RESUMO
Mycobacterium avium subsp. paratuberculosis, an acid-fast bacterium is the agent of Johne's disease, an intestinal disease that causes poor nutrient intake in ruminants. During the period 1987-2003, 322 of 777 (41.4%) goat herds and 97 of 458 (21.1%) sheep flocks were found to be infected with M.a.paratuberculosis in Northern Greece. From goats, mycobacteria were isolated from 238 of 652 (36.5%) of intestinal tissues, 14 of 119 (11.8%) of lymph nodes and five of 369 (1.4%) of faecal samples. From sheep, mycobacteria were isolated from 25 of 162 (15.4%) of intestinal tissues, three of 41 (7.3%) of lymph nodes and two of 322 (0.6%) of faecal samples. Isolates were typed by pulsed-field gel electrophoresis (PFGE) and restriction fragment length polymorphism followed by hybridization to IS900 [IS900- restriction fragment-length polymorphism (RFLP)]. IS900-RFLP BstEII profiles C1 and C5 and PFGE profiles [2-19] and [29-15] were identified. These PFGE profiles have not been found outside Greece to date.