title: Effects of using retention-pond water for dust abatement on performance of feedlot steers and carriage of Escherichia coli O157 and Salmonella spp.
abstract: OBJECTIVE
  To evaluate the effects of using retention-pond water for dust abatement on performance of feedlot steers and carriage of Escherichia coli O157 and Salmonella spp.
  
  
  METHODS
  Matched cohort studies.
  
  
  METHODS
  2 groups of feedlot steers comprising 3,510 (pathogen carriage) and 3,737 (performance) animals housed in a large commercial feedlot in the Texas Panhandle.
  
  
  METHODS
  Steers were systematically allocated to treatment pens approximately 60 days after arrival (pathogen carriage) or at arrival (performance). For evaluation of pathogen carriage, feces and hide swab specimens were collected from 25 animals in each pen within 10 days of slaughter. Samples were submitted for bacterial culture for E. coli O157 and were tested with a polymerase chain reaction-based assay for Salmonella spp. For evaluation of performance, pen weights of animals were obtained at arrival and slaughter and feed delivered to each pen was recorded. The exposure of interest for both studies was application of retention-pond water through fixed high-pressure sprinklers.
  
  
  RESULTS
  Carriage of E. coli O157 and Salmonella spp and animal performance were not adversely affected by exposure to retention-pond water. Prevalences of E. coli O157 in feces, on hides, and either in feces or on hides for those exposed to retention-pond water were 8.3%, 8.9%, and 15.4%, respectively; prevalences for those unexposed to retention-pond water were 11.4%, 15.4%, and 22.6%, respectively.
  
  
  CONCLUSIONS
  Results suggest that use of retention-pond water for dust abatement in feedlot pens does not adversely affect pathogen carriage or animal performance.
authors.affiliation: Feedlot Research Group, Division of Agriculture, College of Agriculture, Nursing, Natural Sciences, and Engineering, West Texas A&M University, Canyon, TX 79016, USA.
authors.forename: Guy H
authors.initials: GH
authors.lastname: Loneragan
authors.forename: Mindy M
authors.initials: MM
authors.lastname: Brashears
mesh_terms: D000818:Animals; D002353:Carrier State / Q000517:prevention & control / Q000662:veterinary*; D002417:Cattle / Q000254:growth & development* / Q000382:microbiology; D002418:Cattle Diseases / Q000517:prevention & control; D015331:Cohort Studies; D015169:Colony Count, Microbial / Q000662:veterinary; D004391:Dust / Q000517:prevention & control*; D004927:Escherichia coli Infections / Q000517:prevention & control / Q000662:veterinary; D019453:Escherichia coli O157 / Q000254:growth & development / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D008297:Male; D011897:Random Allocation; D012475:Salmonella / Q000254:growth & development / Q000302:isolation & purification*; D012481:Salmonella Infections, Animal / Q000517:prevention & control; D012867:Skin / Q000382:microbiology; D013781:Texas; D014867:Water; D015430:Weight Gain
chemical_list: D004391:Dust; D014867:Water