| Pigeon Paramyxovirus 1 (PPMV-1), so-called pigeon plague, caused by ND virus (NDV), is a serious illness of poultry. It has a high morbidity and mortality. The clinical signs were characterized by bilateral conjunctivitis and neurological. It's the biggest trouble maker of the development of the poultry industry, and invokes trade barriers and causes significant economic losses in the commercial poultry industry. According to the Office of International Epizootes (OIE), ND belong to the reportable list A diseases. In the past 2 decades, due to a strict vaccination program, occurrences of ND were mild and sporadic and caused few deaths in poultry flocks in China. The sporadic cases, showing no typical clinical and pathological manifestation of the disease, were named "atypical ND". For PPMV-1's velogenic and variant, NDV vaccine can't offord 100% protection. It often took place here and there in some immune or unimmune poultry farms. Base on its pathogenicty to the pigeons and chicken, PPMV-1 strains were classified into three groups: velogenic to pigeon but lentogenic to chicken; velogenic to both; and lowly pathogenic categories even to the baby pigeons or chickens. Now there is at least three genotypes(â…¡,â…¥,and â…¦) exists in China. In this study, a pigeon-origin NDV isolate was investigated for its...
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