title: Comparison of techniques for the detection of avian infectious bronchitis virus as a contaminant of vaccines.
abstract: Techniques for detecting various levels of both field and vaccine strains of infectious bronchitis virus in a deliberately contaminated Newcastle disease vaccine were compared using chick embryos, chick kidney cells, chick tracheal organ cultures and chickens with a view to determining the most appropriate method for screening vaccines for freedom from IBV contamination. Techniques examined included detection of abnormalities and deaths in embryos, cytopathic effect in chick kidney cells, ciliostasis in chick tracheal organ cultures and clinical signs and virus isolation in chickens as well as the fluorescent antibody test, negative contrast electron microscopy and serology where appropriate. Results showed that the techniques capable of detecting both strains of infectious bronchitis virus were, in order of sensitivity, the fluorescent antibody test on allantoic cells from infected embryos, ciliostasis and direct electron microscopy of allantoic fluid. One surprising feature was the poor results obtained using chickens. Some detection was achieved with tracheal virus isolation and tracheal organ cultures prepared from inoculated birds and to a lesser extent with histology and clinical signs, but no technique detected the field strain.
mesh_terms: D000818:Animals; D002645:Chickens; D003332:Coronaviridae / Q000302:isolation & purification*; D004340:Drug Contamination; D005455:Fluorescent Antibody Technique; D001351:Infectious bronchitis virus / Q000302:isolation & purification*; D008854:Microscopy, Electron; D009522:Newcastle disease virus / Q000276:immunology; D014765:Viral Vaccines / Q000032:analysis*; D014776:Virus Cultivation
chemical_list: D014765:Viral Vaccines