The prevalence of OvHV-2 in the smegma, nasal secretions and penile environment of rams (Ovis aries)

Abstract

Ulcerative balanoposthitis (UB) is a venereal disease which has frequently been diagnosed in sheep in South Africa (SA) since 1979, with no conclusive causative agent or treatment available. The purpose of this study was to determine whether ovine herpesvirus 2 (OvHV-2) can be used as biomarker to diagnose the early onset of UB in sheep flocks in SA. The study made use of 10 healthy Dohne Merino rams, two healthy Dorper rams, and 10 UB-affected Dorper rams. Smegma-, blood-, nasal swab- and sheath swab samples, respectively, were collected from all rams, and subjected to a single-tube hemi-nested PCR analysis to determine OvHV-2 status of all the sample types collected. The prevalence of OvHV-2 in all 22 animals was 22.75%, irrespective of breed or health status. The detection rate of OvHV-2 was 33.3% for the 10 UB-positive animals, and 16.7% for the 12 UB-negative animals. In blood, OvHV-2 had a 4.54% detection rate, 8.33% in smegma, 13.64% in nasal samples, and a 0% detection in penile swabs. This study found no significant co-occurrence of UB and OvHV-2, which indicates that OvHV-2 cannot be considered as a biomarker for the early onset of UB or a causative agent of UB.