PATHOGENESIS OF PORCINE CIRCOVIRUS - EXPERIMENTAL INFECTIONS OF COLOSTRUM DEPRIVED PIGLETS AND EXAMINATION OF PIG FETAL MATERIAL

The results of virus and antigen distribution following experimental i nfection of colostrum deprived pigs with pig circovirus (PCV) by oral/ nasal and intravenous routes are reported. PCV and antigen were detect ed using virus isolation and indirect immunofluorescence on cryostat s ections respectively. PCV antigen was detected in tissues throughout t he body but primarily in spleen thymus, and lung. No PCV antigen or vi rus was detected in tissue samples from the central nervous system. Ex amination of pig foetal material from field cases of abortion/stillbir th resulted in 3 PCV isolates from 2 sera and a spleen sample from 2 g roups of stillborn piglets from the same farm. No antibody to PCV alon e was detected in 160 foetal sera tested. These results suggest that t ransplacental infection with PCV does occur, possibly prior to foetal immunocompetance. However, it is probably not a significant cause of r eproductive disorders in pigs in Northern Ireland.