Para tuberculosis (Johnes disease): Basic characteristics and current situation locally

Abstract

Para tuberculosis or Johne's Disease, is a disease of the digestive tract of animals caused by Mycobacterium avium subspecies Para tuberculosis (M. a. Para tuberculosis). Para tuberculosis has been registered in many countries and it today presents one of the most widely-spread bacterial diseases in ruminants that causes severe economic damages. In our country, Para tuberculosis has not been studied extensively. The disease was registered for the first time in Serbia in 1995 in an isolated herd of sheep of the II-de-France breed, and serologically positive cattle were determined in 2001. Infection with M.a. Para tuberculosis occurs mostly in young animals which are the most sensitive to infection. The main source of infection is the feces of diseased animals. Furthermore, colostrums and milk of diseased animals can contain micro bacteria, and there is a possibility also of intra-uterine infection. A long period of incubation, a chronic course, and not always clear clinical picture render diagnosis of Para tuberculosis very complex, in spite of the existence of numerous diagnostic methods. There are a number of serological tests with which it is possible to detect antibodies against M.a. Para tuberculosis in infected animals. The most frequently used are complement binding reaction (CBR), the agar gel immunodiffusion test (AGID), and the immunioenzyme test (ELISA). The isolation of causes or parts of their genome, present important methods in the diagnosis of Para tuberculosis. Pieces of tissue obtained through autopsies or biopsies, feces or milk samples, can serve as material for isolation. A diagnosis of Para tuberculosis for dead or sacrificed animals is made on the grounds of path anatomical or path histological findings. Para tuberculosis of ruminants has certain similarities with Crohn's Disease in humans, from the clinical, morphological, and etiological aspects.

Paratuberkuloza ili Johneova bolest je oboljenje digestivnog trakta životinja, prouzrokovano Mycobacterium avium subspecies paratuberculosis (M.a. paratuberculosis). Paratuberkuloza je ustanovljena u mnogim zemljama i ona danas predstavlja jednu od najrasprostranjenijih bolesti bakterijske etiologije preživara koja uzrokuje velike ekonomske štete. U našoj zemlji paratuberkuloza nije opsežnije izučavana. U Srbiji je prvi put bolest otkrivena 1995. godine u jednom izolovanom stadu ovaca rase Il de France, a serološki pozitivna goveda 2001. godine. Infekcija izazvana bakterijom M.a. paratuberculosis nastaje, uglavnom, kod mladih životinja koje su na infekciju i najosetljivije. Osnovni izvor infekcije je feces bolesnih životinja. Takođe, kolostrum i mleko obolelih životinja mogu da sadrže mikobakterije, a postoji mogućnost i intrauterine infekcije. Duga inkubacija, hronični tok i ne baš uvek jasno ispoljena klinička slika, čine dijagnostiku paratuberkuloze veoma kompleksnom i pored postojanja velikog broja dijagnostičkih metoda. Postoji nekoliko seroloških testova pomoću kojih je moguće da se otkriju antitela protiv M. a. paratuberculosis kod inficiranih životinja. Najčešće se koriste reakcija vezivanja komplementa (RVK), agar-gel imunodifuzioni test (AGID) i imunoenzimski test (ELISA). Izolacija uzročnika ili delova njegovog genoma, predstavljaju važne metode u dijagnostikovanju paratuberkuloze. Materijal za izolaciju mogu da budu delovi tkiva dobijeni obdukcijom ili biopsijom, feces i uzorci mleka. Dijagnoza paratuberkuloze na uginulim ili žrtvovanim životinjama postavlja se na osnovu patoanatomskog i patohistološkog nalaza. Paratuberkuloza preživara u kliničkom, morfološkom i etiološkom aspektu ima izvesne sličnosti sa Crohnovom bolesti ljudi.