Comparative pathology of piglets natually infected with high-pathogenic PRRSV and artificially infected with American strain PRRSV (VR-2332).

The article examines the pathological characters and pathogenesis of piglets naturally infected with high-pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) and artificially infected by American strain. It is intended to find the pathogenic traits of the virus. The typical pathological changes are cyanosis of feet and flecked bleeding in skin. The tissue pathological change in natural cases include necrosis of lymphoid tissues and viral encephalitis.