RATE AND STRUCTURE OF CATTLE TRANSFERS BETWEEN CATTLE HERDS CONSIDERED TO BE FREE OF PARATUBERCULOSIS

摘要

The rate and structure of cattle transfers between 206 Dutch cattle herds, with a 'Mycobacterium avium subsp. paratuberculosis (Mop)-free' status by November 2002, were analysed over a three-year period (November 1999 -November 2002). Of the 206 'Mop-free' herds, 184 were closed herds. In total, 280 cattle had been introduced into 22 herds at an average rate of 0.33 per year per 100 animals present in the 206 herds. Forty-four of these cattle originated from 12 other 'Mop-free' herds. A further 236cattle, not originating from a 'Mop-free' herd had been introduced before their herds of destination obtained the 'Mop-free' status. The cattle transfers were not randomly distributed over the herds. No cattle were introduced into the 12 herds from whichcattle were transferred to other 'Mop-free' herds. Thus, continued propagation of the infection by cattle transfers was impossible in the group of herds studied during the study period.