Evaluation of Environmental Sampling to Determine Distribution and Dairy Herd Infection Status for Mycobacterium avium subspecies paratuberculosis

摘要

An important component of the Voluntary Bovine Johne's Disease Control Program is to determine herd infection status for Mycobacterium avium subspecies paratuberculosis (MAP). To help prevent the transmission of MAP, dairy and beef herds providing replacement cattle should know their infection status. Herds acquiring cattle should be fairly confident that the source herd is at low risk for MAP infection. The current requirements for a herd to be considered Level 1 of the test-negative component requires ELISA testing 30 animals followed by fecal culture confirmation of ELISA-positive cattle. Since the ELISA is approximately 25-50% sensitive, many infected herds are classified as low risk and enter Level 1 based on this testing scheme.