Diagnosis of Mycobacterium bovis Infection in Calves Sensitized by Mycobacteria of the avium/intracellulare Group

• DOI: 10.1046/j.1439-0450.2002.00513.x
• Publication Date: 2003-03-12T09:15:25Z
• Authors: M. AMADORI; S. TAGLIABUE; S. LAUZI; G. FINAZZI; G. LOMBARDI; P. TELÒ; L. PACCIARINI; L. BONIZZI
• Keywords: DNA, Bacterial; Tuberculin Test; Fluorescent Antibody Technique; Enzyme-Linked Immunosorbent Assay; 04 agricultural and veterinary sciences; Flow Cytometry; Antibodies, Bacterial; Mycobacterium bovis; Polymerase Chain Reaction; Sensitivity and Specificity; 3. Good health; 0403 veterinary science; Interferon-gamma; Nasal Mucosa; Bacterial Vaccines; Leukocytes, Mononuclear; Animals; Cattle; Tuberculosis, Bovine; DNA Primers; Mycobacterium avium

Because of the frequent exposure cattle to mycobacteria avium/intracellulare group, an investigation was carried out into possible repercussions thereof on diagnosis bovine tuberculosis. Three calves from a tuberculosis‐free herd, scored avian reactors in γ‐interferon assay for tuberculosis, were sedated and inoculated endotracheally with virulent Mycobacterium bovis strain. Then, three other housed above donor calves. isolated nasal swabs infected, On these samples, TB complex‐specific polymerase chain reaction (PCR) tests IS6110 also positive, albeit different time kinetics. The contact‐infected showed clear immunological signs infection; however, their always PCR‐negative only avium isolated. In infected there rise responses purified protein derivative (PPD) tuberculins, which reached same stable plateau levels over whole experiment. effect observed calves, even though response PPD tuberculin remained at higher level. By using conventional comparative intradermal test generally positive as opposed calves; M. obtained two by tuberculins based bacillus Calmette‐Guerin (BCG) secreted or somatic antigens. It concluded that infection may be concealed some sensitized group diagnostic procedures should adopted such animals.