Immunization of Chickens with an Inactivated Oil-Adjuvant Newcastle Disease Virus Vaccine

SUMMARY The preparation of an inactivated oil-adjuvant vaccine of Newcastle Disease virus (NDV) using /8-propiolactone (BPL) is described. The method used also caused inactivation of avian sarcoma viruses. Intramuscular or subcutaneous injections in 4-week-old chickens evoked high levels of hemagglutination-inhibiting (HI) antibodies in the serum which persisted over long periods. It also conferred immunity against challenge with 2 X 105 ELD50 of a virulent strain of NDV administered intramuscularly or by contact.