title: Agreement Among 4 Sampling Methods to Identify Respiratory Pathogens in Dairy Calves with Acute Bovine Respiratory Disease.
abstract: BACKGROUND
  Four sampling techniques commonly are used for antemortem identification of pathogens from cattle with bovine respiratory disease (BRD): the nasal swab (NS), guarded nasopharyngeal swab (NPS), bronchoalveolar lavage (BAL), and transtracheal wash (TTW). Agreement among these methods has not been well characterized.
  
  
  OBJECTIVE
  To evaluate agreement among TTW and NS, NPS, or BAL for identification of viral and bacterial pathogens in dairy calves with BRD.
  
  
  METHODS
  One hundred dairy calves with naturally acquired BRD.
  
  
  METHODS
  Calves were sampled by all 4 methods. Viral agents were identified by real-time RT-PCR, bacteria were identified by aerobic culture, and Mycoplasma bovis (M. bovis) isolates were speciated by PCR. Agreement among TTW and NS, NPS, or BAL was evaluated by calculating the kappa statistic and percent positive agreement. McNemar's exact test was used to compare the proportions of positive results.
  
  
  RESULTS
  Agreement among TTW and NS, TTW and NPS, and TTW and BAL, was very good for identification of P. multocida, M. haemolytica, and M. bovis. For bovine respiratory syncytial virus (BRSV), agreement with TTW was moderate for NS, good for NPS, and very good for BAL. For bovine coronavirus (BCV), agreement with TTW was moderate for NS and NPS, and good for BAL. McNemar's test was significant only for BCV, indicating that for this pathogen the proportion of positive results from NS and NPS could not be considered comparable to TTW.
  
  
  CONCLUSIONS
  This study provides guidance for veterinarians selecting diagnostic tests for antemortem identification of pathogens associated with BRD.
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: D
authors.initials: D
authors.lastname: Doyle
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: B
authors.initials: B
authors.lastname: Credille
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare, CA.|Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, Tulare, CA.
authors.forename: T W
authors.initials: TW
authors.lastname: Lehenbauer
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: R
authors.initials: R
authors.lastname: Berghaus
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare, CA.|Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, Tulare, CA.
authors.forename: S S
authors.initials: SS
authors.lastname: Aly
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare, CA.
authors.forename: J
authors.initials: J
authors.lastname: Champagne
authors.affiliation: California Animal Health & Food Safety Laboratory System, University of California, Davis, CA.
authors.forename: P
authors.initials: P
authors.lastname: Blanchard
authors.affiliation: California Animal Health & Food Safety Laboratory System, University of California, Davis, CA.
authors.forename: B
authors.initials: B
authors.lastname: Crossley
authors.affiliation: Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: L
authors.initials: L
authors.lastname: Berghaus
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: S
authors.initials: S
authors.lastname: Cochran
authors.affiliation: Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA.
authors.forename: A
authors.identifier: http://orcid.org/0000-0002-7179-0615
authors.initials: A
authors.lastname: Woolums
mesh_terms: D000208:Acute Disease; D000818:Animals; D018893:Bronchoalveolar Lavage / Q000662:veterinary; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000382:microbiology / Q000821:virology; D017934:Coronavirus; D005260:Female; D045682:Mycoplasma bovis; D009297:Nasal Mucosa / Q000382:microbiology; D009305:Nasopharynx / Q000382:microbiology; D018112:Respiratory Syncytial Virus, Bovine; D012141:Respiratory Tract Infections / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary* / Q000821:virology; D014132:Trachea / Q000382:microbiology
keywords: Bacteria; Diagnosis; Pneumonia; Virus