Seminal transmission of lumpy skin disease virus in heifers

It is known that lumpy skin disease virus (LSDV) can be shed in bull semen following infection and also that artificial insemination (AI) poses a biosecurity risk. However, it is not known whether the use of LSDV infected semen in AI poses a biosecurity risk. The aim of this study was to investigate whether LSDV, transmitted through semen, can infect cows and their embryos. Two controlled trials were performed simultaneously. Eleven young beef heifers, naïve to LSDV, were synchronized using an OvSynch protocol and inseminated on Day 0 with fresh semen spiked with a field strain of LSDV on day 0. Six of the heifers were superovulated on Day 1 using pregnant mare serum gonadotropin, and embryos were flushed from these heifers on Day 6. Blood and serum samples were collected from Day 4 until Day 27 to determine the presence of LSDV by PCR and virus isolation, and the presence of antibodies against LSDV by SNT. The first clinical signs of LSD were noticed on Day 10, followed by severe generalized LSD in three heifers and mild LSD in two more heifers. Two heifers were humanely euthanized due to severe unresponsive stranguria. LSDV was detected by PCR, virus isolation or electron microscopy in blood, embryos and organs of experimentally infected animals; and eight heifers had seroconverted by Day 27. Two control animals were not affected. This is the first report of experimental seminal transmission of LSDV in cattle.