Distribution of porcine parvovirus in porcine circovirus 2-infected pigs with postweaning multisystemic wasting syndrome as shown by in-situ hybridization.

In-situ hybridization with a nonradioactive digoxigenin-labelled probe was used to study the distribution of porcine parvovirus (PPV) in formalin-fixed paraffin wax-embedded tissues from 10 porcine circovirus 2 (PCV2)-infected weaned pigs with naturally occurring postweaning multisystemic wasting syndrome (PMWS). A 226 base pair DNA fragment from a VP2 structural gene was generated by polymerase chain reaction (PCR) and used as a probe. Lymph node, spleen, thymus and tonsil were positive by PCR, demonstrating the presence of PPV DNA in the tissue samples from four of 10 pigs tested. PPV nucleic acid was also detected consistently in lymph node, spleen, thymus and tonsil by in-situ hybridization. Detection of PPV DNA from PCV2-infected pigs with PMWS suggests that PPV also plays a role in the pathogenesis of PMWS.