[Several criteria of evaluation of foot-and-mouth disease virus reproduced in cell cultures in suspension].

The study of the plaques produced by viruses Asia and O1 reveals different properties which may depend on the virus or on the cell or its method of culture. Antigenic differences and subsequent immunological differences correspond to differences in plaques. On the other hand, the cell line in suspension evolves both in its morphology and its receptivity during the passages. All these variations imply the observations of quantitative and qualitative criteria of evaluation in order to prepare vaccines from viruses similar to viruses specific to a given epizooty.