A PILOT PROJECT FOR THE ERADICATION OF AU JESZKYS-DISEASE (PSEUDORABIES) IN PIGS BY MEANS OF VACCINATION .2. SEROLOGICAL INVESTIGATIONS INTO THE LATENT INFECTION IN FATTENING PIGS

The aim of the study was to prove in a region in the North-West of Ger many that there is the possibility to decrease the prevalence of laten t Aujeszky's Disease infections by means of a systematic vaccination. For this, the most important precondition of the success in a high pop ulation immunity that is maintained also in the finishing pig until sl aughter. Since it is known that maternal antibodies interfere with the active immunization in the prefattening period, procedures were to be found that guarantee a high immunity in spite of the colostral antibo dies. The results of the study show that the existing recommendation f or vaccinating fattening pigs are sufficient for the prevalence of lat ent infections. They also confirm the necessity to carry out a check- and slaughter policy at the end of the eradication program.