title: Prevalence of antibodies against Mycobacterium avium subsp paratuberculosis among beef cow-calf herds.
abstract: OBJECTIVE
  To estimate the prevalence of Mycobacterium avium subsp paratuberculosis infection among cows on beef operations in the United States.
  
  
  METHODS
  Cross-sectional seroprevalence study. Sample Population-A convenience sample of 380 herds in 21 states.
  
  
  METHODS
  Serum samples were obtained from 10,371 cows and tested for antibodies to M avium subsp paratuberculosis with a commercial ELISA. Producers were interviewed to collect data on herd management practices.
  
  
  RESULTS
  30 (7.9%) herds had 1 or more animals for which results of the ELISA were positive; 40 (0.4%) of the individual cow samples yielded positive results. None of the herd management practices studied were found to be associated with whether any animals in the herd would be positive for antibodies to M avium subsp paratuberculosis.
  
  
  CONCLUSIONS
  Results suggest that the prevalence of antibodies to M avium subsp paratuberculosis among beef cows in the United States is low. Herds with seropositive animals were widely distributed geographically.
authors.affiliation: USDA Animal and Plant Health Inspection Service, Centers for Epidemiology and Animal Health, Ft Collins, CO 80521, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Dargatz
authors.forename: B A
authors.initials: BA
authors.lastname: Byrum
authors.forename: S G
authors.initials: SG
authors.lastname: Hennager
authors.forename: L K
authors.initials: LK
authors.lastname: Barber
authors.forename: C A
authors.initials: CA
authors.lastname: Kopral
authors.forename: B A
authors.initials: BA
authors.lastname: Wagner
authors.forename: S J
authors.initials: SJ
authors.lastname: Wells
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D016927:Mycobacterium avium subsp. paratuberculosis / Q000276:immunology*; D010283:Paratuberculosis / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology; D016036:Seroepidemiologic Studies; D014481:United States / Q000453:epidemiology
chemical_list: D000907:Antibodies, Bacterial