Correlation between foot-and-mouth disease virus antigenic mass, titer and immune response in vaccinated sheep

The antigen mass load of foot-and-mouth disease virus (FMDV) is one of the critical clues to produce a potent vaccine. In the current work, the quantification of the virus 146S antigen content was described and the relationship between antigen mass in the vaccine and the immune response to FMDV in vaccinated sheep were investigated. It was found that FMD vaccine containing at least 1.5 µg/2ml (small ruminant dose) or 3 µg/2ml (cattle and buffaloes dose) from each serotype of FMDV 146S particles and virus titers 6.55-7.3 log10 TCID50/ml gave protective immune response against FMDV. Moreover, relying on the antigenic mass coupled to ultrafiltration of the virus was showed to be of better quality and potency than depending on the volume of the virus suspensions in the formulation of FMD vaccine; however, the former technology needs with standing more cost and effort .