Detection of bovine papillomavirus type 2 DNA in commercial frozen semen of bulls (Bos taurus)

Papillomaviruses are found in epithelial lesions and are linked to different carcinogenic processes in humans and other animals. Although bovine papillomavirus (BPV) has been characterized as epitheliotropic, the presence of viral DNA has been detected in other sample types, including fresh semen. The aim of this study was to evaluate the presence of BPV DNA in spermatozoa and seminal plasma samples of commercial frozen semen taken from bulls (Bos taurus) and its effects on semen function. PCR assays were conducted with specific primers to detect BPV types 1–6 in 40 semen samples of dairy Gir bulls. The semen quality was assessed by the use of parameters such as motility, vigor, acrosomal integrity and DNA integrity. BPV-2 DNA was detected in all of the sperm cell samples and all the seminal samples; however BPV-1, 3, 4, 5 and 6 could not be detected. The presence of BPV DNA was apparently not a cause of reduced sperm function. This is the first record of BPV-2 DNA the commercial frozen semen taken from dairy Gir cattle by several companies that provide semen. Further studies are needed to assess the viability of the virus and the extent to which it can be spread through semen.