Paratuberculosis (Johne's Disease) is an important, chronic, wasting disease of ruminants caused by Mvcobacterium Daratuberculosis. One of the major problems with paratuberculosis is that it is difficult to diagnose until avert clinical disease develops. Economic losses may occur, however, even in cattle with subclinical infections. Our approach to improving the diagnosis of this disease is to develop a DNA probe test which can be used to detect M. Daratuberculosis. We have isolated a 16S ribosomal RNA specific for ~, Daratuberculosis and k[. avium. After optimizing conditions of hybridization, we will use this probe on RNA and on amplified DNA from clinical specimens. The recently developed polymer, se chain reaction will be used to amplify mycobacterial 16S ribosomal RNA genes. At the end of Phase I, we will be able to assess the feasibility of using a direct paratuberculosis DNA probe test on clinical samples.Applications:A sensitive and specific DNA probe test for paratuberculosis could be used in all cattle suspected of having the disease. In addition, it could be used to certify herds as being tparatuberculosis freew and could be used on cattle which are being transported to control the spread of the disease.
