Rabies in pigs: Clinical report and diagnostic challenges

This paper reports the occurrence of swine rabies in Brazil and discusses the difficulties of clinical and laboratory diagnosis in this species. Two pigs from different farms, were diagnosed with rabies and were raised where cattle had previously died from the disease. Affected pigs had hindlimb paralysis, lateral recumbency, and paddling movements. Histological examination of the brain revealed lymphoplasmacytic encephalitis, although intracytoplasmic inclusions were lacking. Immunohistochemistry revealed intense staining of rabies antigen in brainstem neurons, moderate immunoreactivity was observed in the cerebrum, and was absent in the cerebellum. Immunohistochemistry was effective in the definitive diagnosis of rabies encephalitis in swine.