Limited usefulness of the IS touchdown-PCR in blood for tuberculin skin test false-negative cattle with serological response to .

Ante-mortem diagnosis of bovine tuberculosis (bTB) is based mainly on the tuberculin skin test (TST) and the ɣ-IFN release assay (IGRA). Some infected animals escape screening tests, thus, limit herd sanitation. Previous reports have suggested a predominant pattern of multi-organ lesions attributable to (the causative agent of bTB) bacteraemia.