Aquafeeds
A recent study evaluated the effects of a fishmeal-free diet on Atlantic salmon performance and fillet quality during successful growout to market-size in a commercial-scale, land-based, closed-containment system using water recirculation technology. Test fish performed well, with 97 percent survival during the 10-month growout period.
Health & Welfare
To evaluate the application of an air pressure-based transport method within a recirculating aquaculture system, the authors performed testing with harvest-size salmon at The Conservation Fund Freshwater Institute.
Health & Welfare
The use of larger and deeper tanks can reduce building, labor and other aquaculture production costs. However, the ability to grade and transfer large numbers of fish is more challenging when using large tanks. In a comparison of the effectiveness of a purse seine and a hinged clamshell to crowd fish in large tanks, the latter was easier to control and less stressful to salmonids. With a slotted bar rack in a side panel of the clamshell crowder, fish were simultaneously graded in size.
Responsibility
Dozens of land-based, closed-containment salmonid RAS systems are coming on line. New projects are bringing new principles into the salmon industry. Industry expansion hinges upon the development of pollution-mitigating technologies to reduce nutrients in effluents.
Health & Welfare
The benefits realized by recirculating aquaculture systems – including enhanced fish growth, product quality and survival, as well as reduced treatment costs – have made the RAS approach an important production trend.