Fish regulate cellular membrane fluidity in response to temperature by restructuring membrane lipid composition. This study evaluated the effect of diet and temperature on liver membranes in steelhead trout, an important aquaculture species. Oncorhynchus mykiss were fed three commercial diets with different levels of PUFA (lower (L‐n3); medium (M‐n3); higher (H‐n3) omega 3) from marine, terrestrial, and vegetable oils; the effect of temperature changes on liver membrane was measured. Fish fed the H‐n3 diet had the most linear response in Raman spectroscopy, indicating that they can adapt to changes in temperature with the least effect on liver membrane, due to the higher polyunsaturate:saturate ratio in the diet, counteracting the influence of low temperature. L‐n3‐fed fish presented increased membrane fluidity at all temperatures, highlighting the influence of terrestrial fatty acids on membrane properties. These results underscore changes in sterol:phospholipid ratios as a key response for membrane adaptability to environmental changes, and the necessity to include environmental variables when testing new diets. Substitution of fish oil with vegetable oils may compromise sterol:phospholipid ratios, affecting membrane adaptability. This study shows changes at cellular level in liver tissue for fish fed different diets and subjected to different water temperatures.

中文翻译：

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饮食和温度会影响硬头鳟鱼的肝脂和膜特性（Oncorhynchus mykiss）

鱼通过重组膜脂质成分调节温度，从而调节细胞膜的流动性。这项研究评估了饮食和温度对硬头鳟鱼（一种重要的水产养殖种类）肝膜的影响。短吻鳄分别从海洋，陆地和植物油中饲喂了三种不同日粮的PUFA（较低（L-n3）；中等（M-n3）；较高（H-n3）ω3）。测量温度变化对肝膜的影响。饲喂H-n3日粮的鱼在拉曼光谱中具有最大的线性响应，这表明由于日粮中多不饱和物：饱和物的比例较高，它们可以适应温度变化而对肝膜的影响最小，从而抵消了低热量的影响。温度。Ln3喂养的鱼在所有温度下的膜流动性均增加，突出了陆生脂肪酸对膜特性的影响。这些结果强调了固醇：磷脂比例的变化是膜对环境变化适应性的关键反应，并且在测试新饮食时必须包括环境变量。用植物油代替鱼油可能会损害甾醇：磷脂比例，从而影响膜的适应性。这项研究表明，饲喂不同饮食和不同水温的鱼类肝脏组织中细胞水平的变化。