Latent class analysis of bulk tank milk PCR and ELISA testing for herd level diagnosis of Mycoplasma bovis.

摘要: The bacterium Mycoplasma bovis causes disease in cattle of all ages. An apparent increase the occurrence M. associated outbreaks among Danish dairy herds since 2011 has prompted a need for knowledge regarding herd-level diagnostic performance. Therefore, objective this study was to evaluate performance an indirect ELISA test by comparison real-time PCR when diagnosing bulk tank milk. Bulk milk samples from (N=3437) were analysed with both antibody detecting BIO K 302 kit and antigen PathoProof Mastitis Major-3 kit. As none these are considered gold standard diagnostics we applied series Bayesian latent class analyses range cut-off values. negative positive predictive values calculated hypothetical true national prevalences (1, 5, 10, 15 20%) infected herds. We estimated that had median sensitivity specificity 60.4 [37.5-96.2 95% Posterior Credibility Interval] 97.3 [94.0-99.8 PCI] at currently recommended (37% Optical density Coefficient). These changed 43.5 [21.1-92.5 99.6 [98.8-100 if increased 50 ODC%. In addition, diagnosis would result fewer false positives value ODC% compared 37 without compromising value.