title: Duration of detection of fecal excretion of Escherichia coli O157:H7 in cattle.
abstract: To better define the bovine reservoir of Escherichia coli O157:H7, cattle were tested monthly by bacteriologic culture for fecal excretion of E. coli. E. coli O157:H7 was isolated from feces of 56 cattle sampled an average of 6.98 times (2-12 samples). By broth enrichment culture, immunomagnetic separation, or both, 35 cattle had 1 positive sample, 12 had 2, 7 had 3, and 1 each had 4 and 5. Five cattle with > or = 2 positive samples were in a herd in which 5 pulsed-field gel electrophoretic (PFGE) types were simultaneously present; in 3 of these cattle, different PFGE types were detected in different samples. The duration of detected excretion E. coli O157:H7 by individual cattle in this study was <1 month in 35 (63%) of 56 cattle. Both serial and concurrent excretion of different E. coli O157:H7 strains by individual cattle was observed.
authors.affiliation: Department of Veterinary Microbiology and Pathology, Washington State University, Pullman 99165-7040, USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Besser
authors.forename: D D
authors.initials: DD
authors.lastname: Hancock
authors.forename: L C
authors.initials: LC
authors.lastname: Pritchett
authors.forename: E M
authors.initials: EM
authors.lastname: McRae
authors.forename: D H
authors.initials: DH
authors.lastname: Rice
authors.forename: P I
authors.initials: PI
authors.lastname: Tarr
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004927:Escherichia coli Infections / Q000382:microbiology*; D019453:Escherichia coli O157 / Q000472:pathogenicity*; D005243:Feces / Q000382:microbiology; D015183:Restriction Mapping; D013997:Time Factors
chemical_list: D004269:DNA, Bacterial