Account of an outbreak of malignant catarrhal fever in Murrah buffaloes in the Minas Gerais state, Brazil

An outbreak of Malignant Catarrhal Fever (MCF) resulting in death of 5 buffaloes in the same farm. Four buffaloes died 10-15 days after the beginning of the signals and the another one was euthanized in extremus, after similar signals. Histopathological examination showed lesions suggestive to MCF in buffaloes such as epicarditis and multifocal miocarditis with infiltrates of mononuclear lymphocytes and macrophages besides lymphocytic interstitial pneumonia. PCR revealed 98% homology between an amplified fragment obtained from the CNS of the buffaloes and specific sequences of OHV-2. Diagnosis of MCF was firmed in epidemiological, clinical, gross and histopathological findings and in results of a semi-nested PCR.