Diagnóstico de tuberculosis en rumiantes y camélidos

Tuberculosis is a bacterial zoonosis that represents an important health problem in humans, domestic animals and wildlife. The most frequently involved species in animal tuberculosis are Mycobacterium bovis and M. caprae. The disease has a major economic impact caused by the decreased production in animals, the commercial restrictions implied, and the costs of eradication campaigns in cattle. In the last years, tuberculosis is gaining relevance in other domestic species i.e. goats, mainly in those countries with a high census of this species. Additionally, tuberculosis in South American camelids is increasingly gaining importance in recent years, llamas (Lama glama) and alpacas (Vicugna pacos) are main species imported into the European Union. Eradication campaigns are based on "test-andslaughter" strategies which implies the removal of animals that react positively to diagnostic tests. The official diagnostic tests approved in the European Union are the single intradermal tuberculin (SIT) test and the interferon-gamma (IFN-γ) assay, which detect the cell-mediated immune response to the pathogen. Serological assays for the detection of antibodies are also available, commercially and/or experimentally. Despite of the efforts performed for the control and the eradication of the disease, in some areas it is not possible to decrease the prevalence due among others, to the limitations present in the official diagnostic techniques. Therefore, in order to optimize the diagnosis of tuberculosis in ruminants (cattle and goats) and camelids (llamas and alpacas), nine experimental studies divided into five chapters have been performed, each chapter has been designed to achieve the five objectives of this thesis ...