VACCINATION AGAINST AUJESZKYS-DISEASE - C HANGES IN ANTIBODY CONTENT OF THE BLOOD OF GILTS, THEIR COLOSTRUM AND THE BLOOD OF THEIR OFFSPRING AND THE INFLUENCE OF MATERNAL ANTIBODIES ON THE VACCINATION RESPONSEOF WEANLINGS

In two vaccination trials the influence of different vaccination sched ules of gilts on the colostral immunity of their offspring and the inf luence of maternally derived antibodies on the active formation of ant ibodies after vaccination in weanlings were tested. It could be shown, that vaccination of gilts 6 and 3 weeks prior to farrowing led to hig her blood levels of maternally derived antibodies in their offspring t han vaccination earlier during gestation or prior to mating. Correlati on between antibodylevel of sow, colostrum and offspring was good, the halflife of the antibodies was 11.3 days. Low levels of maternally de rived antibodies did not influence the active formation of antibodies after vaccination, higher levels reduced antibody-formation, but did n ot suppress it completely. Sow colostrum and blood of piglets are gene rally adequate substrates for the serologic controle of breeding units regarding Aujeszky's disease. Existing problems are mentioned. The re sults of this study are discussed concerning their importance for the eradication of Aujeszky's disease with vaccination programs.