Effect of swimming training in smolt; A Basic Study

To improve the salmon health and welfare, the Norwegian aquaculture industry has invested considerable resources in developing cost-effective protocols for the production of smelt in large scale containment systems in order to shorten the time at sea. Parallel to parallel to this development, the industry has implemented a significant upscaling of capacity, including various types of semi-enclosed plants and intensive RAS technology. However, recent experience has shown that even although the salmon are optimally smoltified, producers are experiencing increasing health and welfare problems, which also causes major financial losses. It is therefore questioned whether today's intensification has gone too far at the expense of smolt quality and welfare. In order to meet the industry's need for increased quality, it is necessary to develop new strategies to enhance overall health and robustness in the sea phase. A strategy that has been shown to yield positive effects is swim training with a more robust health and welfare indexes obtained. The semi-enclosed fish farm system, Preline ,(longitudinal stream with water velocity of 14 cm / sec) showed clear signs of increased growth, lower feed factor and reduced mortality compared with reference fish (ie no swim training). Observations also showed that swim training contributed to increased welfare, increased recruitment of white muscle and measurable improvements in fish heart health. Swim training can therefore be an important tool to ensure the production of large robust smolt with a future perspective, but also sets new requirements for today's production plants addressing our ability to control both water velocity and flow. Such facilities are now under development and two new innovative production facilities; Lerøy Seafood Group's Pipefarm and Bremnes Seashore's RAS facilities at Trovåg are included as a central part of the research infrastructure in this project. The aims of this project are: WP1; To establish new knowledge on interaction effects between water velocity (constant and interval) power), water quality, temperature and fish size on robustness, growth, feed utilization, physiological condition, stress response, immune status, circulatory capacity and resistance to salmon lice. WP2; To document the effect of swim training (Ufit) on welfare, performance and resistance to lice in large-scale salmon farming, from seed to slaughter WP 3; To summarize the results of DP1-2 in a new BMP protocol for production of salmon and disseminating results to breeders, professionals and authorities.