Demonstration of porcine circovirus type 2 in the testes and accessory sex glands of a boar

Abstract

Porcine circovirus type 2 (PCV2) antigen was demonstrated in lungs, lymphoid tissues, intestines, and testes and accessory sex glands of an 11-month-old boar from a boar stud with a history of recent illness and infertility. At necropsy, the lungs failed to collapse and there was moderate cranioventral bronchopneumonia. Microscopically, there was severe multifocal suppurative and histiocytic bronchointerstitial pneumonia with severe peribronchiolar lymphoid hyperplasia. Mycoplasma hyopneumoniae nucleic acids were demonstrated in lung by polymerase chain reaction (PCR), and moderate numbers of Pasteurella multocida type D were isolated from the lungs. There was mild to moderate lymphoid depletion and histiocytic replacement of follicles in lymphoid tissues associated with PCV2 antigen. Immunohistochemistry revealed PCV2-specific staining in the cytoplasm of macrophages and fibroblast-like cells in the interstitium of the seminal vesicles, and PCV2 nucleic acids were demonstrated in semen by nested PCR. These findings suggest that PCV2 was part of the disease complex that contributed to the illness in this boar.