title: Pathologic characterization of genotypes XIV and XVII Newcastle disease viruses and efficacy of classical vaccination on specific pathogen-free birds.
abstract: To characterize the clinicopathologic features of recently described genotypes of Newcastle disease virus (NDV), 1 representative strain of genotype XIV and 2 of genotype XVII, all isolated from West Africa, were used to infect groups of ten 4-week-old specific pathogen-free chickens. The pathobiology of these 3 strains was compared to a South African NDV strain classified within genotype VII. All chickens infected with the 4 viruses died or were euthanized by day 4 postinfection due to the severity of clinical signs. Gross and histologic lesions in all infected chickens included extensive necrosis of lymphoid tissues (thymus, spleen, bursa of Fabricius, cecal tonsils, gut-associated lymphoid tissue), gastrointestinal necrosis and hemorrhages, and severe hemorrhagic conjunctivitis. Immunohistochemical staining revealed systemic viral distribution, and the most intense staining was in the lymphoid organs. Results demonstrate that the 3 West African strains from the previously uncharacterized genotypes XIV and XVII are typical velogenic viscerotropic NDV strains with lesions similar to the South African strain. Under experimental conditions, QV4 and LaSota NDV vaccine strains successfully protected chickens from morbidity and mortality against the genotype VII and one genotype XVII NDV strain, with no significant differences in the amount of virus shed when 2 vaccine schemes were compared.
authors: Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, Athens, GA, USA Leonardo.susta@ars.usda.gov lsusta1@gmail.com.
authors: L
authors: L
authors: Susta
authors: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
authors: M E B
authors: ME
authors: Jones
authors: OIE/FAO Reference Laboratory for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, Padua, Italy.
authors: G
authors: G
authors: Cattoli
authors: Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, Athens, GA, USA.
authors: S
authors: S
authors: Cardenas-Garcia
authors: Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, Athens, GA, USA.
authors: P J
authors: PJ
authors: Miller
authors: Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
authors: C C
authors: CC
authors: Brown
authors: Exotic and Emerging Avian Viral Diseases Research Unit, Southeast Poultry Research Laboratory, Athens, GA, USA.
authors: C L
authors: CL
authors: Afonso
mesh_terms: D000818:Animals; D002645:Chickens; D005838:Genotype; D008221:Lymphoid Tissue / Q000473:pathology / Q000821:virology; D009521:Newcastle Disease / Q000473:pathology* / Q000821:virology; D009522:Newcastle disease virus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D011201:Poultry Diseases / Q000473:pathology* / Q000821:virology; D013047:Specific Pathogen-Free Organisms
keywords: West Africa; chickens; clinicopathologic assessment; genotypes XIV and XVII; heterologous vaccination; pathogenesis; velogenic viscerotropic Newcastle disease virus