Molecular detection and characterization of ovine herpesvirus-2 using heminested PCR in Pakistan

• Published in: Journal of veterinary science (Suwŏn-si, Korea) Vol. 22; no. 4; p. 51.1
• Main Authors: Riaz, Aayesha, Dry, Inga, Dalziel, Robert, Rehman, Saif Ur, Shah, Muhammad Ali, Akhtar, Hafiz Muhammad Naeem, Yousaf, Arfan, Baig, Ruqia
• Format: Journal Article
• Language: Korean
• Published: 2021
• Subjects: Pakistan; DNA Viruses; Malignant catarrhal fever; Nested Polymerase Chain Reaction; Ruminants
• ISSN: 1229-845X; 1976-555X

Background: Malignant catarrhal fever (MCF) is a highly fatal lymphoproliferative disease of cattle, deer, bison, water buffalo, and pigs caused by the gamma-herpesviruses alcelaphine herpesvirus-1 (AlHV-1) and ovine herpesvirus-2 (OvHV-2). Objectives: This study aimed to determine the prevalence of OvHV-2 in sheep, goats, cattle, and buffalo in Rawalpindi and Islamabad, Pakistan, by applying molecular and phylogenetic methods. Methods: Blood samples were aspirated from sheep (n = 54), goat (n = 50), cattle (n = 46) and buffalo (n= 50) at a slaughterhouse and several farms. The samples were subjected to heminested polymerase chain reaction (PCR), followed by sequencing and phylogenetic analysis of the OvHV-2 POL gene and the OvHV-2 ORF75 tegument protein gene. Results: The highest percentage of MCF positive samples was in sheep (13%), whereas goat, cattle, and buffalo had lower positive percentages, 11%, 9%, and 6.5%, respectively. Four OvHV-2-positive PCR products obtained from sheep samples were sequenced. The sequences obtained were submitted to the NCBI GenBank database (MK852173 for the POL gene; MK840962, MK852171, and MK852172 for the ORF75 tegument protein gene). Phylogenetic analysis revealed a close similarity of study sequences with those of worldwide samples. Conclusions: This study is the first cross-sectional study on the prevalence and molecular detection of OvHV-2 in apparently healthy cattle and buffalo that could be carrying OvHV-2 acquired from OvHV-2-positive sheep and goats. The results indicate that OvHV-2 is circulating in Pakistan. Further studies are needed to characterize OvHV-2 and elucidate further its prevalence.