Johne's disease (JD) infection, caused by Mycobacterium avium subsp. paratuberculosis, represents a major disease problem in farmed ruminants. Although JD has been well characterized in cattle and sheep, little is known of the infection dynamics or immunological response in deer. In this study, typing of M. avium subsp. paratuberculosis isolates from intestinal lymphatic tissues from 74 JD-infe...

A new commercial kit for diagnosis of bovine paratuberculosis (Johne's disease), called the Johne's Absorbed EIA (enzyme immunoassay; Commonwealth Serum Laboratories, Parkville, Victoria, Australia), was evaluated by using serum specimens from the National Repository for Paratuberculosis Specimens. The evaluation was specifically designed to measure test sensitivity and specificity for detectio...

Mycobacterium paratuberculosis has been suggested to be involved in the pathogenesis of Crohn's disease (CD). The importance of microorganisms in CD is supported by the association of CD with mutations in the intracellular pathogen recognition receptor (PRR) nucleotide-binding oligomerization domain 2 (NOD2). The aim of this study is to investigate the PRR involved in the recognition of M. para...

Paratuberculosis (Johne's disease) is a fatal disease of ruminants for which no effective treatment is available. Presently, no drugs against Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis), the causative agent of Johne's disease, are approved for use in livestock. Additionally, M. paratuberculosis has been linked to a human chronic granulomatous ileitis (Crohn's disease). To ...

D values (decimal reduction time; the time required to kill 1 log concentration of bacteria) were determined for both human and bovine strains (Dominic, Ben, BO45, and ATCC 19698) of Mycobacterium paratuberculosis in 50 mM lactate solution (pH 6.8) and in milk at four temperatures (62, 65, 68, and 71 degrees C). Viable M. paratuberculosis organisms were quantified by a radiometric culture metho...

Mycobacterium avium subsp. paratuberculosis and Mycobacterium avium subsp. avium are antigenically and genetically similar organisms; however, they differ in their virulence for cattle. M. avium subsp. paratuberculosis causes a chronic intestinal infection leading to a chronic wasting disease termed paratuberculosis or Johne's disease, whereas M. avium subsp. avium causes only a transient infec...

Mycobacterial isolates were obtained by radiometric culture from 33 different species of captive or free-ranging animals (n = 106) and environmental sources (n = 3) from six geographic zones within the United States. The identities of all 109 isolates were confirmed by using mycobactin J dependence and characterization of five well-defined molecular markers, including two integration loci of IS...

Five diagnostic tests based on enzyme-linked immunosorbent assay (ELISA) technology for bovine paratuberculosis were evaluated by using individual serum or milk samples from 359 dairy cattle in seven paratuberculosis-free herds and 2,094 dairy cattle in seven Mycobacterium paratuberculosis-infected dairy herds. Three independent laboratories using three different culture procedures completed fe...

Johne's disease, or paratuberculosis, is a chronic intestinal infection caused by Mycobacterium avium subsp. paratuberculosis. The usually fatal disease is characterised by cachexia, and in some species diarrhoea, after a long pre-clinical phase. Treatment is ineffective and economically impracticable. The infection primarily affects domestic and free-ranging ruminants, but has also been report...

Acid resistance of Mycobacterium paratuberculosis was examined as a function of growth conditions (i.e., in vitro growth medium and pH). M. paratuberculosis was cultured in either fatty acid-containing medium (7H9-OADC) or glycerol-containing medium (WR-GD or 7H9-GD) at two culture pHs (pHs 6.0 and 6.8). Organisms produced in these six medium and pH conditions were then tested for resistance to...