title: Response of congenitally immune chicks to viscerotropic velogenic Newcastle disease virus.
abstract: Separate groups of chicks of hen hyperimmune to viscerotropic velogenic Newcastle disease virus (VVNDV) were challenge-exposed to VVNDV by intraocular route at 1 day and 34 days old. Their response was evaluated by clinical symptoms, hemagglutination-inhibition (HI) titers, and virus isolations. Chicks exposed at 1 day old excreted VVNDV from the vent for up to 60 days; their active mean HI titers remained low (10-40); and deaths from VVNDV occurred early (5-16 days) and late (28-55 days). Chicks challenge-exposed at 34 days old excreted virus from the vent for 10 days; active HI titers developed quickly and remained high (891-1177); and deaths and signs of VVNDV occurred early (5-13 days).
mesh_terms: D000818:Animals; D001769:Blood / Q000382:microbiology; D002645:Chickens / Q000276:immunology*; D007112:Immunity, Maternally-Acquired; D009521:Newcastle Disease / Q000276:immunology* / Q000382:microbiology; D009522:Newcastle disease virus / Q000276:immunology* / Q000302:isolation & purification