Occurrence and molecular detection of BoHV-1 among farm animals

Abstract

Bovine herpes virus type 1 (BoHV-1) is an economically important, worldwide distributed pathogen of domestic and wild Bovidae. It causes respiratory tract manifestations and/or abortion. The present study was achieved to study seroprevalence and isolate BoHV-1 from suspected cattle, buffaloes, sheep and goats collected from three governorates in Egypt (Menofya, Kalubeya and Dakahlia) during the years 2017 and 2018. Serum and milk samples obtained from apparently healthy non-vaccinated animals were tested for detection of BoHV-1 specific antibodies by indirect ELISA method. A total of 78 (22.5%) serum samples and 46 (13.3%) milk samples out of 346 and 300 samples, respectively, were positive. Virus was isolated from nasal swabs and lung tissue samples on chorio-allantoic membrane (CAM) of 11-day-old specific pathogen free embryonated chicken eggs. It showed pin-point small foci, scattered on CAM membrane. Examination by electron microscope using positive staining methods showed the characteristic morphology of the herpes virion (an enveloped virus with 120 to 200 nm diameter). The viral isolate was confirmed to be BoHV-1 in a PCR assay using specific primers produced a fragment (575 bp) of gC encoding gene in the viral DNA genome.