A restricted feeding regime does not only improve the feed conversion factor and reduce the cost of feed; it also has a positive effect on the flesh quality. The increased muscle quality using a restrictive feeding regime is associated with a higher muscl e fibre density, and an enhanced texture and colour on the fillet. In the present project, the effect of restricted feeding regimes from the first winter in sea on the muscle quality and the underlying physiological processes will be elucidated using two different smolt groups. The trials will be run in quadruple, full size net pens, with either restrictive feeding or satiation feeding. To clarify the mechanisms behind muscle cellularity and muscle quality, and why a relatively small reduction in feeding and growth improves muscle cellularity, muscle cellularity, collagen and crosslink concentration in relation to the growth pattern will be investigated. Adding to this, endocrine regulatory factors of growth and lipid metabolism and deposition will be ana lyzed. After the salmon have reached full size and been harvested and quality graded, an economical evaluation will be made on the profit by using the different feed and feeding regimes.