The Novel Tools for Salmon Health Management module, supported by the Ocean Frontier Institute (OFI), recently organized a workshop in Nova Scotia to share new modelling tools with industry, governmental, and academic stakeholders.
Led by Dr. Ian Gardner, the Canada Excellence Research Chair (CERC) laureate in Aquatic Epidemiology at the University of Prince Edward Island (UPEI), one of the goals of the module was to develop computer models to simulate the spread of viral, bacterial, and parasitic diseases (including sea lice) in marine-farmed Atlantic salmon, following a theoretical introduction of infection into a farm site.
.jpg)
OFI funded the initial stage of the research, which focused on the development and validation of a waterborne spread model (called Hydroepix) that was applied to salmon health management in Newfoundland and British Columbia. Dr. João Romero, a former PhD student at UPEI and a key researcher in the project, provided an overview of this work describing how the model can be used to strengthen health management practices on salmon farms. Disease risk information can be used in conjunction with ocean circulation models to better understand spread of infectious agents in seawater. Modeling results can be used to help reduce the risk of disease in farmed populations and exposure to wild salmonids near farms.
“Infectious disease modeling provides a simplistic representation of the workings and logic of a real biological system,” said Dr. Romero. “This modeling approach can be used to quantify characteristics of potential disease outbreaks, and evaluate the effectiveness of control strategies, thus providing a useful tool for decision makers.”
.jpg)
To estimate model parameter values, users can integrate information from experimental studies, previous disease outbreaks, or by consulting experts. The model can then be used to simulate various infection scenarios including spread within an aquaculture net-pen, between net-pens in the same lease, and between different leases. In addition, the model can simulate various control strategies (e.g., vaccination, enhanced surveillances and diagnostic testing, and depopulation of fish in positive net-pens) to determine those that are most effective.
During the second stage of the research, Fisheries and Oceans Canada, the Centre for Marine Applied Research, and Nova Scotia’s Department of Fisheries and Aquaculture provided support for the development of a web-based, user-friendly, R Shiny app that can be used to run simulations of the Hydroepix model to assess infection risk in fish. The workshop was an opportunity for interest holders to provide feedback on the R Shiny app and suggest improvements to help potential users understand the results. Hydroepix is intended to be used by aquatic animal veterinarians, fish health specialists and decision makers in Canada and ultimately, on a global scale. The model can be adapted to diseases of other fish species as well as to oyster diseases.
“OFI funded the initial modeling research for several PhD and post-doctoral students and this was an important steppingstone for many of those people,” says Dr. Gardner. One of those researchers is Dr. João Romero, who has recently started an Assistant Professor position in Portugal, where he plans to continue his career in aquatic animal health management and disease modeling.
