The safety and immunogenicity of an in ovo vaccine against Newcastle disease virus differ between two lines of chicken.
Newcastle disease virus is a major threat to poultry and in ovo vaccines are needed. A live in ovo vaccine for Newcastle disease virus, which was licensed but not marketed, was unsafe. It killed 32% of line 0 chicks and 10% of vaccine Lohmann (VALO) chicks using the maximum recommended dose that infected about 40% of the embryos. VALO's made more antibody than line 0's whether infected in ovo or by contact. The vaccine interrupted the massive development of the air capillaries between injection and hatch 3 days later. Cytokines, delivered as DNA in plasmids, did not function as adjuvants. IFN-gamma prevented infection. IL-4 or IL-18 had little or no effect. Line 0 chicks that had been infected by contact were protected and so the unsafe in ovo vaccination of a minority could protect the majority.
Dilaveris
Dimitrios
D
The Royal Veterinary College, Department of Pathology and Infectious Diseases, Royal College Street, London NW1 OTU, UK.
Chen
Changlin
C
Kaiser
Pete
P
Russell
Peter H
PH
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D002460:Cell Line; D002642:Chick Embryo / Q000254:growth & development; D002645:Chickens / Q000145:classification*; D008168:Lung / Q000254:growth & development; D009521:Newcastle Disease / Q000276:immunology / Q000517:prevention & control; D009522:Newcastle disease virus / Q000276:immunology*; D010063:Ovum; D011201:Poultry Diseases / Q000276:immunology / Q000517:prevention & control; D016896:Treatment Outcome; D014611:Vaccination / Q000662:veterinary*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
D000914:Antibodies, Viral; D014765:Viral Vaccines