야외분리 뉴캣슬병바이러스 성상에 대한 비교연구

Comparative studies of newcastle disease virus I. Characterization of the virus

Two strains of Newcastle disease virus isolated in 1950 and 1989 were investigated for biological, physical and chemical characters. The 2 isolates were identified as velogenic type strains on the basis of emtryo mean death times and the relative lack of pathogenicity for day old chicks and 6-week old chickens. The treatment of the viruses in phosphate buffer of pH 3.0 and pH 7.0 showed the difference for infectivity. Various degrees of cross reaction between two strains of Newcastle disease virus were observed. Hemagglutinin activity of Newcastle disease virus isolated for mammalian erythrocytes seemed to have same characters.