Search

Porcine circovirus type 2 (PCV2) and swine influenza virus (SIV) are important pathogens for porcine respiratory disease complex, which is economically significant worldwide. The pathogenesis of PCV2-SIV coinfection is unknown. In this study, we focused on establishing a challenge model for PCV2 to determine whether SIV influences PCV2 replication and increases the severity of PCV2-associated disease. Cesarean-derived colostrum-deprived pigs were inoculated intratracheally with cell culture medium only (negative control group), PCV2 only, or PCV2 followed 1 wk later with SIV H1N1. Two pigs from each group were necropsied at 12, 21, 28, and 35 d after inoculation. Coinfection with SIV did not increase the number of PCV2 genomic copies in serum or target tissues or the severity of microscopic lesions associated with PCV2 in lung or lymph node. The antibody titer to PCV2 did not differ significantly between PCV2-SIV- and PCV2-infected groups. In conclusion, SIV H1N1 did not influence PCV2 replication in dually infected pigs in this study.

The article shows the function of Bovine viral diarrhea virus (BVDV) in progression of Porcine circovirus-2 (PCV-2). Two studies were performed, where the first one involved vaccination of germ-free pigs vaccinated with different PCV-2 and BVDV viruses. The second study looked at cesarian-derived, colostrum-derived pigs that were vaccinated with the viruses. Results showed that BVDV and PCV-2 hinder growth and caused death of pigs through developing acute respiratory distress.