Aquaculture is growing to meet the increasing demand for aquaculture products but is not free of environmental impacts. One solution is to improve how feed are formulated, limiting the environmental impact of fish production. Multiobjective (MO) formulation, which aims for a compromise between lower cost and lower environmental impacts, appears to be a promising solution to reduce the environmental footprint of aquaculture production. The objectives of this study were to design an eco-friendly trout feed (ECO-diet) using MO formulation and to compare its zootechnical and environmental performances to those of a commercial feed (C-diet) containing 16% fishmeal and 6.5% fish oil. MO formulation changed the composition of the diet greatly, which decreased environmental impacts of the feed as well as its price. It increased the number of ingredients used but reduced the use of fishmeal and fish oil by half. MO formulation also led to the elimination of soy products, faba bean, and gluten in favour of processed animal co-products that have high protein contents and low climate change impact. Rapeseed oil also disappeared from the ECO-diet due to its major contribution to land use, eutrophication, and acidification and, to a lesser extent, climate change. Overall, the ECO-diet had high digestibility, which differed little from that of the C-diet. Mean fish body weight after 12 weeks of growth did not differ significantly from that obtained with the C-diet, but analysis of fish growth curves indicated that the ECO-diet could lead to lower growth in the long term. This observation was consistent with the significantly lower feed intake in fish fed the ECO-diet. The decrease in impacts observed at the feed level was also observed at the farm level, although less so for eutrophication, non-renewable energy use, and climate change calculated per kg of body weight gain. MO formulation is a useful tool to reduce the environmental footprint of aquaculture production without compromising animal performances or necessarily increasing production cost.

水产养殖正在发展以满足对水产养殖产品日益增长的需求，但并非没有环境影响。一种解决方案是改进饲料的配方，限制鱼类生产对环境的影响。旨在降低成本和降低环境影响之间折衷的多目标 (MO) 配方似乎是减少水产养殖生产的环境足迹的有前景的解决方案。本研究的目的是设计一种使用 MO 配方的环保鳟鱼饲料（ECO-diet），并将其动物技术和环境性能与含有 16% 鱼粉和 6.5% 鱼油的商业饲料（C-diet）进行比较. MO 配方极大地改变了日粮的组成，从而降低了饲料对环境的影响及其价格。它增加了使用的成分数量，但将鱼粉和鱼油的使用量减少了一半。MO 配方还导致消除豆制品、蚕豆和面筋，转而采用蛋白质含量高、气候变化影响低的加工动物副产品。由于菜籽油对土地利用、富营养化和酸化以及在较小程度上对气候变化的影响，菜籽油也从 ECO 饮食中消失了。总体而言，ECO 饮食具有较高的消化率，与 C 饮食差别不大。生长 12 周后的平均鱼体重与使用 C 饮食获得的体重没有显着差异，但对鱼类生长曲线的分析表明，从长远来看，ECO 饮食可能导致较低的生长。这一观察结果与饲喂 ECO 饮食的鱼的采食量显着降低一致。在饲料水平上观察到的影响减少也在农场水平上观察到，尽管对于每公斤体重增加计算的富营养化、不可再生能源使用和气候变化的影响较小。MO 配方是减少水产养殖生产环境足迹的有用工具，而不会影响动物性能或必然增加生产成本。