African Swine Fever virus (ASFv) is capable of transmitting in boar semen, via the route of artificial insemination (AI) to gilts and embryonic piglets. That was the outcome of joint German-US research.
The study was published late 2022 in the peer-reviewed scientific title Pathogens. Researchers from the German Friedrich-Loeffler-Institut teamed up with animal health scientists in Germany and the United States to figure out whether or not AI could be a method of transmission of the virus.
That is the case, they concluded. The virus can “efficiently be transferred from infected boars to naïve recipient gilts through AI.” In the scientific article, the team warned that therefore an infected boar stud presents the risk of rapidly and widely distributing ASFv within or between countries.
The researchers used the ASFv strain “Estonia 2014” for their trial. This was conducted at the high-containment facilities at the FLI in Insel Riems, Germany. They inoculated 4 boars (2 Large White boars and 2 Piétrain boars) intramuscularly. After this. blood and semen were collected every day. The virus’ genomes were detected in the semen as early as 2 days post-infection, in blood at 1 day post-infection while semen quality remained largely unaffected.
In addition, also 14 Large White gilts were included in the trial. After insemination with extended semen, 7 of 14 gilts were ASFv positive by 7 days post-insemination, and all gilts were ASFv-positive by 35 days post-insemination.
Twelve out of 13 gilts aborted at the onset of fever. A proportion of foetuses originating from the remaining gilt showed both abnormalities and replication of ASFv in foetal tissues.
The research paper was authored by Virginia Friedrichs, Eric A. Nelson, Tessa Carrau, Paul Deutschmann, Julia Sehl-Ewert, Hanna Roszyk, M. Beer and Sandra Blome, Friedrich-Loeffler-Institut, Germany; Darwin Reicks, Reicks Veterinary Research and Consulting, St Peter, MN, USA; Tobias Hasenfuss and Elisabeth Gerstenkorn, Bundes Hybrid Zucht Programm (BHZP), Dahlenburg-Ellringen, Germany; Jeffrey J. Zimmerman, Iowa State University, Ames, IA, USA; and Jane Christopher-Hennings, South Dakota State University, Brookings, SD, USA.