title: Associations between health and productivity in cow-calf beef herds and persistent infection with bovine viral diarrhea virus, antibodies against bovine viral diarrhea virus, or antibodies against infectious bovine rhinotracheitis virus in calves.
abstract: OBJECTIVE
  To measure associations between health and productivity in cow-calf beef herds and persistent infection with bovine viral diarrhea virus (BVDV), antibodies against BVDV, or antibodies against infectious bovine rhinotracheitis (IBR) virus in calves.
  
  
  METHODS
  1,782 calves from 61 beef herds.
  
  
  METHODS
  Calf serum samples were analyzed at weaning for antibodies against type 1 and type 2 BVDV and IBR virus. Skin biopsy specimens from 5,704 weaned calves were tested immunohistochemically to identify persistently infected (PI) calves. Herd production records and individual calf treatment and weaning weight records were collected.
  
  
  RESULTS
  There was no association between the proportion of calves with antibodies against BVDV or IBR virus and herd prevalence of abortion, stillbirth, calf death, or nonpregnancy. Calf death risk was higher in herds in which a PI calf was detected, and PI calves were more likely to be treated and typically weighed substantially less than herdmates at weaning. Calves with high antibody titers suggesting exposure to BVDV typically weighed less than calves that had no evidence of exposure.
  
  
  CONCLUSIONS
  BVDV infection, as indicated by the presence of PI calves and serologic evidence of infection in weaned calves, appeared to have the most substantial effect on productivity because of higher calf death risk and treatment risk and lower calf weaning weight.
authors.affiliation: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Waldner
authors.forename: Richard I
authors.initials: RI
authors.lastname: Kennedy
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D000914:Antibodies, Viral / Q000097:blood; D001706:Biopsy / Q000662:veterinary; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000453:epidemiology / Q000276:immunology*; D002353:Carrier State / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary / Q000821:virology; D002417:Cattle / Q000254:growth & development* / Q000276:immunology; D030241:Diarrhea Virus 1, Bovine Viral / Q000276:immunology*; D030242:Diarrhea Virus 2, Bovine Viral / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D007150:Immunohistochemistry / Q000662:veterinary; D007241:Infectious Bovine Rhinotracheitis / Q000453:epidemiology / Q000276:immunology*; D009500:Neutralization Tests / Q000662:veterinary; D011247:Pregnancy; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral