The results of Aujeszky's disease virus elimination from pig farms after 5years of implementing the "vaccination-eradication programme"

The development in the late 80-s of the deleted (marker) vaccines, which en able serological differentiation between pigs infected with Herpesvirus sui s type 1 (SHV-1) and those vaccinated with these vaccines, was the turning point Aujeszky's disease (AD) eradication. A vaccination-eradication progra mme based on deleted, mainly gE-negative, vaccines is at present intensivel y implemented in several European countries and in the United States with p lanned completion in the year 2000. The objective of the study was to evalu ate the results of SHV-1 elimination from pig farms after 5 years of implem enting the vaccination-eradication programme. The study was carried out in two highly infected pig farms R. and B. located in the north-eastern region of Poland, in which implementation of this programme was the most advanced . In the Sears 1986-1998 intensive vaccinations of all the pigs in both far ms using Porcilis Begonia vaccine (Intervet, Holland) were continued. To co ntrol the decrease of SHV-1 infection level, the serological examinations o f reproductive pigs and pigs from other age groups using gE-ELISA - Pseudor abies Virus gp I Antibody Test Kit (Herd Chek Anti-PRV gp I), IDEXX Lab. In c. USA were performed. In farm R. the study revealed a decrease of SHV-1 in fection level in reproductive pigs from 100% to 10,7% after 3.5 years of pi g vaccinations. Positive results were found in only 8 out of 72 sows, with no seropositives in boars and fatteners. In farm B. after 4.5 years of pig vaccinations and 1.5 years of culling SHV -1 infected reproductive pigs, only 3 doubtful results (1 boar, 2 sows) out of 1714 sows and gilts and 38 boars were found. There mere no seropositive s among piglets and fatteners. Farm B. is the first pig farm in Poland in w hich SHV-1 was eliminated using,,vaccination-eradication programme" for abo ut 5 years (62 months), It is proof that this programme can be effective in SHV-1 elimination even in very large and highly infected pig farms.