Abstract
Two 30-day-old puppies, a female mongrel (case 1) and a female Shetland sheepdog (case 2), which died without characteristic symptoms, were pathologically examined. Histopathologically, basophilic intranuclear inclusion bodies were present in the nuclei of the cardiac muscle, and necrosis of the cardiac muscle fibers was frequently observed in case 1. Case 2 showed myocarditis characterized by mononuclear cell infiltration and basophilic intranuclear inclusion bodies. Immunohistochemically, these inclusion bodies gave a positive reaction against antibody to feline panluekopenia virus. Ultrastructurally, the inclusion bodies were composed of spherical viral particles approximately 20 nm in diameter. From these findings, both cases were diagnosed as myocarditis due to canine parvovirus.
