Immunohistopathology of Porcine Reproductive and Respiratory Syndrome

Abstract

Pathological studies showed moderate to severe interstitial pneumonia in 30 to 60% of 240 disessed swine autopsied in Gifu Prefecture from 1993 to 1998. The viral antigen for porcine reproductive and respiratory syndrome (PRRS) was immunohistochemically detected in 11.1 to 23.1% of animals with interstitial pneumonia. The viral antigen was detected in 21.4 to 30.8% of animals of less than 3 months of age and in 6.3 to 17.6% of animals of more than 4 months of age.