Mycobacteria Unit routinely performs bacteriological and molecular diagnose of infections produced mainly by members of the Mycobacterium tuberculosis and avium complexes. Moreover, it realizes studies of molecular and epidemiological characterization. The main lines of research are to set up new technologies for the diagnosis (in vivo e in vitro) of the main principal diseases caused by mycobacteria, as well as the development of new technology for molecular characterization studies. The laboratory also designs field studies of control and eradication programs in problem situations for subsequent implementation at a national level. The laboratory also advises Animal Health Services of the Autonomous Communities, farmers and veterinarians, as well as Ministries. In addition as European Union Reference Laboratory for Bovine Tuberculosis, they provide technical and scientific support to all National Reference Laboratories (NRL) and the official veterinary services of the European Union.