Pathology of Aujeszky's disease in mink

Lesions in 21 mink which died of Aujeszky's disease included hemorrhages in lungs, heart, mediastinum, thymus, diaphragm, gastric wall, pancreas, and enteric wall. Microscopically, hyalin and fibrinoid degeneration and necrosis of vessel walls were present in cardiac muscle, brain, gastrointestinal wall and occasionally elsewhere in the body. Hemorrhages, exudation of plasma proteins and necrosis were associated with the angiopathy. Inflammation was minimal or absent. Other findings were congestion and extravasation of blood (lungs, liver), necrosis of lymphoid cells, and hemoglobinuric nephrosis. Aujeszky's disease virus was isolated from all but three animals. After experimental infection of three mink, similar though less pronounced lesions were found to those observed in the field cases.     

Eradication of Aujeszky's disease in Germany

Aujeszky's disease (AD) manifested itself in both German states in 1960. Owing to the historical development, in the subsequent two decades, the development of the disease and of its control in the Western and Eastern parts of Germany went different ways. This article describes differences and particularities in the development of AD in Germany leading to the establishment of a national AD eradication programme after re-unification of the two German states at the beginning of the last decade. The basic principles of the German AD eradication programme are described, and the results of 10 years of efforts to control the disease are presented and discussed. Without any doubt, as in other European countries, implementation of the national eradication programme resulted in a considerable progress in the eradication of AD. Since the eradication programme has been established in 1989, particularly in West Germany, the number of AD outbreaks has decreased steadily from about 2000 cases in 1987 to 0 cases recorded in 2001. Recently, Germany has been declared as officially AD-free by the European Commission.     

Immunoperoxidase study of Aujeszky's disease in pigs

Viral antigen was detected by an immunoperoxidase technique in histological sections from pigs with Aujeszky's disease. The antigen was found mainly in association with focal necrosis in the cerebellum, tonsils, oral and nasal mucosa, salivary glands, lungs, liver, kidneys, pancreas, spleen and adrenal glands. Cells at the margin of the necrotic foci especially were strongly positive. Viral antigen was also demonstrated in the cerebral cortex and in the brain stem. Two types of intranuclear inclusion bodies were found to contain viral antigen and one type also contained viral nucleic acids. Inflammatory cells usually contained no viral antigen. The possible significance of some of these infected tissues in the excretion of the virus is discussed.     

Serological response of pigs infected with Aujeszky's disease virus

The temporal development of antibody in four groups of pigs infected with different Aujeszky's disease virus isolates was examined. The enzyme-linked immunosorbent assay detected antibody by five to six days after infection and the antibody-dependent cell-mediated cytotoxicity assay detected antibody seven to nine days after infection. Neutralising antibody was first detected nine to 10 days after infection, whereas assays measuring complement mediated antibody lysis did not detect antibody until 10 days after infection. These results are discussed in terms of their importance to the diagnosis of and recovery from Aujeszky's disease.