Ovine herpesvirus type 2 infection in captive bison in India

Abstract

Malignant catarrhal fever (MCF) is a lymphoproliferative multisystemic fatal syndrome of many domestic and wild animals. The present study was conducted on animals of different species (cattle, buffalos and sheep). The clinical examination revealed high persistent fever, corneal opacity, mucoprulent oronasal discharges, mucosal lesions and ulcerative skin lesions. Examined sheep showed no clinical signs. Peripheral blood leukocytic (pb1) samples were collected for laboratory investigations. Semi nested polymerase chain reaction (PCR) assay have been used. Sequencing and phylogenetic analysis were performed for the positive PCR products. Positive staining electron microscopy (EM) and histopathology were also performed. Ovine herpesvirus 2 (OvHV-2) DNA was detected in PBL of 25 animals (12 cattle, 2 buffaloes and 11 sheep). The phylogenetic analysis of the OvHV-2 PCR products revealed 100% identity with the OvHV-2 strains of Brazil, USA and India. The positive staining EM detected herpesviral particles. The histopathological examination showed pansystemic vasculitis with lymphocytic infiltration in lymphoid and non lymphoid organs.