In this study, we examined the effects of recombinant bovine gamma interferon (rIFN-gamma) and nitric oxide (NO) on the interaction of M. avium subsp. paratuberculosis with bovine monocytes. Monocytes pretreated with rIFN-gamma exhibited slightly increased phagocytosis of M. avium subsp. paratuberculosis and modest inhibition of the intracellular growth of this microorganism. The number of viab...

The objective of this study was to determine if experimental infection of neonatal calves with Mycobacterium avium subsp. paratuberculosis would invoke changes in the percentages of total B cells in the peripheral blood mononuclear cell population and of subpopulations of B cells as determined by CD5, CD25, and CD45RO markers during a 12-month period. Experimental infection groups included cont...

Five laboratories participated in a study to evaluate sources of variation in results from an enzyme-linked immunosorbent assay (ELISA) for antibodies against Mycobacterium avium subsp. paratuberculosis. Each laboratory repeatedly tested duplicates of a negative, positive (P), and high-positive (HP) serum sample, which were supplied by the United States Department of Agriculture: Animal and Pla...

A combined molecular and cultural method for the detection of the Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium subsp. paratuberculosis was developed and tested with artificially contaminated milk and dairy products. Results indicate that the method can be used for a reliable detection as a basis for first risk assessments.

Mycobacterium avium subsp. paratuberculosis infection of cattle results in a chronic granulomatous enteritis. Clinical disease (i.e., cachexia, diarrhea, and high fecal bacterial counts) is preceded by a lengthy subclinical stage of disease. The immunologic mechanisms associated with the progression of infected cattle from subclinical to clinical disease are unclear. In this study, a cell proli...

We read with interest the article by Beumer et al. (1) on the detection of Mycobacterium avium subsp. paratuberculosis in 81% of drinking water and biofilm samples by PCR. Although these findings could have a significant influence on our understanding and the potential public impact of M. avium subsp. paratuberculosis as an agent of disease, much of the information on M. avium subsp. paratuberc...

In this study, novel serological tests were used to detect tuberculosis (TB) in groups of farmed red deer (Cervus elaphus) varying in disease status or possible confounding factors. Groups of deer naturally or experimentally infected with Mycobacterium bovis and animals vaccinated against paratuberculosis were studied, as were uninfected animals and animals naturally or experimentally infected ...

CD5 is a cell surface molecule involved in antigen recognition and is present on all T lymphocytes and a subset of B lymphocytes. The purpose of this study was to examine CD5+ expression on peripheral blood B cells from healthy, noninfected cattle and cattle with subclinical and clinical paratuberculosis. Peripheral blood mononuclear cells (PBMC) were freshly isolated or cultured for 7 days in ...

Johne’s Disease or paratuberculosis is a mycobacterial infection of ruminants and has global economical impact. Mycobacterium avium subsp. the cause this disease. It reduces milk production, chronic weight loss leading death major losses. Acute phase reactions are defined as minimum 25% increase decrease in serum concentrations acute proteins which triggered by pro antiinflammatory cytokines re...