Study Of Biology Character Of Chicken NDV And Antigenicity Homology Comparison Of Different Newcastle Disease Virus

Chicken New Castle Disease is one of urgent,highly contagious,violent,virous awin infectious disease which had done great harm to poultry enterprise.It was listed at type A infectious diseaseby OIE.Every year it can cause thousands of millions yuan economic lose.In recent years,there is occurrence continuously in the ND La Sota vaccine immunity and high antibody chicken,some scholars reported its reason with not only immunity method,path,vaccine etc.but also poison and different genotype. At present,classical vaccine strain(genotypeI,II) were I,II(B1),III(F),IV(Lasota)and V4,ect.but prevail virus were classed to genotype VI,VII,VIII,IX.In every prevalence, newly genotype or subotype emergented, which brought suspiction about the prevention and control of ND by few vaccine.In this study,One vitus isolate was obtained from chicken flocks in some farm by biological property,serological tests( HA,HI test)and pathology characteristic study , This virus was identified as high virulence virus. The Antigenicity Homology Comparison of diffderent genotype Newcastle Disease Virus was compared by HI and Cross neutralization test; the reslut clarified why the poultry could not be protected by the vaccine from NDV and the variton of NDV genotype and the diffenrence between in LaSota...