Association of porcine circovirus 2 with reproductive failure in pigs: a retrospective study, 1995-1998

In order to determine if vertically transmitted porcine circovirus (PCV) ha s played a role in reproductive failure in pigs in areas of endemic infecti on, archival fixed tissues were examined by polymerase chain reaction (PCR) and immunohistochemistry. Tissues tested were from routine cases of aborti on or reproductive failure submitted between 1995 and 1998 to the diagnosti c laboratory at the Western College of Veterinary Medicine, Saskatoon. They originated from 29 high-health herds in the provinces of Alberta and Saska tchewan and comprised a total of 36 individual submissions. Porcine circovi rus type 1 (PCV1) was not detected by PCR in any submitted tissues. Porcine circovirus type 2 (PCV2) was not detected by PCR or immunohistochemistry i n any of the submitted tissue. The effect of extended formalin fixation on the detection of PCV2, by PCR was assessed and fixation for up to one week had no gross effect on sensitivity of detection using this PCR technique. F ailure to detect porcine circoviruses in cases of reproductive failure prio r to 1999 in areas of endemic infections, suggests that reproductive diseas e may be a new clinical manifestation of PCV2 infection, and that vertical transmission may not have been the primary mechanism of initial disseminati on of the virus in the pig population.