RESUMEN
The diagnosis of bovine herpesvirus 5 (BoHV-5) encephalitis is confirmed after death by laboratory methods applied to brain fragments. Alternative methods to confirm ante-mortem diagnosis are important because the disease is not always lethal. The aim of this study was to investigate whether the presence of the virus genome in the cerebrospinal fluid (CSF) detected by polymerase chain reaction (PCR) might be admitted as a method for ante-mortem diagnosis. CSF samples were taken from 14 animals suffering from BoHV-5 encephalitis, diagnosed by characteristic histopathological lesions in the brain and by identification of the virus genome by PCR in different portions of the brain. Virus DNA was detected in the CSF of 21.42% (3/14) of the evaluated animals. Ante-mortem detection of the virus genome in the CSF showed low sensitivity to confirm the diagnosis. The diagnosis is confirmed by a positive result but a negative one does not discard the disease.(AU)