Erhard van der Vries, R&D researcher at Royal GD, has won the European PRRS Research Award 2020. This prize is awarded annually to three European research proposals that innovatively contribute to combating the PRRS virus. The winning proposal follows up on previous award-winning research by GD (PRRS Award 2018), and its purpose is to gain better insight into the occurrence, prevention and spread of so-called chimera PRRS viruses at European pig farms. GD will use the 25 thousand euro prize money, made available by Boehringer Ingelheim, to realise the project.
PRRS is a disease caused by the Porcine Reproductive and Respiratory Syndrome virus (PRRSv). This virus results in fertility and respiratory problems in pigs, and has major economic consequences for pig farming worldwide. “Our research project mainly focuses on the spread of PRRS strains among pig farms in the Netherlands and Eastern Europe, and particularly highlights the role of recombinant PRRS virus strains,” explains lead researcher Van der Vries. “As our previous research in 2018 showed that there were virus strains circulating at farms, whose genetic material partly resembled a field strain and partly a vaccine strain.”
GD will apply the latest analysis methods (Oxford Nanopore Sequencing) to map out the genome (the complete genetic composition) of circulating PRRS viruses. Co-researcher Rianne Buter: “By studying the complete PRRS virus genome, we hope to discover how often recombinant or chimera PRRS viruses occur, and whether there are certain positions in the genome that are particularly sensitive to the occurrence of recombination.” The winning research proposal titled, PRRSV1 genetic recombination in swine herds: An emerging risk or hype, will be carried out not only by Rianne Buter and Erhard van der Vries, but also by fellow researchers Remco Dijkman and Tom Duinhof in collaboration with Tomasz Stadejek from the University of Warsaw (Poland). The prize will be officially awarded during the ‘European PRRSpective’, a conference that will be held for the fifth time next year, in Bern.
Erhard van der Vries
The importance of this research for pig farming
Genotyping (sequencing) of PRRS viruses is a method to distinguish between circulating field strains or a vaccine strain. This information can be useful for pig farmers and vets when deciding whether additional measures are required to prevent further spread of the PRRS virus at the farm and to reduce the disease burden.
At present, a small part of the PRRS virus genome is examined. Specifically, only the ORF5 part or the ORF2 through ORF7 parts (including ORF5) are taken for this analysis. While this provides sufficient information in most cases, more and more PRRS viruses are now found, which partly resemble a field strain and partly a vaccine strain. The circulation of such chimera or recombinant viruses makes it difficult to distinguish between a field strain and vaccine strain. This problem can possibly be solved by analysing a larger part of the PRRS virus genome.
The new research therefore sequences the complete PRRS virus genome. Comprehensive mapping of the genetic code of PRRS viruses gives a more reliable picture of the identity and the source of the virus found. GD can then advise pig farmers more effectively in the future, which could result in a considerable improvement of farm management with regard to the PRRS virus.