title: Development and evaluation of a rapid absorbed enzyme immunoassay test for the diagnosis of Johne's disease in cattle.
abstract: An absorbed enzyme immunoassay (EIA) test for Johne's disease in cattle was developed in which absorption of cross-reacting antibodies occurred as a rapid reaction in solution rather than overnight with whole organisms and a subsequent centrifugation step. Total test time was reduced to less than 2 h with a minimum of manipulations. The test was evaluated in cattle herds from Johne's disease-endemic and Johne's disease-free regions of Australia. Specificity was 99.8%. Calculations of sensitivity were affected by the history of the herd under test. However, the EIA detected in excess of 80% of animals before onset of clinical disease and 65% of faecal shedders were EIA positive on, or before, first detection of Mycobacterium paratuberculosis in their faeces. The test should aid epidemiological studies and be a useful tool in the management and control of Johne's disease.
authors.affiliation: Commonwealth Serum Laboratories, Parkville, Victoria.
authors.forename: J C
authors.initials: JC
authors.lastname: Cox
authors.forename: D P
authors.initials: DP
authors.lastname: Drane
authors.forename: S L
authors.initials: SL
authors.lastname: Jones
authors.forename: S
authors.initials: S
authors.lastname: Ridge
authors.forename: A R
authors.initials: AR
authors.lastname: Milner
mesh_terms: D000042:Absorption; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology*; D002417:Cattle; D005069:Evaluation Studies as Topic; D005243:Feces / Q000382:microbiology; D007106:Immune Sera / Q000276:immunology; D007124:Immunoenzyme Techniques; D009161:Mycobacterium / Q000276:immunology* / Q000302:isolation & purification; D009162:Mycobacterium avium / Q000276:immunology; D010283:Paratuberculosis / Q000175:diagnosis* / Q000382:microbiology; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic / Q000662:veterinary
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007106:Immune Sera; D011933:Reagent Kits, Diagnostic