[Specific immunoprophylaxis trials with calves against foot-and-mouth disease].

Studies were conducted on vaccination of different age groups of calves with monovalent and biovalent vaccine against foot-and-mouth disease using various immunization patterns. The studies showed that passive immunity of calves impedes the building up of solid immunity. It is recommended on the basis of comparative studies of different immunization schemes to vaccinate calves under 6 months of age with double vaccine dose and to revaccinate them 1--2 months later. It was shown that calves aged 6 to 12 months react to vaccine against foot-and-mouth disease as adult animals but revaccination is also recommended to build up solid immunity. The influence is discussed of various factors hindering the building up of solid post vaccination immunity in young animals following vaccination with vaccine against foot-and-mouth disease.