Thirty-day-old piglets were intranasally or subcutaneously inoculated with 2ml of Aujeszky´s disease virus, NYJ-1 strain, at the titer of 106^(6.75) TCID_(50)/0.l㎕, that was isolated from the diseased piglets in Korea, and histopathological studies were performed to elucidate the pathognomonic characters of the isolate.
Results obtained through the experiments were as follows:
1. Major clinical signs on the 2nd and 3rd days post inoculation (p.i.) were fever, anorexia and dyspnea, On the 6th and 7th days p.i., nervous signs, severe dyspnea and salivation were observed in the group of intranasal inoculation, and one out of 3 piglets in this group died on the 7th day p.i.. General signs were more severe in the group of intranasal inoculation than the group of subcntaneous injection. Between the 8th and l0th days p.i., the signs subsided and the piglets were completely recovered from the illness.
2. Hematologically, most of the inoculated pigs showed a mild lymphocytopenia on the 5th and 6th days p.i..
3. By necropsy, swelling and hemorrhagic lesions were observed in tonsil, central nervous system and lung, No specific changes were grossly found in other parenchymatous organs.
4. In histopathological study, degeneration and necrosis of nervous cells, non-suppurative meningoencephalitis, diffuse or focal gliosis, perivascular cutting and degeneration of ganglion cells were observed in central nervous system, and swelling and hemorrhagic changes were shown in the tissues of liver, lung and lymph nodes.
5. By indirect immunofluorescence antibody assay using ADV-monoclonal antibody, specific ADV antigens were detected in the tissues of tonsil, brain and spleen of the succumbed piglet. However, in the experimentally slaughtered piglets, the specific reactions were noted only in the tonsils.
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