title: Escherichia coli O157:H7 excretion by commercial feedlot cattle fed either barley- or corn-based finishing diets.
abstract: Effective preharvest control measures for Escherichia coli O157:H7 in cattle may significantly reduce the incidence of human disease caused by this organism. The prevalence and magnitude of fecal E. coli O157:H7 excretion was evaluated in 15 pens (300 to 500 cattle per pen) of commercial feedlot cattle fed a barley-based finishing ration and compared with that in 15 pens of cattle fed a corn-based ration. Average E. coli O157:H7 prevalence was 2.4% in barley-fed cattle and 1.3% in the corn-fed cattle (P < 0.05), and average magnitude of fecal E. coli O157:H7 excretion was 3.3 log CFU/g in the barley-fed cattle and 3.0 log CFU/g in the corn-fed cattle (P < 0.01). Corn-fed cattle had lower average fecal pH values (5.85) than did barley-fed cattle (6.51) (P < 0.01), and the average total generic fecal E. coli concentration in this group of animals (6.24 log CFU/g) was greater than that in the barley-fed cattle (5.55 log CFU/g) (P < 0.01). Specific feed ingredients may impact the frequency and magnitude of fecal excretion of E. coli O157:H7 by cattle.
authors.affiliation: Lakeside Research, Lakeside Feeders, Ltd., P.O. Box 800, Brooks, Alberta, Canada T1R 1B7.
authors.forename: Janice
authors.initials: J
authors.lastname: Berg
authors.forename: Tim
authors.initials: T
authors.lastname: McAllister
authors.forename: Susan
authors.initials: S
authors.lastname: Bach
authors.forename: Robert
authors.initials: R
authors.lastname: Stilborn
authors.forename: Dale
authors.initials: D
authors.lastname: Hancock
authors.forename: Jeffrey
authors.initials: J
authors.lastname: LeJeune
mesh_terms: D000821:Animal Feed; D000818:Animals; D002417:Cattle / Q000382:microbiology*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005243:Feces / Q000737:chemistry / Q000382:microbiology*; D001467:Hordeum; D006863:Hydrogen-Ion Concentration; D003313:Zea mays