SecureFeed

The SecureFeed project will provide knowledge about and document the level of biosecurity when using organic material from salmon farming waste to produce safe feed ingredients for terrestrial and marine organisms.

Low-trophic organisms, such as black soldier flies and bristle worms, are able to use aquaculture sludge as a growth medium and convert it into animal protein that can be used for fish and animal feed. There are gaps in our knowledge about the ability of such organisms to alter and transmit risk factors, such as infectious agents and heavy metals that may be present in the growth medium. Large quantities of aquaculture sludge are produced in Norway, and it is essential to learn more about this in order to continue on the path towards a more circular bioeconomy. In addition to sludge from recirculation aquaculture systems (RAS), larger volumes of sludge from closed sea farms can be expected in the future. Identifying risk factors associated with the use of sludge as a growth medium for the production of low-trophic animal protein is a step towards the future local use of aquaculture sludge. Management and industry depend on a secure knowledge base for assessing the use of this resource.

Sludge currently represents primarily a cost for salmon producers and provides limited value for the industry and society at large. This is because knowledge is mainly limited to biosafety related to the use of sludge as a low‑cost input for biogas production and as fertilizer in agriculture. Major logistical challenges and the properties of wet sludge make further utilization difficult.

The project addresses this lack of knowledge and may have two different outcomes:

  1. Sludge cannot be safely used as feed for low‑trophic animals.
  2. Sludge can be safely used as a feed input for low‑trophic animal production.
    Current regulations are adequate and correctly address the issue.

This will lead to:
a) The current regulations on the use of sludge as feed must be revised, as there is no scientific basis for them.
b) The field opens up for multiple business opportunities.
c) A massive increase in the sustainability of the aquaculture industry can be achieved.

First and foremost, the 200,000 tonnes of sludge currently produced annually would immediately shift from being an environmental problem to a resource. Regarding business opportunities, Norwegian insect production is constrained by feed availability. If sludge from salmon farming can serve this purpose, the aquaculture industry takes a quantum leap in the development of sustainable insect production. In addition to insects, a ragworm industry could be established to supply the fish feed market, but also to be sold as bait and shrimp‑maturation feed, with market prices around NOK 200 per kg of fresh worms, depending on the market.

The following will be carried out:

  • Publish a critical literature review of relevant scientific publications, map upstream and downstream collection and treatment of sludge, and assess the feed industry’s requirements for using sludge as a feed ingredient.
  • Conduct controlled inoculation (“spiking”) experiments with a selection of pathogens based on collected and systematized knowledge, and measure the transfer of potentially toxic elements in the model organisms ragworm and black soldier fly larvae after growth on a sludge‑based substrate.
  • Identify and document possible measures to ensure safe (biosecure) use of sludge from salmon farming as a growth substrate for low‑trophic organisms that may be used as feed raw materials for terrestrial and/or marine species.

Publications

The project is a collaboration between SINTEF, the Institute of Marine Research, and the Norwegian Veterinary Institute, and is funded by the Norwegian Seafood Research Fund (FHF).

Project period: 2022–2023