EN
The objective of this study was to analyze and estimate the epizootic situation of Aujeszky's disease (AD) in Wielkopolska voivodeship the biggest pig producing region of Poland in the years 2001-2005. Results of serological tests performed independently in the Regional Veterinary Diagnostic Laboratory (RVDL) in Poznañ (the capitol of Wielkopolska voivodeship) and in the Department of Swine Diseases of the National Veterinary Research Institute (NVRI) in Pu³awy are shown. A total number of 3584 pig sera from 480 pig farms were tested in RVDL Poznañ and 15 910 swine serum samples from 331 pig holdings were examined in NVRI Pu³awy. Serological monitoring studies revealed the presence of AD virus (ADV) antibodies in 9.2% and 1.54% pig sera, respectively. The higher percentage of positive serum samples detected by RVDL Poznañ than by NVRI Pu³awy was probably due to the fact that the sera tested by RVDL were taken from pigs with some health problems and that ones examined by NVRI came mostly from pigs from farms with a high health status (e.g. breeding and/or reproduction farms). On the other hand it is worth noticing that the seropositive pigs were found in 15.6% (RVDL) and 11.67% (NVRI) of the tested farms. From the results obtained it seems that the epizootic situation of AD was quite stable in the years 2001-2005, and the pig population in Wielkopolska voivodeship is not heavily infected with ADV. These findings should be taken into account before an AD eradication program will be implemented in this region of Poland.