Factors associated with fecal shedding of verotoxin-producing Escherichia coli O157 on dairy farms.
Fecal samples were collected from 4,361 dairy cows on 91 dairy operations between 26 February and 8 July 1996. Fecal samples were cultured for Escherichia coli O157, and positive isolates were probed for verotoxin-producing genes. A total of 52 (1.2%) fecal samples on 22 (24.2%) operations were positive for verotoxin-producing E. coli O157. Herds in which samples were collected on or after 1 May 1996 were significantly more likely to test positive than herds sampled before that date (odds ratio = 7.7). Herds maintained on farms on which alleyways were flushed with water to remove manure were 8.0 times more likely to have samples test positive for verotoxin-producing E. coli O157 than were herds maintained on farms cleaned by use of other methods of manure removal.
U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Centers for Epidemiology and Animal Health, Fort Collins, Colorado 80521, USA. lindsey.p.garber@usda.gov
L
L
Garber
S
S
Wells
L
L
Schroeder-Tucker
K
K
Ferris
D000821:Animal Feed; D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis*; D002417:Cattle / Q000382:microbiology*; D003612:Dairying; D019453:Escherichia coli O157 / Q000302:isolation & purification* / Q000378:metabolism; D005243:Feces / Q000382:microbiology*; D012307:Risk Factors; D022622:Shiga Toxin 1
D001427:Bacterial Toxins; D022622:Shiga Toxin 1