Seroprevalence of antibodies to porcine reproductive and respiratory syndrome virus (PRRSV) in Lithuanian pigs and wild boars

Abstract

lntroduction - Since domestic pigs and wild boars have the same susceptibility to various infections there was major concern to monitor the epidemiological pRRSV situation in Lithuanian pigs and wild boars. Therefore, the objective of the present study was to investigate prevalence and distribution of PRRSV antibodies in selected Lithuanian pig farms and in wild boars. Material and Methods - A total of 17819 pig serum samples from 33 districts and total 659 wild boars serum samples from 42 locations throughout Lithuania were collected in 2006-2011. The pig and wild boars sera were analyzed via different producers ELISA test systems (lDEXX, lngezim) according to manufacturer's instructions and in the ISO/IEC L7O25:2005 standard accredited laboratory. Results and Conclusions - pRRSV antibodies were detected in 894 out of 17819 (5.02 %) pig serum samples' The swine farms with seropositive pigs were widely distributed in the 20 of 33 Lithuanian regions. From 659 examined wild boar sera, 43 (6.5 %\ were positive to PRRSV antibody. lnvestigation of PRRSV antibodies with different ELISA kits did not show difference in detection positive serum samples. Antibodies to pRRSV were detected in all age groups however seroprevalence was significant higher in adults. Wild boars serum samples from 31 locations of 42 investigated were seropositive for PRRSV. The present study demonstrates that majority pig farms in Lithuania were positive for antibodies to PRRSV however antibody prevalence was relatively low in comparison with situation in 1997-2001 (42.2%1. Our study has also presented serological evidence of pRRSV infection in the wild boar population in Eastern Europe. lnterestingly, in neighboring countries such as Russia or Poland PRRSV antibodies in feral pigs were not detected.