials: M
authors.lastname: Sandberg
authors.forename: J
authors.initials: J
authors.lastname: Jarp
authors.forename: Y
authors.initials: Y
authors.lastname: Wasteson
mesh_terms: D018829:Adhesins, Bacterial; D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000907:Antibodies, Bacterial / Q000737:chemistry; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics; D015139:Blotting, Southern / Q000662:veterinary; D002352:Carrier Proteins; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification; D015252:Deoxyribonucleases, Type II Site-Specific / Q000737:chemistry; D016521:Electrophoresis, Gel, Pulsed-Field / Q000662:veterinary; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000662:veterinary*; D019453:Escherichia coli O157 / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D029968:Escherichia coli Proteins; D005243:Feces / Q000382:microbiology; D005260:Female; D005408:Flagellin / Q000737:chemistry / Q000235:genetics; D018189:Immunomagnetic Separation / Q000662:veterinary; D009664:Norway / Q000453:epidemiology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012150:Polymorphism, Restriction Fragment Length; D022622:Shiga Toxin 1 / Q000737:chemistry / Q000235:genetics; D022641:Shiga Toxin 2 / Q000737:chemistry / Q000235:genetics
chemical_list: D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; D005408:Flagellin; C073819:eaeA protein, E coli; C025580:endodeoxyribonuclease XBAI; C025630:CAGCTG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific