Aerosol vaccination against Newcastle disease. II. Effect of vaccine diluents

Three diluents (deionized water, 2% dry milk, and 20% buffered glycerin) were used to suspend the Newcastle disease vaccine for aerosol-vaccination studies. Particle size and the effect on humoral antibody response in chickens was determined for each diluent. For all diluents, the greatest number of particles were found in the size range of 0.5-3 mum. Total particle counts were higher with glycerin than with either milk or water. Antibody response and resistance to challenge, however, were higher with water or milk.