Transporting salmon without infections or lice

In the future, aquaculture will have adapt to stringent standards of hygiene and infection control, say researchers, so they have developed a well-boat concept packed with technology that will lead to more environmentally friendly operation and better-quality fish.

Well-boats are used to transport live fish in modern fish-farming, both out to the sea-cages and from the cages to the slaughterhouse. The problem is that at present, these boats release water from thetanks that the fish swim inas the are being carried. This means that diseases and parasites such as lice can be spread with the water, explains researcher Mats A Heide.

Heide is a research scientist at SINTEF Fisheries and Aquaculture -- and the man who designed the technology-heavy innovation.

Cooperation with industry participants

The researchers developed the concept in cooperation with industry participants in the course of the project "Development of the future well-boat technology," supported by the Research Council of Norway

Early in the project it became clear that it would be essential to improve hygiene and control of infection compared to current boats. In order to obtain inspiration for good hygiene solutions the researchers visited Tine Dairies, and other requirements for food production hygiene provided guidelines for their design choices.

The newly developed well-boat concept is packed with innovative technology that will ensure easy cleaning and prevent releases of potentially infectious water from the wells.

High-tech hygiene

The new well-boat concept is designed around the wells or cargo tanks, and pays particular attention to hygiene-friendly design. For example, tanks have been designed with rounded corners to ensure that automatic cleaning systems reach all surfaces -- important for preventing biological material from building up.

The vessel is also equipped with a system that circulates fresh seawater within the tank. This keeps the water quality high, so that the fish do well during their journey.

Prevents spread of infection

Filter systems enable the waste-water to be cleaned before it is discharged, or the water can be recycled after treatment, which allows the boat to go for long periods without discharging water. In practice this means that fish can be carried with a much higher safety margin against the spread of infection.

Another device that will also prevent the spread of infection is a closed drainage system that can transfer fish into and out of the boat without water exchange in the well. This solution significantly reduces the risk of infection especially at slaughterhouses, although Norwegian slaughterhouses are not adapted yet to a system of operation which allows this technology to be used to the full.

"Delousing shower"

The researchers also want to give the fish special treatment: an automatic cleaning system removes the lice that are attached to the fish when they are brought on board. This "delousing shower" removes the lice and collects them without the use of chemicals.

Reduced energy consumption

Solutions have also been developed that offer more freedom in the design of the well, in turn leading to greater freedom to improve the design of hulls less resistance, which helps to reduce energy consumption

The regulatory challenge

"We believe that Norwegian regulations regarding hygiene and infection control are inadequate, while there is also a lack of knowledge about how diseases are spread. Some technology for control of infection does already exist, but we see a need for further requirements and regulations for this to be adopted.

"Current regulations primarily apply to systems and areas where outbreaks of disease have already occurred. We therefore expect that in the future, regulations will be much stricter, and believe that our well-boat concept will be a good answer to the demands that the industry will face in the future," says Heath.

The project has been a user-guided innovation project, financially supported by the Research Council of Norway, and involved collaboration between SINTEF Fisheries and Aquaculture, Cflow Fish Handling, Flatsetsund Engineering, the National Veterinary Institute, Rolls-Royce Marine, Silver Trans Shipowners and Marine Harvest Norway.