1GMA - Gesellschaft für Marine Aquakultur mbH,Hafentörn 3,25761 Büsum,Germany.
3Institute of Human Nutrition and Food Science,University of Kiel,Hermann-Rodewald-Straße 6,24118 Kiel,Germany.
Animal. 2019 May;13(5):933-940. doi: 10.1017/S1751731118002458. Epub 2018 Oct 10.
The replacement of the finite and costly resource fish oil is an important task for aquaculture nutrition. A promising approach could be the use of plant bioactives that may have the potential to influence the metabolism and the synthesis of n-3 long chain polyunsaturated fatty acids, especially EPA (20:5n-3) and DHA (22:6n-3). In this study, the two phytochemicals resveratrol (RV) and genistein (G) were investigated for their effects on fish growth, nutrient utilization and body nutrient composition alongside their effects on whole body fatty acid (FA) composition. In a feeding trial lasting 8 weeks, rainbow trout (initial BW: 81.4±0.5 g) were held in a recirculating aquaculture system and fed six experimental diets with varying fish oil levels as plain variants or supplemented with 0.3% of dry matter (DM) of either RV or G. The six diets were as follows: diet F4 had 4% DM fish oil, diet F0 had 0% DM fish oil, diets F4+RV, F4+G, F0+RV and F0+G were equal to the diets F4 and F0, respectively, and supplemented with the phytochemicals RV and G. The feeding of the F0+RV diet resulted in reduced feed intake, growth rate and slightly reduced whole body lipid levels. At the same time, the amount of polyunsaturated FA and the n-3/n-6 ratio were significantly increased in whole body homogenates of rainbow trout fed diet F0+RV in comparison to the F0 control. The feeding of the F0+G diet led to reduced feed intake, slightly increased protein utilization but did not significantly affect the whole body FA composition. Overall, feeding the fish oil-free diet supplemented with the phytochemicals resulted in more pronounced effects on fish performance and FA composition than the single factors per se (dietary fish oil level or phytochemical). Present data indicate that G might not be of profitable use for trout nutrition. In terms of FA composition, RV could be a potentially useful complement for fish oil. However, the impairment of growth and performance parameters as observed in the present study discourages its use in trout diets.
替代有限且昂贵的鱼类资源是水产养殖营养的一项重要任务。一种有前途的方法可能是使用植物生物活性物质，这些物质可能具有影响代谢和 n-3 长链多不饱和脂肪酸（尤其是 EPA[20:5n-3]和 DHA[22:6n-3]）合成的潜力。在这项研究中，研究了两种植物化学物质白藜芦醇（RV）和染料木黄酮（G）对鱼类生长、养分利用和体组成以及对全身体脂组成的影响。在为期 8 周的饲养试验中，虹鳟（初始体重：81.4±0.5g）在循环水产养殖系统中饲养，并喂食六种实验饲料，这些饲料的鱼油量不同，作为纯品变体或用 0.3%干物质（DM）的 RV 或 G 补充。这六种饲料如下：饲料 F4 含有 4%DM 的鱼油，饲料 F0 含有 0%DM 的鱼油，饲料 F4+RV、F4+G、F0+RV 和 F0+G 分别与饲料 F4 和 F0 相等，并添加了 RV 和 G 两种植物化学物质。F0+RV 饲料的喂养导致摄食减少、生长速度降低和体脂水平略有降低。与此同时，与 F0 对照组相比，用 F0+RV 饲料喂养的虹鳟的体全匀浆中多不饱和脂肪酸和 n-3/n-6 比值显著增加。用 F0+G 饲料喂养导致摄食减少，蛋白质利用率略有增加，但对全身体脂组成没有显著影响。总体而言，与单独的因素（饲料鱼油水平或植物化学物质）相比，用不含鱼油的饲料补充植物化学物质对鱼类性能和 FA 组成的影响更为显著。目前的数据表明，G 可能对鳜鱼营养没有利润。就 FA 组成而言，RV 可能是鱼油的潜在有用补充。然而，在本研究中观察到的生长和性能参数的损害阻止了其在鳜鱼饲料中的使用。
