Branched-chain amino acids (BCAAs), leucine, isoleucine and valine have an enormous functional significance because of their involvement in fish physiology. Branched-chain amino acids are not limited to act as substrates of protein synthesis but are also part of the protein synthesis regulation. BCAAs regulate various key signalling pathways. Leucine has a pivotal role in mTOR activation, while isoleucine and valine have a predominant energy and glucose metabolism action. Research over the years has highlighted the importance of dietary BCAAs levels on the growth and development of fish. The available data suggest that fish require slightly higher amounts of BCAAs at the initial stage than at the latter stages of life. BCAAs requirements of different fish species have indicated wide variations: 11.5 to 91.0 g leucine/kg dietary protein, 15.4 to 42.3 g isoleucine/kg dietary protein and 17.7 to 46.91 g valine/kg dietary protein. This review paper covers the dietary BCAA requirements of various fish species and the modulation action of BCAAs on vital functions, as protein synthesis, metabolic pathway, glucose transportation and immune response.

中文翻译：

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支链氨基酸对不同鱼类生长、生理和代谢的作用：综述

支链氨基酸 (BCAA)、亮氨酸、异亮氨酸和缬氨酸因其参与鱼类生理学而具有巨大的功能意义。支链氨基酸不限于作为蛋白质合成的底物，而且也是蛋白质合成调节的一部分。BCAAs 调节各种关键的信号通路。亮氨酸在 mTOR 激活中起关键作用，而异亮氨酸和缬氨酸具有主要的能量和葡萄糖代谢作用。多年来的研究强调了膳食支链氨基酸水平对鱼类生长和发育的重要性。现有数据表明，鱼在生命的初始阶段需要比在生命后期阶段略高的支链氨基酸。不同鱼类对支链氨基酸的需求表明存在很大差异：11.5 至 91.0 克亮氨酸/千克膳食蛋白质，15.4 至 42。3 g 异亮氨酸/kg 膳食蛋白质和 17.7 至 46.91 g 缬氨酸/kg 膳食蛋白质。这篇综述论文涵盖了各种鱼类的膳食支链氨基酸需求以及支链氨基酸对重要功能的调节作用，如蛋白质合成、代谢途径、葡萄糖转运和免疫反应。