Seroconversion of three different foot-and-mouth disease vaccines in cattle

Abstract

Seroconversion of three different commercial inactivated quadrivalent Foot-and-Mouth disease vaccines were studied. One aluminium hydroxide gel vaccine and two oil-adjuvanted vaccines were used for the study in three groups of cattle. Monthly assessment of antibody titres against 0, A, C and Asia-I antigens were made by liquid phase blocking-ELlS A (LPB-ELISA). Unvaccinated calves of four months and above age were grouped into three and vaccinations were made as per manufacturer's regime. Group I and group Il animals did not showed significant difference in type ° antibody titres throughout the study period except following booster vaccination of group I in seventh month. Both groups maintained protective titres except in the fourth and fifth months of study. Group III showed a lower level of antibody titres throughout the study period. Protective typeA antibody titres were maintained by group I and group H animals during the entire study period except in the fifth month. No significant difference between these two groups observed except following the second booster vaccination in group H. Group III showed comparatively lower antibody titres against type A FMD antigen. All the three groups showed protective mean type C antibody titres throughout the study period. But group III showed an antibody titre below protective level during fourth month. Group I and group II did not show significant variation in antibody titres except following respective booster vaccinations. Group I and group II maintained a protective level of type Asia-l antibody titres except during fifth month. Group III showed significantly low Asia-l antibody titres throughout the study period. The booster vaccinations produced anamnestic response in group I and group Il in almost all cases. Group III animals showed lower antibody titres against all the four virus types when compared to group I and group Il and response to booster vaccinations were poor in group Ill. Comparison between the three vaccines in terms of cost required for immunising a single animal for the first one year revealed that oil-adjuvanted vaccine Il required the lowest cost while oil-adjuvanted vaccine III required the highest cost for the first one year.