ABSTRACT
Developments in the diagnosis and treatment of paratuberculosis is constrained by the lack of an experimental animal model. To investigate this problem conventional chicks immunodepressed by a Cyclophosphamide injection and concurrent inoculation of Infectious Bursal Disease Virus (IBDV) were infected with Mycobacterium paratuberculosis and kept for 4 months. The immunodepressed chicks eliminated mycobacteria with their faces from the first month until the third month and developed typical intestinal lesions of mycobacterial infection characterized by aggregation of macrophages with monocytes and lymphocytes. Diarrhoea was absent. The number of lymphocytes decreased by about 80%. The serological tests carried out with Complement Fixation test were negative. For the positive bacteriology and typical granulomatous lesions, the conventionally reared chicks proved to be a useful laboratory model for reproduction of Johne's disease.
Subject(s)
Intestinal Mucosa/pathology , Paratuberculosis/physiopathology , Animals , Bursa of Fabricius/immunology , Bursa of Fabricius/pathology , Chickens , Cyclophosphamide/pharmacology , Disease Models, Animal , Feces/microbiology , Immunosuppression Therapy/methods , Infectious bursal disease virus/immunology , Intestinal Mucosa/immunology , Liver/immunology , Liver/pathology , Lymphocytes/pathology , Macrophages/pathology , Monocytes/pathology , Mycobacterium avium subsp. paratuberculosis/isolation & purification , Necrosis , Paratuberculosis/immunology , Paratuberculosis/pathology , Time FactorsABSTRACT
The presence of Aujeszky's disease virus was investigated in various organs and materials from experimentally infected dogs, employing the fluorescent antibody test (FAT), tissue culture and biological tests in rabbits. The FAT appeared less sensitive for virus detection than virus isolation in cell culture and rabbit tests. The virus distribution in the central nervous system was related to the site of inoculation.