Aerosol vaccination against Newcastle disease. I. Studies on particle size

Studies revealed that the majority of particles emitted by three different aerosol generators were in the size ranges of 0.5-1 and 1-3 mum. In general, the smaller the aperture setting, the larger the total number of particles. The difference between the generators in number of particles emitted were not significant enough to produce appreciable difference in antibody titers obtained from vaccinated chickens. Antibody titers were higher in birds vaccinated with the LaSota strain of Newcastle disease virus than in birds vaccinated with the B-1 strain, although protection against challenge was approximately similar. Aerosol challenge was found as effective as intramuscular challenge.