Immune protection assay of Newcastle disease live vaccine （LaSota Strain） against a genotype VII NDV isolate
Abstract：A NDV isolate SDLY01 was isolated from the chicken of Shandong Province. SDLY01 was determined as a virulent strain with MDT after plague-purification. Phylogenetic analysis showed SDLY01 isolate belonged to the genotype VII linkage. Twenty seven-day-old SPF chickens were vaccinated with NDV live vaccine （LaSota strain） intranasally and intraocularly. Twenty SPF chickens non-vaccinated were served as control. At 21 days of age, chickens were challenged with virus F48E8 or SDLY01 respectively. The chickens in control group began to show clinical signs of ND and died between 2 and 4 days after challenge. No signs of ND were observed in the immunized chickens. Virus was isolated from tracheal and cloacal swabs collected from chickens challenged with SDLY01 at 5 days post-challenge. No virus was detected from chichens challenged with F48ES. The results showed that LDLY01 could replicated in the vaccinated chickens although LaSota vaccine could protect chickens against the challenge with SDLY01 or F48E8.
Keywords：Newcastle diseaseLive vaccineGenotype VIIIsolateInmmune protection
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：2( 34-35 )