In addition, M. avium subsp. paratiiberculosis is a slow-growing organism. Fecal 

 culture on solid media requires 12 to 16 weeks for results. New liquid culture systems 

 have reduced this time to as little as 5 weeks. DNA probes can detect the presence 

 of M. avium subsp. paratuberculosis without its having to be grown. The test has the 

 advantage that it takes less than 3 days but has the disadvantages of higher cost and 

 the potential of missing animals shedding only low quantities of bacteria. 



Various serologic tests, including ELISA, agar-gel immunodiffusion (AGID), and 

 complement fixation, detect antibody in the serum and can be used on a herdwide 

 basis to screen for infection. Although less accurate than fecal culture, these tests are 

 more rapid and less expensive. Serologic tests also work well to confirm clinical cases. 



It is important to note that, as an accredited veterinarian, you should use only the 

 USDA-licensed ELISA tests and USDA-approved laboratories. 



In the dead animal, Johne's disease may be diagnosed by culture and histopathology 

 of the lower small intestine and associated lymph nodes. 



Johne's Disease Control Program 



VS' goal is to curtail the spread of M. avium subsp. paratuberculosis to noninfected 

 herds and to reduce the disease prevalence in herds currently infected. To accomplish 

 this goal, VS has developed a cooperative Federal-State-Industry program that 

 provides producer assistance by performing risk assessments of M. avium subsp. 

 paratuberculosis transmission and developing herd-management plans to mitigate 

 those risks. VS is also working to provide funding for research to develop and validate 

 control measures. Moreover, VS coordinates State activities and monitors current 

 levels of infection in the United States. 



State Governments and Tribal Councils participate by providing personnel to 

 conduct risk assessments and aid in the development of herd-management plans. 

 These agencies also help producers by supporting testing at reduced fees and 

 underwriting other direct program costs. Industry cooperates by encouraging 

 producers to participate in the program through information provided in industry 

 journals and consultation with APHIS and professional societies. 



To work with the lohne's Disease Control Program as an accredited veterinarian, one 

 must first become a Johne's Certified Veterinarian. Johne's Certified Veterinarians 

 have received additional education on the disease and have demonstrated to the 

 State-Designated Johne's Coordinator that they can 



1. Develop approved herd-management plans; 



2. Provide appropriate Johne's disease risk assessments; 



3. Understand Johne's disease epidemiology, testing, and test interpretation; 



4. Understand State and Federal program requirements; and 



5. Collect and submit fecal, tissue, and blood samples for Johne's disease testing. 



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