Journal of Aquaculture Research & Development

Intensification of salmonid production

International Conference on Aquaculture & Fisheries

July 20-22, 2015 Brisbane, Australia

Asbj�rn Bergheim

Posters-Accepted Abstracts: J Aquac Res Development

Abstract:

Commercial scale production of salmon and trout has only lasted for 30-40 years. Over this period, a remarkable progress took place within vital fields, such as genetics, nutrition and medicines, and not, least, a revolution regarding engineering and farm management. This presentation emphasizes intensification attempts of the production from the fry stage to harvest made possible by introduction of new technology and alternative farming regimes. In land-based farming of smolt, launching of oxygen (DO) injection has reduced the water consumption by some 75% and even further to 90% while combining oxygenation and stripping of carbon dioxide (CO2) in the tanks. Such combined water treatment is indicated ?partial recirculating aquaculture system (partial RAS)?and is at present the dominating system for smolt production in Norway. A vital contribution is development of efficient technology removing 60-90% CO2 per flow passage. Fully RAS, also including biofiltration, is rapidly expanding in most salmonid producing countries and is now representing more than half of the total smolt production in Chile. Such highly producing systems means improved sustainability in terms of strongly reduced water consumption and lower effluent loading due to particle removal and sludge utilization. The traditional transfer of smolt (50-100 g) to sea cages is gradually being replaced by production of so-called super-smolt of 500-1,000 g in land-based RAS or in closed floating cages before stocking in open cages. This extended ?smolt stage? results in a shorter production cycle, less sea lice and disease problems (e.g., infectious pancreas necrosis) and reduced discharge of feed-based wastes.