| Summary |
1.Seventy-seven out of 262 cases (29.4%) submitted in 1969, 69 out of 302 cases (22,5%) in 1970, 30 out of 130 cases (23.8%) during first half一year in 1971 were diagnosed as Newcatle disease. The Newcastle disease, 176 out of the total 694 cases diagnosed, was the most important avian diseases in Taiwan.
2. This is the first report to isolate ND virus from turkey, pheasant, silver pheasant, pigeon,duck, and goose of field cases in Taiwan.
3. Very few of ND cases in group of goose_ were observed before. The clinical signs, sinus swelling, coughing, rale, sneezing, cheek swelling, whitish-soft stool, neck trembling, paresis, and recumbent were noted at 11 days alter hatching. Two hundred out of the total 532 geese (38%) were died of the disease.
4. According to the necropsy and clinical signs, the ND cases occurred in chicks, pheasants,pigeons, geese, and turkeys in Taiwan were Asian type.
5. The virus isolated from these birds was velogenic type. The examinations included biochemical properties examination, detection of viral nucleic acid, determination of the Mean Death Time to 10-day-old chicken embryo, determination of Intravenous Pathogenicity Index to 6-week-old chicks.
6. The isolated virus caused a synetial CPE, part of the CPE 、howed round type. A large type of plaque more than 3 mm were manifested. When the isolated 、irus was inoculated onto CK cells, 、ome of the plaque appeared a small type of plaque among the large type of plaque.
7. The total 47 strains isolated from the field cases, 6 of them were contaminated with avian reovirus, and the other 41 were pure ND virus since no Myxovirus Influenza A or Myxovirus Yucaipa were found in them.
8. According to the serologic and immunologic tests, the antigenicity of the collected ND isolates were proved to be homogeneous.
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