Prevalence of paratuberculosis infection in sheep

Paratuberculosis is an incurable chronic disease of ruminants, which is manifested with clinical signs of diarrhea and progressive weight loss. Causative agent is Mycobacterium avium subsp. paratuberculosis, and the disiase occurs in cattle, sheep and goats. The outspread of paratuberculosis is huge in the whole world, especially in the countries where animal breeding is a developed branch of economy. Animals get infected with food and water contaminated with feces of infected animals. The infection spreads within infected pastures and also when trading animals with latent infection. Clinical manifestation of the disease can firstly be noticed in young categories of sheep, which is different than in cattle. Primary clinical symptom is chronic weight loss. It is rather hard to determine the level of prevalence of the disease, in a certain region, because the diagnostic procedure is complex and not always reliable enough. Detection of antibodies with ELISA test is considered a method of choice for diagnostic of paratuberculosis, because of fast gaining of the results and relatively low price of the test. By applying the ELISA test, we have analysed 2000 sheep blood samples. Positive results for paratuberculosis were found in 66 ( 3,30%) animals in total. In sheep samples from southern Backa region, positive findings were gained from 42 (3,89%) samples, and in Srem region, positive finding were found in samples from 24 sheep (2,60%). Control programs are based on the removal of all infected animals, application of general preventive measures and vaccination. Application of vaccination aims for elimination of clinical form of the disease. An effective treatment has not been determined so far.