Experts look to strike the right balance for salmon gill health

A research group in Scotland is embarking on a project that could enhance fish health and wellbeing by significantly improving the global aquaculture sector’s understanding and treatment of gill disease.

The consortium – which comprises Scottish Sea Farms, Marine Scotland Science, the University of Aberdeen, BioMar, and the Scottish Aquaculture Innovation Centre (SAIC) – is exploring the geographical, temporal, and nutritional factors that affect salmon’s gill health across sites in Scotland and Tasmania, Australia.

Gill health is one of the aquaculture sector’s biggest challenges and, therefore, a major focus of research efforts. Warming seas and the progressive de-oxygenation of water, caused by climate change, are reinforcing the need for a greater understanding of the disease, along with its prevention and treatment.

Gill health is understood to be influenced by a broad set of factors – ranging from site-specific variables and fish diet, to water temperature and oxygenation levels. The consortium’s project will aim to find the optimum balance for each measure to promote good health and improve natural resistance to gill conditions among salmon. 

Supporting the Scottish Government’s 10-Year Farmed Fish Health Framework, the project will also create a set of biomarkers to monitor gill disease; develop new diagnostic tools that could minimise individual interpretation of results; and explore the production of feeds to alleviate poor gill health. 

Dr Ralph Bickerdike, head of fish health at Scottish Sea Farms, said: “The gills play a crucial role in the overall health of a fish, so the more we can learn about how best to protect these vital organs the bigger the advances we can make to further improve welfare and increase survival rates. What’s exciting about this latest collaborative research project is that it takes a holistic view, exploring not just the key factors affecting the gills but also how they might impact on one another, helping us to identify the best growing conditions for farmed fish health.”

Professor Samuel Martin from the University of Aberdeen School of Biological Sciences: “The gill is a key organ with roles in oxygen exchange but also has extremely important function for fish health.  In recent years there is a recognition that new research in gills needs carried out, particularly in marine stage salmon. This project, working directly with industry will help define how gill health varies between farm sites and at different times of the year.  The outcomes will lead to better understanding and early warning for gill health issues.” 

Caroline Griffin, aquaculture innovation manager at SAIC, added: “Gill health is among the foremost challenges facing aquaculture across all salmon-producing regions of the world. The project is about finding a way of using the vast amounts of data collected to create the right balance of conditions for salmon, enhancing their resilience. On top of that, the development of biomarkers and new feeds could act as a significant boost to fish health and wellbeing, and our overall understanding of this complex disease.”

The project is about finding a way of using the vast amounts of data collected to create the right balance of conditions for salmon, enhancing their resilience.

Caroline Griffin, Aquaculture Innovation Manager, SAIC

More project details here