The loss of fish in the seawater (SW) phase of Atlantic salmon farming is high, and a major proportion of this loss occurs in the period just after SW transfer. In the current study, we hypothesize that improvements made to the diet during the freshwater (FW) stage affect fish growth, survival and robustness later in the SW stage. To test this, salmon parr were fed five experimental diets in FW at 12 °C. In addition to a commercial-like control diet, fish were fed a diet with changed FA composition aimed to be more like the natural feed of salmon in FW, a diet with increased concentrations of selected AA/N-compounds (methionine, lysine, threonine and taurine), a diet with increased concentrations of methionine and certain B-vitamins (folate, B₁₂ and B₆) and a final diet combining all of these potential improvements. At the time of SW transfer, the robustness of fish fed the different diets was tested by direct transfer to SW at three different temperatures (8, 12 and 16 °C, without prior acclimation), as well as transfer into open net pens, while fed on a common commercial diet. Growth and proximate composition of the fish did not differ between the diet groups. All diet groups seemed to handle transfer to SW well, and while SW transfer elicited a stress response in the fish, this was not significantly different between diet groups. Fish transferred to SW at 8 °C had higher mortality, reduced mucus layer and increased prevalence of scale loss and wounds, but this applied to all diet groups. Hence, direct transfer to SW at a lower temperature than the fish has been acclimated to cannot be recommended. At the two highest temperatures, there were some differences between the groups in the severity of cataracts. Apart from this, none of the health- or welfare related parameters measured showed any difference between the diet groups, indicating that the control diet was already sufficient.

在大西洋鲑鱼养殖的海水（SW）阶段，鱼类的损失很高，这种损失的很大一部分发生在SW转移之后的时期。在当前的研究中，我们假设淡水（FW）阶段对饮食的改善会影响西南阶段后期鱼类的生长，存活和健壮性。为了对此进行测试，在12°C的鲑鱼皮中喂了五种实验性饲料。除了商业化的对照饮食外，还给鱼类饲喂了FA组成发生变化的饮食，目的是使其更像FW中的鲑鱼的天然饲料，即增加了选定的AA / N化合物（蛋氨酸，赖氨酸，苏氨酸）浓度的饮食和牛磺酸），增加蛋氨酸和某些B-维生素（叶酸，B ₁₂和B _6的浓度）的饮食）和结合所有这些潜在改进的最终饮食。在SW转移时，通过在三种不同温度（8、12和16°C，无需事先适应）下直接转移到SW以及转移到开放式网箱中来测试饲喂不同日粮的鱼的健壮性。以普通的商业饮食为食。饮食组之间鱼的生长和附近成分没有差异。所有饮食组似乎都很好地处理了向SW的转移，尽管SW转移引起了鱼的应激反应，但饮食组之间没有显着差异。在8°C时转移至SW的鱼死亡率更高，粘液层减少，水垢损失和伤口的患病率增加，但这适用于所有饮食组。因此，不建议直接在比鱼类适应的温度低的温度下将其直接转移至西南。在两个最高温度下，两组之间白内障的严重程度有所不同。除此之外，所测量的与健康或福利相关的参数均未显示饮食组之间有任何差异，表明对照饮食已经足够。