Stability infectivity of viral vaccines against Newcastle disease (ND) from strains La-Sota and Bor-74 VGNKI, prepared by using the method of granulation and spray-coating in fluidizated bed, was studied during the storage of vaccines at different temperatures. The infectious activity of the vaccines was found to remain stable for 6 months at 4 and 8 degrees C and for 2 weeks at (25 +/- 1) degree C. An analysis of the findings showed that an improved content of the preparation contributed to an essentially increased ND virus thermal stability in the granulated lactose-containing vaccine.