Isolation of shiga-toxigenic Escherichia coli O157 from hide surfaces and the oral cavity of finished beef feedlot cattle

Abstract
Objective—To determine whether viable shiga-toxigenic Escherichia coli (STEC) O157 could be isolated from hide surface locations and the oral cavity of finished beef feedlot cattle. Design—Within-animal prevalence distribution survey. Animals—139 finished cattle in 4 pens in a feedlot in Nebraska; prevalence of fecal STEC O157 shedding ranged from 20 to > 90%. Procedure—Samples were collected from 7 sites from each animal: feces, oral cavity, and 5 hide surface locations (lumbar region, ventral aspect of the neck, ventral abdominal midline [ventrum], dorsal thoracic midline [back], and distal aspect of the left hind limb [hock]). Results—Viable STEC O157 were isolated from the oral cavity or 1 or more hide surfaces of 130 cattle, including 50 fecal isolation-negative cattle. Site-specific prevalence of STEC O157 was 74.8% for oral cavity samples, 73.4% for back samples, 62.6% for neck samples, 60.4% for fecal samples, 54.0% for flank samples, 51.1% for ventrum samples, and 41.0% for hock samples. Only 5 c...