title: Isolation of Avian Pneumoencephalitis (Newcastle Disease) Virus From the Yolk Sac of Four-Day-Old Chicks, Embryos, and Infertile Eggs.
authors.forename: P D
authors.initials: PD
authors.lastname: Delay
mesh_terms: D000818:Animals; D001717:Birds; D002645:Chickens; D004531:Eggs; D009521:Newcastle Disease; D009522:Newcastle disease virus; D015017:Yolk Sac