Due to increasing demand of ingredients of animal origin, studies on the availability of nutrients in ingredients of plant origin are worthy in carnivorous species including bullfrog. This study aimed to determine apparent digestibility coefficients (ADCs) of amino acids (AAs) in three ingredients as plant protein sources (soybean protein concentrate (SPC), corn gluten meal 60 % (CGM), soybean meal (SM)) and two ingredients as plant energy sources (corn grain (CG) and wheat bran (WB)) which commonly use in bullfrog diets. A reference diet and five test diets containing 69.5 % of the reference diet, 30 % of each test ingredient and 0.5 % of chromium (III) oxide as an inert marker were prepared. Among plant protein ingredients, CGM showed better digestibility of essential amino acids (EAAs) (> 80 %) at the three post-metamorphic (initial, growing and finishing) phases of bullfrog development, except tryptophan which presented a low digestibility at growing and finishing phases. Among plant energy ingredients, CG presented better digestibility of AAs at both initial and growing phases than WB which showed better digestibility only at finishing phase. It was observed that methionine and lysine are the most limiting EAAs in tested ingredients, indicating that additional amounts of these AAs should be supplemented when these ingredients are used in bullfrog diets.

中文翻译：

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牛蛙（Lithobates catesbeianus）植物源蛋白质和能量成分的氨基酸消化率


由于对动物源成分的需求不断增加，对包括牛蛙在内的肉食性物种中植物源成分中营养物质的可用性的研究是有价值的。本研究旨在确定三种植物蛋白源成分（浓缩大豆蛋白 (SPC)、玉米蛋白粉 60% (CGM)、豆粕 (SM)）和两种成分中氨基酸 (AA) 的表观消化系数 (ADC)作为牛蛙饲料中常用的植物能源（玉米粒（CG）和麦麸（WB））。制备了参考饮食和五种测试饮食，其中包含 69.5% 的参考饮食、30% 的每种测试成分和 0.5% 的作为惰性标记的氧化铬 (III)。在植物蛋白成分中，CGM 在牛蛙发育的三个变态后（初始、生长期和肥育期）阶段对必需氨基酸 (EAA) 的消化率较高（> 80%），但色氨酸在生长期和肥育期的消化率较低。阶段。在植物能量成分中，CG 在初始阶段和生长期均表现出比 WB 更好的 AA 消化率，而 WB 仅在肥育阶段表现出更好的消化率。据观察，蛋氨酸和赖氨酸是测试成分中最受限制的 EAA，这表明当这些成分用于牛蛙日粮时，应额外补充这些 AA。