title: Increasing prevalence of Campylobacter jejuni in feedlot cattle through the feeding period.
abstract: The prevalence of Campylobacter jejuni in commercial feedlot cattle was monitored throughout the feeding period by repeated bacteriologic culture of feces. Fecal pats (n = 10) in 20 feedlot pens were sampled at 2-weeks interval beginning at entry into the feedlot and continuing until slaughter. The least-squares mean C. jejuni prevalence increased from 1.6% at the first sampling to 61.3% at the final sampling just prior to slaughter. Diverse C. jejuni pulsed-field gel electrophoresis macrorestriction profiles (MRP) were identified among the cattle isolates, but five prevalent MRP and minor variants accounted for >80% of all typed isolates. Chlorination of the water supplied to the water troughs of half of the pens did not affect C. jejuni prevalence in the cattle. Overall, the least-squares mean C. jejuni prevalences were 45.6 and 43.6% in chlorinated and nonchlorinated feedlot pens, respectively. The results of this study demonstrate apparent transmission of C. jejuni among feedlot cattle during the feeding period, unaffected by water chlorination, resulting in a high prevalence of C. jejuni excretion by cattle approaching slaughter.
authors.affiliation: Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA. tbesser@vetmed.wsu.edu
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Besser
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Lejeune
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Rice
authors.forename: Janice
authors.initials: J
authors.lastname: Berg
authors.forename: R P
authors.initials: RP
authors.lastname: Stilborn
authors.forename: Katherine
authors.initials: K
authors.lastname: Kaya
authors.forename: Wonki
authors.initials: W
authors.lastname: Bae
authors.forename: Dale D
authors.initials: DD
authors.lastname: Hancock
mesh_terms: D000821:Animal Feed / Q000382:microbiology*; D000822:Animal Husbandry / Q000379:methods; D000818:Animals; D002169:Campylobacter Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D016123:Campylobacter jejuni / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D002713:Chlorine / Q000008:administration & dosage; D004203:Disinfection / Q000379:methods; D005243:Feces / Q000382:microbiology*; D005618:Fresh Water / Q000737:chemistry / Q000382:microbiology; D015995:Prevalence; D014881:Water Supply
chemical_list: D002713:Chlorine