Aquaculture

The way to Weymouth

Robert Potts reports on his work with the Centre for Environment, Fisheries and Aquaculture Science.

02/06/2020 

Before lockdown was initiated in the United Kingdom, Rob—a PhD student working as part of the Roslin Institute’s aquaculture team—travelled to Weymouth to collaborate with the Centre for Environment, Fisheries, and Aquaculture Science (better known as Cefas). Group Leader Tim Bean, who has extensive experience working with Cefas, helped to organise the trip alongside Cefas molecular biologist Chantelle Hooper.

Rob’s mission to Weymouth had three essential aims:

  • Improve our Pacific oyster hatchery protocols
  • Experimentally determine a working dilution of oyster herpes virus (OsHV)
  • Accrue high-definition images and videos of Pacific oyster larvae

The second of these objectives was of particular note to Rob. “OsHV is a major threat to pacific oyster production in Europe and worldwide,” he explains. “My PhD project aims to understand the genetic basis of resistance to the disease.”

Rob worked with Chantelle Hooper to strip spawn Pacific oysters in the Weymouth labs; Cefas have an excellent system for this and have access to high quality sea water on tap, allowing Rob to assist Chantelle and the Cefas team to rear large quantities of larvae with a high survival rate (>90%) to the “d-shell” stage.

Working with Cefas staff, Rob—moving to the trip’s second objective—used the spawned larvae to test working dilutions of OsHV. Thanks to the help of Virology Team Lead Richard Paley, this was also a success, and the team used microscopes to record time-lapse videos of oysters as they were challenged by various dilutions of the disease.

Video: Oyster larvae development
Development of oyster larvae with and without OsHV over 72 hours.

Rob also received support from Pathology Team Lead John Bignell; by using a differential interference contrast (DIC) microscope to take highly detailed images and short videos of 24 hour old pacific oyster larvae. This detailed, first-hand experience of oyster development will be key to helping identify warning signs and other anomalies in future experiments and projects.

Video: Oyster larvae 24 hour development (DIC 20x)
Oyster larval development over 24 hours, as viewed with 20x differential interference microscopy.

“Visiting Cefas allowed me to better understand pacific oyster rearing and disease challenge experiments, so that we have already had very successful spawning at the Roslin institute,” Rob reports. “Working alongside Chantelle, Richard and John has given me invaluable expertise that I am already using to help progress my PhD project, which aims to better understand the genetic basis of resistance to the OsHV.”

Rob and the whole aquaculture community at Roslin wish to extend thanks to the Chantelle, Richard, John, and the wider Cefas team for sharing their resources and expertise, allowing us to conduct valuable research of our own. We are ecstatic about the success of Rob’s trip and look forward to more close collaboration with Cefas in the future.

You can access Rob's page in the People section.

A still image of an oyster larvae, one day into its development.