Amoebic gill disease (AGD) is a major challenge for the marine salmonid farming industry. This disease is caused by Paramoeba perurans, which is a parasitic amoeba that affects fish growth and survival. The present work aimed at improving Atlantic salmon (Salmo salar) diet formulation as a preventive treatment for AGD. Four diets with different quantitative composition of functional ingredients, such as arginine, premixes, plant extracts, nucleotides, beta glucans, and vitamins C and E were tested. In the first trial, fish fed the different diets were exposed to a 74‐day challenge trial with P. perurans, and their survival, feed intake, and growth performance were analyzed together with plasma properties and gill histopathology. Additionally, a second trial was performed where mucus constituents of Atlantic salmon fed the same diets were analyzed from fish that were not exposed to AGD. Results suggest a positive effect of the functional ingredients on Atlantic salmon survival and immune response. Particularly, the inclusion of arginine, microadditives, and vitamins C and E improved survival, with arginine being an important driver of pathogen protection. The protective role of mucus also improved with these functional ingredients in nonchallenged fish, as suggested by its greater viscosity and by the increased levels of lysozymes and polysaccharides. Overall, the present work supports improving diet formulation as a promising approach for the preventive treatment of AGD.

中文翻译：

---

功能饮食可改善大西洋鲑（Salmo salar）对阿米巴g病的存活和生理反应

阿米巴ill病（AGD）是海洋鲑鱼养殖业的主要挑战。这种疾病是由Permoanba perurans引起的，它是一种寄生的变形虫，会影响鱼类的生长和生存。目前的工作旨在改善大西洋鲑（Salmo salar）饮食配方，作为AGD的预防性治疗。测试了四种具有不同定量组成功能成分的饮食，例如精氨酸，预混合物，植物提取物，核苷酸，β-葡聚糖以及维生素C和E。在第一个试验中，喂食了不同饮食的鱼接受了为期74天的百日咳假单胞菌挑战试验以及它们的存活率，采食量和生长性能，以及血浆特性和g组织病理学进行了分析。此外，还进行了第二项试验，从未暴露于AGD的鱼中分析了饲喂相同日粮的大西洋鲑鱼的粘液成分。结果表明功能成分对大西洋鲑鱼的存活和免疫反应具有积极作用。特别是，加入精氨酸，微量添加剂以及维生素C和E可以提高生存率，其中精氨酸是病原体保护的重要驱动力。这些功能性成分对无挑战性鱼类的黏液保护作用也得到了改善，这是由于其黏度更高以及溶菌酶和多糖含量增加所提示。总体，