Horizontal transmission experiment of paratuberculosis

摘要: In September 2001 two groups of 5 calves were placed between 6 infectious cows in a row during 3 months (Period 1). Calves one week old at the start and born MAP-unsuspected status-10 herds. Cows artificially (orally) infected month age Januari 1999. Each calf was housed an open box (to avoid injuries) cows, their position randomly changed every weeks. not by us. During second period months, each group together with new (one start) separate group-stable 2). Every weeks Period 1 2 blood faecal samples taken all animals. After this period, 20 transferred to farm (only crops, no other animals) dividing walls direct or contact (until summer 2005). autumn 2004 animals inseminated.Results test-positive will be shown. Horizontal cow-calf transmission seems easy At highest infection pressure (6 shedding which continuously 1) excreted MAP faeces (shortly after infection), also (when absent). that, excretion declined. calf-calf did take place The rate (reproduction ratio R0) quantified end experiment, because more can still become faecal-culture positive, especially shortly before calving (summer 2005)