A comparison of the immune response and respiratory stress effect of three clone sizes of virus and three ranges of aerosol particle size using the lentogenic Newcastle disease vaccine strain AG68L.
The lentogenic Newcastle disease vaccine strain AG68L was used to produce three clones of virus by the selection of large, medium and small plaques which were purified and used as vaccines. The immunising and stress effects on the respiratory tract produced by each clone was determined by measuring the response to aerosol vaccination using monodisperse aerosol clouds. It was found that the clone derived from the small plaque was the least stressing although it retained good immunising qualities. The stress effect was not influenced by the aerosol particle size on which the virus was carried, over the mean particle size range of 1.0 to 4.0 mum.
Allan
W H
WH
Poultry Department, Central Veterinary Laboratory, Weybridge, England.
Borland
L J
LJ