Division 1 IDENTIFICATION OF THE AGENTF1F2

The presence of Mycobacterium bovis (M. bovis) , agent of bovine tuberculosis, in clinical and post-mortem specimens may be demonstrated by examination of stained smears or immunoperoxidase techniques and confirmed by cultivation of the organism on primary isolation medium.

Pathological material for the confirmation of M. bovis should be taken from abnormal lymph nodes and parenchymatous organs such as lungs, liver, spleen, etc. In the cases where the animal does not present pathological lesions, samples from the retropharyngeal, bronchial, mediastinal, supramammary, mandibular and some mesenteric lymph nodes and liver should be collected for examination and culture.

Identification of isolates may be usually carried out by determining cultural and biochemical properties. The polymerase chain reaction (PCR) may also be employed for the detection of the M. tuberculosis complex. DNA analysis techniques may prove to be faster and more reliable than biochemical methods for the differentiation of M. bovis from other members of the M. tuberculosis complex. Genetic fingerprinting allows distinguishing between different strains of M. bovis and will enable patterns of origin, transmission and spread of M. bovis to be described.

The techniques and media used, their standardisation and the interpretation of results must conform to that specified in the OIE Manual of Standards for Diagnostic Tests and Vaccines, Fourth Edition, 2000, Chapter 2.3.3 (bovine tuberculosis).