Abstract：
The effect of diets with various dietary MUFA content and n-6/n-3 ratios, diets 1 (55.33, 1.00), 2 (25.30, 1.00), 3 (55.13, 2.05), 4 (24.92, 2.03), 5 (54.94, 8.06) and 6 (24.91, 8.06) and a control diet with fish oil (FO), diet 7 (33.60, 5.97), was studied on growth and digestive physiology of rainbow trout, Oncorhynchus mykiss. Juveniles, 14.65 g ± 0.17, were fed the experimental diets for eight weeks. Those fish fed diet 1 (55.33, 1.00) had the lowest growth and nutritional indices, while fish fed diet 6 (24.91, 8.06) possessed the highest indices. However, fish fed D7 (33.60, 5.97) was intermediate in this regard. Proximate body composition results revealed no significant differences among various experimental groups (P > 0.05). Fish fed on diet 1 possessed the highest alkaline protease activity, while fish raised on diet 2 showed the lowest enzyme activity (P < 0.05). Fish fed on diets 1, 3 and 4 had the highest lipase activity (P > 0.05). Amylase activity and intestinal parameters did not differ among groups (P > 0.05). MUFA contents of liver and muscle reflected the MUFA contents of the diets; however, liver PUFA contents was not affected by dietary PUFA contents (P < 0.05). However, 18:3n-3 contents of liver decreased as dietary n-6/n-3 ratio increased (P < 0.05). Furthermore, the liver 20:4n-6 contents considerably increased as dietary n-6/n-3 increased to 8.06 (P < 0.05). Muscle 22:6n-3 content of groups 1 to 6 was lower than group 7 (P < 0.05). In conclusion, rainbow trout was considerably capable of de novo synthesis of 22:6n-3. Meanwhile, increasing dietary n-6/n-3 ratio to 8.06 decreased the muscle 22:6n-3 content which requires further considerations regarding fish immune competence and nutritional quality for human consumption.
摘要：
具有不同膳食MUFA含量和n-6/n-3比率的膳食的影响，饮食1（55.33，1.00），2（25.30，1.00），3(55.13,2.05),4（24.92，2.03），5（54.94，8.06）和6（24.91，8.06）以及含鱼油（FO）的对照饮食，饮食7（33.60，5.97），对虹鳟鱼的生长和消化生理进行了研究，Oncorhynchusmykiss。青少年,14.65g±0.17,饲喂实验饮食八周。饲喂饮食1（55.33，1.00）的鱼的生长和营养指数最低，而鱼饲喂饮食6（24.91，8.06）的指数最高。然而,在这方面，饲喂D7（33.60，5.97）的鱼处于中等水平。身体成分测定结果显示各实验组之间无显著差异(P>0.05)。以饮食1为食的鱼具有最高的碱性蛋白酶活性，而饲粮2饲养的鱼酶活性最低(P<0.05)。饲喂日粮1、3和4的鱼具有最高的脂肪酶活性(P>0.05)。各组间淀粉酶活性和肠道参数无差异(P>0.05)。肝脏和肌肉的MUFA含量反映了饮食中的MUFA含量；然而，肝脏PUFA含量不受饲粮PUFA含量的影响(P<0.05)。然而,肝脏18:3n-3含量随饲料n-6/n-3比值的增加而降低(P<0.05)。此外，随着饲粮n-6/n-3增加到8.06，肝脏20：4n-6含量显着增加（P<0.05）。第1~6组肌肉22:6n-3含量低于第7组(P<0.05)。总之,虹鳟鱼能够从头合成22：6n-3。同时,将饮食中的n-6/n-3比率增加到8.06会降低肌肉22：6n-3的含量，这需要进一步考虑鱼类的免疫能力和人类食用的营养质量。
