Parthiban, SJohn Kirubaharan, JRamesh, AVidhya, M; et al.TANUVAS2020-03-062020-03-062020-02http://krishikosh.egranth.ac.in/handle/1/5810144355TNV_20thMVC_PP_Feb-2020_OP65Newcastle disease (ND) is a standout amongst the most significant diseases of poultry throughout the world. The disease is associated with serious respiratory, gastrointestinal, and neurological lesions in chicken. The etiological agent of the disease is an Avian avulavirus 1, synonymously referred as Newcastle disease virus (NDV). In vivo pathogenicity assaying is sensitive and specific pathotyping tools for detection and identification of NDV used until the recent past. In this study twelve NDV isolates (Isolate numbers 463, 464, 475, 476, 122-17C, 122-17D, 122-17E, 128-17A, 128-17D, 137, 139, 141) available in the department of Veterinary Microbiology, Madras Veterinary College (MVC), Chennai are subjected for pathotyping using mean death time (MDT) in specific pathogen free (SPF) embryonated eggs and TaqMan minor groove binding (MGB) probe real time PCR assay. Pathotyping based on the MDT revealed two NDV isolates (isolate no. 476 and 128-17D) as velogenic strains and remaining ten NDV isolates as lentogenic strains. Pathotyping based on TaqMan MGB probe real time PCR assay revealed six NDV isolates (476, 128-17D, 463, 464, 475, 137) as velogenic/mesosogenic strains and remaing six NDV isolates (122-17C, 122-17D, 122-17E 128-17A, 139, 141) as lentogenic strains. Four NDV isolates (463, 464, 475, 137) which are pathotyped as lentogenic strains by MDT were pathotyped as velogenic/mesosogenic strains by real time PCR assay this shows the higher sensitivity of TaqMan MGB probe real time PCR assay in pathotyping of NDV over conventional MDT.enVeterinary SciencePresentation