Isolation and Identification of Newcastle Disease Virus and Partial Biological Characteristics Research in Harbin Area

From April 2012 to April 2014,six viral strains which have hemagglutination activity were isolated from the chicken flocks with suspected newcastle disease(ND) in 18 regions of Harbin.Through the observation results of the HI,HA test and electron microscopy,it was confirmed that these virus were the newcastle disease vrius(NDV).By the biological characteristics study in the plaque purified,it was found that the mean death time(MDT) of chicken embryos and 1 day old chicks intracerebral pathogenicity index(ICPI) were between 37.2~60.8 h and 1.71~1.80,which belongs to the virulent strains or velogenic and mesogenic strains of NDV.