In this study, we evaluated the growth performance, body composition and feed efficiency, muscle and gut histology, blood haematology and plasma biochemical parameters and the activity of antioxidant enzymes in the liver of Nile tilapia fed diets supplemented with betaine. Increasing doses (0.00, 0.50, 1.00 and 2.00 g kg⁻¹) were added to a basal diet and randomly assigned to three groups, composed of 12 fish (27.76 ± 1.31 g) in each experimental units. The fish were fed to satiation four times a day during 100 days. Dietary inclusion of 0.50 g kg⁻¹ of betaine resulted in greater results in weight gain, daily weight gain, specific growth rate, as well as energy retention rate. Dietary inclusion of betaine resulted in less height, width and thickness of the tunic of the gut folds. Fish fed 0.50 and 1.00 g kg⁻¹ of dietary betaine showed higher plasma glucose. The concentration of substances reactive to thiobarbituric acid was lower in fish fed with 0.50 g kg⁻¹ of dietary betaine, while those fed with 1.00 g kg⁻¹ dietary betaine show greater activity of the catalase enzyme. The dietary inclusion of 0.50 g kg⁻¹ of betaine improves growth performance probably by reducing lipid peroxidation.

中文翻译：

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甜菜碱的膳食补充剂可改善尼罗罗非鱼的生长性能并减少脂质过氧化

在这项研究中，我们评估了添加甜菜碱的尼罗罗非鱼饲料的生长性能、身体成分和饲料效率、肌肉和肠道组织学、血液血液学和血浆生化参数以及肝脏中抗氧化酶的活性。将增加剂量（0.00、0.50、1.00 和 2.00 g kg ^-1）添加到基础饮食中，并随机分配到三组，每个实验单位由 12 条鱼（27.76 ± 1.31 g）组成。在 100 天内，每天四次将鱼喂饱。膳食添加量 0.50 g kg ^-1甜菜碱在体重增加、每日体重增加、特定生长率以及能量保留率方面产生了更大的结果。甜菜碱的膳食添加导致肠皱襞外衣的高度、宽度和厚度减小。饲喂 0.50 和 1.00 g kg ^-1膳食甜菜碱的鱼表现出更高的血浆葡萄糖。^{饲喂 0.50 g kg -1}日粮甜菜碱的鱼中与硫代巴比妥酸反应的物质浓度较低，而饲喂 1.00 g kg ^-1日粮甜菜碱的鱼表现出更大的过氧化氢酶活性。日粮中添加 0.50 g kg ^-1甜菜碱可能通过减少脂质过氧化来提高生长性能。