Differentiation of Virulent and Avirulent Strains of New Castle Disease Virus in Shandong Province by RT-PCR and Virology Method

The reverse transcriptase-polymerase chain reaction(RT-PCR) was developed to differentiate virulent and avirulent NDV strains.The RT-PCR and virus detection and differentiation method were both used to detect virulent NDV in 25 samples of tissue homogenized liquids.18 samples were positive both by RT-PCR and virology method.The other 4 samples were positive only by virology method.Another 3 were positive only by RT-PCR.It suggested that more reliable diagnosis result would be achieved by using RT-PCR and the classical virus isolation and identification method together.