title: Informative value of an indirect enzyme-linked immunosorbent assay (ELISA) for the detection of bovine viral diarrhoea virus (BVDV) antibodies in milk.
abstract: Bulk and individual milk samples from 117 herds located in Brittany (west France) were used to assess: (i) the performance characteristics of an indirect enzyme-linked immunosorbent assay (ELISA) applied to individual milk for the detection of antibodies to bovine viral diarrhoea virus (BVDV); and (ii) the relationship between the bulk milk result obtained from this test and the within-herd prevalence of antibody-positive lactating cows. This ELISA test was based on a monoclonal antibody directed against non-structural protein NS2-3 of pestiviruses. At the individual level, based on 1113 matched milk/serum samples, the sensitivity and specificity of this test applied to milk, compared with the virus neutralization test on serum, were 95.0 and 97.7%, respectively. At the herd level, the relationship between the optical density percentage (OD%) of bulk milk and the within-herd prevalence of antibody-positive lactating cows was assessed using the receiver operating characteristics (ROC) analysis. Classes of OD% of bulk milk were determined so that they were associated with minimum intraclass and maximum between-class variances of within-herd prevalence of antibody-positive cows. The ROC analysis resulted in two classes of bulk milk results corresponding to different expected levels of within-herd prevalence. Herds with an OD% of bulk milk < 75% and > or = 75% had a mean observed prevalence of antibody-positive cows of 8.9 and 60.6%, respectively. Herds with a bulk milk result < 75% were expected to be BVDV free, whereas large variations in prevalence of antibody-positive cows existed in the herds with OD% > or = 75%. The test described in this study is suitable to identify herds likely to have a low prevalence of BVDV antibody-positive cows.
authors.affiliation: Unit of Animal Health Management, Veterinary School-INRA, Nantes, France.
authors.forename: F
authors.initials: F
authors.lastname: Beaudeau
authors.forename: C
authors.initials: C
authors.lastname: Belloc
authors.forename: H
authors.initials: H
authors.lastname: Seegers
authors.forename: S
authors.initials: S
authors.lastname: Assié
authors.forename: P
authors.initials: P
authors.lastname: Pourquier
authors.forename: A
authors.initials: A
authors.lastname: Joly
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis*; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000175:diagnosis* / Q000276:immunology; D002417:Cattle; D001908:Diarrhea Viruses, Bovine Viral / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D005260:Female; D008892:Milk / Q000276:immunology*; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D000914:Antibodies, Viral