title: Neuropathogenic Capacity of Lentogenic, Mesogenic, and Velogenic Newcastle Disease Virus Strains in Day-Old Chickens.
abstract: Strains of Newcastle disease virus (NDV) have different abilities to elicit neurologic signs. To determine the capacity of different NDV strains to replicate and cause lesions in the brain, independently of their peripheral replication, 1-day-old chickens were inoculated in the subdural space with 7 NDV strains of different virulence (4 velogenic, 2 mesogenic, 1 lentogenic). Velogenic strains induced severe necrotizing and heterophilic ventriculitis and meningitis, as well as edema of the neuroparenchyma, and replicated extensively in the nervous tissue by day 2 postinfection, as demonstrated by immunohistochemistry, when all infected birds died. Clinical signs, microscopic lesions, and viral replication were delayed (days 3 and 4 postinfection) with mesogenic strains. Velogenic and mesogenic NDV strains replicated mainly in neurons, and immunolabeling was first detected in surface-oriented areas (periventricular and submeningeal), possibly as a reflection of the inoculation route. The lentogenic NDV strain did not cause death of infected birds; replication was confined to the epithelium of the ependyma and choroid plexuses; and lesions consisted of lymphoid aggregates limited to the choroid plexuses. Results show that extensive NDV replication in the brain is typical of velogenic and mesogenic, but not lentogenic, NDV strains. In addition, this study suggests that differences in the rate of NDV replication in nervous tissue, not differences in neurotropism, differentiate velogenic from mesogenic NDV strains. This study indicates that intracerebral inoculation might be used as an effective method to study the mechanisms of NDV neuropathogenesis.
authors.affiliation: Animal Pathology, School of Veterinary Medicine and Animal Science, Federal University of Goiás, Goiânia, GO, Brazil College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
authors.forename: V M B D
authors.initials: VM
authors.lastname: Moura
authors.affiliation: Southeast Poultry Research Laboratory, Agricultural Research Service, US Department of Agriculture, Athens, GA, USA Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.
authors.forename: L
authors.initials: L
authors.lastname: Susta
authors.affiliation: Southeast Poultry Research Laboratory, Agricultural Research Service, US Department of Agriculture, Athens, GA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Cardenas-Garcia
authors.affiliation: College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Stanton
authors.affiliation: Southeast Poultry Research Laboratory, Agricultural Research Service, US Department of Agriculture, Athens, GA, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Miller
authors.affiliation: Southeast Poultry Research Laboratory, Agricultural Research Service, US Department of Agriculture, Athens, GA, USA claudio.afonso@ars.usda.gov.
authors.forename: C L
authors.initials: CL
authors.lastname: Afonso
authors.affiliation: College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
authors.forename: C C
authors.initials: CC
authors.lastname: Brown
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D002645:Chickens / Q000821:virology*; D007150:Immunohistochemistry / Q000662:veterinary; D009521:Newcastle Disease / Q000473:pathology* / Q000821:virology; D009522:Newcastle disease virus / Q000472:pathogenicity* / Q000502:physiology; D011201:Poultry Diseases / Q000473:pathology* / Q000821:virology; D014774:Virulence; D014779:Virus Replication
keywords: APMV-1; ICPI; Newcastle disease; brain; chicken; histopathology; immunohistochemistry; neuropathogenesis