title: Genotype characterization of commonly used Newcastle disease virus vaccine strains of India.
abstract: Newcastle disease is an avian pathogen causing severe economic losses to the Indian poultry industry due to recurring outbreaks in vaccinated and unvaccinated flocks. India being an endemic country, advocates vaccination against the virus using lentogenic and mesogenic strains. Two virus strains which are commonly used for vaccination are strain F (a lentogenic virus) and strain R2B (a mesogenic virus). Strain F is given to 0-7 days old chicks and R2B is given to older birds which are around 6-8 weeks old. To understand the genetic makeup of these two strains, a complete genome study and phylogenetic analysis of the F, HN genes of these vaccine strains were carried out. Both the viral strains had a genome length of 15,186 nucleotides and consisted of six genes with conserved complimentary 3' leader and 5' trailer regions. The fusion protein cleavage site of strain F is GGRQGRL and strain R2B is RRQKRF. Although both the viral strains had different virulence attributes, the length of the HN protein was similar with 577 amino acids. Phylogenetic analysis of F, HN and complete genome sequences grouped these two strains in genotype II category which are considered as early genotypes and corroborated with their years of isolation.
authors.affiliation: Division of Veterinary Biotechnology, Indian Veterinary Research Institute, Izatnagar, Bareilly, India.
authors.forename: Sohini
authors.initials: S
authors.lastname: Dey
authors.affiliation: Division of Veterinary Biotechnology, Indian Veterinary Research Institute, Izatnagar, Bareilly, India.
authors.forename: Madhan Mohan
authors.initials: MM
authors.lastname: Chellappa
authors.affiliation: OIE Reference Laboratory for Newcastle Disease, Avian Diseases Section, Animal and Plant Quarantine Agency, Anyang, South Korea.
authors.forename: Satish
authors.initials: S
authors.lastname: Gaikwad
authors.affiliation: Central Avian Research Institute, Izatnagar, Bareilly, India.
authors.forename: Jag Mohan
authors.initials: JM
authors.lastname: Kataria
authors.affiliation: Institute of Marine and Environmental Technology, University of Maryland, Baltimore County, Baltimore, Maryland, United States of America.
authors.forename: Vikram N
authors.initials: VN
authors.lastname: Vakharia
mesh_terms: D000818:Animals; D001717:Birds; D005814:Genes, Viral; D016679:Genome, Viral; D005838:Genotype; D007194:India; D009521:Newcastle Disease / Q000517:prevention & control*; D009522:Newcastle disease virus / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D014765:Viral Vaccines