Aquaculture now accounts for approximately 50% of global seafood supplies and continues to grow (FAO 2020). Aquaculture occurs in all 10 provinces and 1 territory in Canada, and involves the breeding, raising and harvesting of fish, shellfish and aquatic plants. It is essentially agriculture, but in the water.
In addition to providing Canadians and consumers around the world with a significant portion of their seafood, aquaculture injects over 3 billion dollars annually into the Canadian economy, and directly generates more than 15,000 quality jobs; many of which are in rural communities. Over the past few decades, finite supplies of marine fish meal and fish oil (first-generation ingredients) have been largely replaced by terrestrial plant-based ingredients (second-generation ingredients) in farmed salmon feeds. These ingredients are now becoming costly, are generally not nutritionally complete for salmon feeds, and have their own sustainability concerns.
Researchers from the National Research Council of Canada's (NRC) Aquatic and Crop Resource Development Research Centre, in collaboration with DeNova, the Center for Aquaculture Technologies Canada and Dalhousie University are focussing on research to develop more sustainable salmon aquaculture feeds. Under the NRC's Ocean program, the initiative is part of the Sustainable Protein for Aquaculture Project to support Canada's Ocean Supercluster. It will position Atlantic Canada at the forefront of the alternative and sustainable protein sector while helping to reduce harmful greenhouse gas (GHG) emissions and contribute to the sustainable growth of Canada's ocean-based economy.
Working under water
DeNova has developed deployable technologies for the sustainable and cost-efficient production of a non-GMO, single-cell protein (SCP) meal to incorporate into aquaculture feeds. The resulting protein-rich SCP meal is generated from naturally occurring methylotrophic bacteria cultivated under scalable fermentation on industrial GHG waste emissions. This high-quality, protein-rich SCP meal has tremendous potential as a next-generation, environmentally sustainable and affordable ingredient in farmed salmon feeds.
Over the past 4 years, the aquaculture nutrition team at the NRC has conducted nutritional evaluation studies to comprehensively evaluate this particular SCP meal for its nutritional value as a novel ingredient for salmonid aquafeeds. The current project is a continuation of this nutritional evaluation.
For this study, the team formulated, produced and are evaluating experimental test diets comprised of a low fish-meal inclusion level with varying levels of dietary SCP meal to partially or completely substitute soy protein. Over the course of the 6-month feeding study with post-smolt Atlantic salmon in the seawater production phase, the aim is to evaluate the effects of these novel diet formulations on feed consumption, growth performance, nutrient utilization, general fish health, intestinal health and final product quality for the consumer. The majority of the nutritional sciences work is conducted in 2 NRC facilities located in Ketch Harbour, Nova Scotia, with external partners. These include the nutritional biochemistry analytical laboratory housed in the microalgae facility and the pilot-scale feed manufacturing laboratory in the feed production facility.
Beyond the blue horizon
"DeNova approached me over 4 years ago with the intention of applying their technologies to develop a much-needed "made-in-Canada" solution to the issue of salmon aquaculture feed sustainability," says Sean Tibbetts, Research Officer at the Aquatic and Crop Resource Development Research Centre. "Over the past several years, we have comprehensively characterized many DeNova products for their proximate composition, amino acid profile, fatty acid profile, elemental concentrations, carotenoid concentrations and in vitro protein digestibility."
Sean and his team have managed fish feeding studies to generate "species-specific" apparent digestibility coefficients for proximate nutrients and essential amino acids for DeNova products and for novel feed formulations containing their products. Furthermore, they have conducted longer-term fish feeding studies to determine if their products can be effective sources of dietary protein to replace conventional marine and terrestrial plant-based ingredients in diets for Atlantic salmon during both the pre-smolt (freshwater) and post-smolt (seawater) phases.
"Working with Sean and the NRC team has been a critical part of DeNova's growth and commercialization of our sustainable alternative protein," says Brianna Stratton, President of DeNova. "Sean's leadership, knowledge in fish nutrition, and rigorous approach to research has generated meaningful data that has supported our ability to pursue regulatory applications, engage with customers, and attract capital investment. We look forward to continuing to work with the NRC as we develop an alternative protein that will contribute to the sustainability of our planet and more environmentally sound aquaculture."
This new class of high-quality, third-generation feed ingredients can be produced locally within Canada through an approach that reduces GHG emissions. DeNova intends to build on this project with additional research trials in Atlantic salmon and other species, further supporting the product development of its novel protein ingredient, which has the potential to expand the alternative proteins market.