IMPACT OF PRIOR EXPOSURE TO BOVINE TUBERCULOSIS ON THE RISK OF BOVINE TUBERCULOSIS SKIN TEST REACTIVITY FOR 48,055 CATTLE IN 148 HERDS IN SOUTH WEST ENGLAND

摘要

The aim of this study was to investigate the effect of movement factors on the risk of a bovine animal becoming a reactor at a bovine tuberculosis (bTB) herd skin test. Using data from 148 study farms, individual animal records were created by interrogating the national movement database and the bTB testing databases, and were corroborated with data collected at farm visits. Study farms, 24% of which were restocked due to the foot and mouth disease (FMD) outbreak in 2001, were located in six countiesof the south west of England. All farms participated in the Randomised Badger Culling Trial (RBCT) trial areas (the Kreb's trial). Cattle were more likely to react to the bTB skin test when they had been present at a previous test or tests where a bovine / cattle had reacted to the skin test, highlighting the importance of infected cattle as a main source of infection to other cattle on the same farm or another farm if moved when infected but undetected.