Researchers developing PCR test for oyster diseases

Aquaculture researchers in Scotland are developing a PCR method that will help detect the presence of a range of diseases and biofouling species affecting oysters and mussels, in a project that could be a significant boost to the health and wellbeing of the shellfish.

With nearly £200,000 of funding from the Seafood Innovation Fund and the Sustainable Aquaculture Innovation Centre (SAIC), the University of Edinburgh’s Roslin Institute will build a validated testing system that allows oyster growers to proactively test for Bonamia ostreae – a common and potentially fatal disease that is otherwise difficult to detect.

The 15-month project will also receive support from companies and organisations across the oyster farming and research sectors, as well as from practitioners looking to restore the shellfish to their native habitats. This includes the Association of Scottish Shellfish Growers (ASSG), the trade body for commercial shellfish cultivation; the University of Stirling’s Institute of Aquaculture; and rewilding organisations such as Blue Marine Foundation.

 Once present on a site, Bonamia ostreae cannot be eliminated and, historically, it has only been diagnosable after infection has occurred. Access to a rapid, cheap, pre-emptive test will help farmers to make more informed decisions on whether to move oysters to different locations, helping to prevent the spread of the disease.

Designed to be affordable and easy to use for growers, the testing system will also detect the presence of oyster herpes virus and vibrio bacteria, along with biofouling species such as tube worms. It builds on a feasibility study conducted earlier this year, which successfully delivered a proof of concept.

Dr Tim Bean, career track fellow at the Roslin Institute, said: “Our project will tip the way we currently diagnose diseases that affect oysters on its head – taking a pre-emptive rather than reactive approach. We are bringing together the right technology with the right people to solve some of the shellfish sector’s biggest health challenges and potentially make significant improvements to oyster health.

“This rapid, cheap and simple process will allow farmers and restoration practitioners to make more informed decisions about whether to move animals, optimising biofouling treatments and site selection. Shellfish growers are often smaller businesses, which makes it all the more important the testing equipment is readily available, easy to use, and affordable.”

Dr Nick Lake, CEO of the Association of Scottish Shellfish Growers, commented: “The development and use of a proactive testing system will benefit shellfish growers tremendously. Tube worm casts, while benign in terms of mussel quality, are difficult to remove and can interfere with packaging and presentation.”

He added that improved detection methods should also help Scotland maintain its disease-free status for the oyster herpes virus.