Evaluation of PMS-PCR technology for detection of Mycobacterium avium subsp. paratuberculosis directly from bovine fecal specimens.

Mycobacterium avium subsp. paratuberculosis (MAP) causes paratuberculosis, or Johne's disease, in animals. Diagnosis of MAP infection is challenging because of the pathogen's fastidious in vitro growth requirements and low-level intermittent shedding in feces during the preclinical phase of the infection. Detection of these "low-shedders" is important for effective control of paratuberculosis as these animals serve as sources of infection for susceptible calves. Magnetic separation technology, used in combination with culture or molecular methods for the isolation and detection of pathogenic bacteria, enhances the analytical sensitivity and specificity of detection methods. The aim of the present study was to evaluate peptide-mediated magnetic separation (PMS) capture technology coupled with IS900 PCR using the Roche real-time PCR system (PMS-PCR), in comparison with fecal culture using BACTEC-MGIT 960 system, for detection of MAP in bovine fecal samples. Among the 351 fecal samples 74.9% (263/351) were PMS-PCR positive while only 12.3% (43/351) were MGIT culture-positive (p=0.0001). All 43 MGIT culture-positive samples were also positive by PMS-PCR. Mean PMS-PCR crossing-point (Cp) values for the 13 fecal samples with the highest number of MAP, based on time to detection, (26.3) were significantly lower than for the 17 fecal samples with <100 MAP per 2g feces (30.06) (p<0.05). PMS-PCR technology provided results in a shorter time and yielded a higher number of positive results than MGIT culture. Earlier and faster detection of animals shedding MAP by PMS-PCR should significantly strengthen control efforts for MAP-infected cattle herds by helping to limit infection transmission at earlier stages of the infection.

Salgado M ，Steuer P ，Troncoso E ，Collins MT ... -  《-》

Improvement of sensitivity for Mycobacterium avium subsp. paratuberculosis (MAP) detection in bovine fecal samples by specific duplex F57/IC real-time and conventional IS900 PCRs after solid culture enrichment.

Fawzy A ，Eisenberg T ，El-Sayed A ，Zschöck M ... -  《-》

Detection of Mycobacterium avium subspecies paratuberculosis: comparing fecal culture versus serum enzyme-linked immunosorbent assay and direct fecal polymerase chain reaction.

Clark DL Jr ，Koziczkowski JJ ，Radcliff RP ，Carlson RA ，Ellingson JL ... -  《-》

High-throughput direct fecal PCR assay for detection of Mycobacterium avium subsp. paratuberculosis in sheep and cattle.

Plain KM ，Marsh IB ，Waldron AM ，Galea F ，Whittington AM ，Saunders VF ，Begg DJ ，de Silva K ，Purdie AC ，Whittington RJ ... -  《-》

An efficient DNA extraction method for polymerase chain reaction-based detection of Mycobacterium avium subspecies paratuberculosis in bovine fecal samples.

Zhang MZ ，Zhang S 《-》