Submitted to: National Cattlemens Beef Association Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: February 3, 1998
Publication Date: N/A
Technical Abstract: Diagnosis of paratuberculosis is difficult because of the fastidious growth pattern of the microorganism and because of the paradoxical immune response of the host animal to infection. In the early subclinical stages of infection, the microorganism elicits a cell-mediated response by stimulation of the host T lymphocytes. As disease progresses from subclinical to clinical stages, the cell-mediated immune response wanes an a strong humoral response controlled by B lymphocytes predominates. The presence of antibody to Mycobacterium paratuberculosis does not protect the host against the disease; indeed, active cell-mediated immunity appears to be essential to keep the infection in check. In the final stages of disease, lack of antigen-specific, cell-mediated immune response or complete anergy may result allowing for rapid dissemination of the infection throughout the host. This report details the usefulness of current diagnostic tests for detection of paratuberculosis in ruminants.