Pathologic Evaluation of Type 2 PorcineReproductive and Respiratory SyndromeVirus Infection at the Maternal-FetalInterface of Late Gestation Pregnant Gilts

• Author(s) / Creator(s)

  • Novakovic, Predrag
  • Harding, John C. S.
  • Al-Dissi, Ahmad
  • Ladinig, Andrea
  • Detmer, Susan E.

• The pathogenesis of fetal death caused by porcine reproductive and respiratory syndromevirus (PRRSV) remains unclear. The objective of this study was to improve our understand-ing of the pathogenesis by assessing potential relationships between specific histopatho-logical lesions and PRRSV RNA concentration in the fetuses and the maternal-fetalinterface. Pregnant gilts were inoculated with PRRSV (n = 114) or sham inoculated (n = 19)at 85±1 days of gestation. Dams and their litters were humanely euthanized and necropsied21 days later. PRRSV RNA concentration was measured by qRT-PCR in the maternal-fetalinterface and fetal thymus (n = 1391). Presence of fetal lesions was positively related toPRRSV RNA concentration in the maternal-fetal interface and fetal thymus (P<0.05 forboth), but not to the distribution or severity of vasculitis, or the severity of endometrial inflam-mation. The presence of fetal and umbilical lesions was associated with greater odds ofmeconium staining (P<0.05 for both). The distribution and severity of vasculitis in endome-trium were not significantly related to PRRSV RNA concentration in maternal-fetal interfaceor fetal thymus. Endometrial inflammation severity was positively related to distribution andseverity of vasculitis in endometrium (P<0.001 for both). Conclusions from this study sug-gest that type 2 PRRSV infection in pregnant gilts induces significant histopathologicallesions at maternal-fetal interface, but they are not associated with presence of PRRSV inthe maternal-fetal interface at 21 days post infection. Conversely, fetal pathological lesionsare associated with presence of PRRSV in the maternal-fetal interface and fetal thymus,and meconium staining is significantly associated with the presence of both fetal and umbili-cal lesions observed 21 days post infection.

• Date created

  2016-03-10

• Subjects / Keywords

  • Porcine Reproductive and Respiratory Syndrome
  • Sows
  • Pregnancy in mammals
  • Swine
  • Fetal death
  • Histopathy
  • Diagnosis
  • Diseases
  • Anatomy
  • Autoimmune diseases
  • Biology and life sciences
  • Blood vessels
  • Cardiovascular anatomy
  • Clinical immunology
  • Clinical medicine
  • Developmental biology
  • Embryology
  • Endometrium
  • Fetuses
  • Immune response
  • Immune system
  • Immunology
  • Inflammation
  • Inflammatory diseases
  • Maternal health
  • Medicine in health sciences
  • Obstetrics and gynecology
  • Pathology and laboratory medicine
  • Pregnancy
  • Reproductive system
  • Research article
  • Rheumatology
  • Signs and symptoms
  • Thymus
  • Uterus
  • Vasculitis
  • Women's health

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/r3-tvm4-2g57

• License

  Attribution-NonCommercial 4.0 International