Velogenic strains of Newcastle disease virus (NDV) cause Newcastle disease (ND), a devastating disease of poultry and wild birds. Phylogenetic analysis of recent Egyptian isolates in Menofia governorate, Egypt was constructed, and showed to be of genotype VII. Eight NDV viruses were isolated from vaccinated commercial broiler flocks showing respiratory manifestation in Menofia governorate, Egypt during 2019. Those viruses showing deaths and haemorages of inoculated SPF ECE eggs, harvested allantoic fluids showed haemagglutination activity by using 1% RBCs and also haemagglutination inhibition in case of using NDV reference antiserum, As well as realtime polymerase chain reaction by using standardized NDV specific primers and finally eight viruses were selected for further sequencing for the partial fusion protein, The eight NDVs isolates of velogenic genotype VII and contain the unique cleavage site motif 112RRQKRF117 with high relation to very virulent NDV Chinese strain Chicken /China/SDWF07/2011 strain with nucleotide identity percentage (99.3% -100%). The main causative agent of recent ND outbreaks in vaccinated broiler flocks in Menofia governorate, Egypt was found to belong to very virulent genotype VII. This strain was genetically identical to Egyptian genotype VII isolates isolated in the last period.
To share on other social networks, click on any share button. What are these?