The effective inclusion of rapeseed protein products as fishmeal alternatives in diets for carnivorous fish is still limited. Previous studies observed restrictions in both nutrient utilization and feed intake. Contents of nitrogen-free extracts (NfE) and anti-nutritive substances (ANFs) were made responsible for the latter mentioned limitations. Consequently, a highly purified rapeseed protein isolate with high protein content and low levels of both NfE and ANF was investigated in this study. In the first experiment, digestibility of the rapeseed protein isolate was determined. In the second experiment, the fishmeal portion (190 g kg^-1) of a control diet was gradually replaced by rapeseed protein isolate to 33%, 66% and 100% of digestible protein and energy. Diets were fed twice per day to apparent satiation to triplicate groups of rainbow trout (Oncorhynchus mykiss). After 56 days of feeding, growth performance and health parameters were evaluated. Protein digestibility of the rapeseed protein isolate was 95.2%, and up to 66% of dietary fishmeal could be replaced without significantly affecting growth or health parameters. Total replacement of fishmeal led to significantly reduced feed intake and consequently reduced growth performance.

中文翻译：

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高纯度油菜籽分离蛋白作为鱼粉替代品对虹鳟（Oncorhynchus mykiss）日粮营养消化率和生长性能的影响

将油菜籽蛋白产品作为鱼粉替代品有效纳入肉食性鱼类的饮食仍然有限。以前的研究观察到营养利用和饲料摄入量都受到限制。无氮提取物 (NfE) 和抗营养物质 (ANF) 的含量是造成后者提到的局限性的原因。因此，在本研究中研究了具有高蛋白质含量和低水平 NfE 和 ANF 的高度纯化的油菜籽分离蛋白。在第一个实验中，确定了油菜籽分离蛋白的消化率。在第二个实验中，鱼粉部分（190 g kg ^-1) 的对照日粮逐渐被油菜籽分离蛋白替代至 33%、66% 和 100% 的可消化蛋白质和能量。每天饲喂两次日粮至三份虹鳟鱼 ( Oncorhynchus mykiss ) 的明显饱腹感。饲养 56 天后，评估生长性能和健康参数。油菜籽分离蛋白的蛋白质消化率为 95.2%，可替代高达 66% 的膳食鱼粉，而不会显着影响生长或健康参数。鱼粉的完全替代导致饲料摄入量显着降低，从而降低了生长性能。