The present study aimed to determine the ideal ratios of digestible essential amino acids (EAAs) for pacu (Piaractus mesopotamicus) juveniles by the amino acid (AA) deletion method. A completely randomized design which consisted of 11 treatments and three replicates each was used. The treatments included a control diet (CD) containing 55% of nonpurified natural ingredients and 45% of purified synthetic amino acids and ingredients, and other ten isonitrogenous and isoenergetic EAA limiting diets (LDs), each being deficient in 44.4 ± 0.02% of the respective EAA. Pacu juveniles with initial average body weight of 6.22 ± 0.09 g were distributed among 33 fiber glass tanks. Fish were fed with semipurified and extruded diets for 113 days two times a day until apparent satiation. The ideal ratio of each dietary EAA was calculated on the basis of the relationship between body N retention and amount of EAA deleted from the respective EAA LD. Based on the AA deletion method, the ideal ratios of digestible EAAs for pacu juveniles, relative to lysine requirement of 100% were estimated as: methionine 14.6%, threonine 35.0%, tryptophan 6.6%, arginine 62.8%, histidine 13.6%, isoleucine 26.3%, leucine 43.7%, phenylalanine 27.2%, and valine 35.8%.

中文翻译：

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用氨基酸缺失法评估pacu，美索不达米亚（Piaractus mesopotamicus），幼鱼的可消化必需氨基酸的理想比例

本研究旨在确定Pacu（Piaractus mesopotamicus）的可消化必需氨基酸（EAAs）的理想比例）的少年，通过氨基酸（AA）删除方法。使用完全随机的设计，该设计包含11种治疗方法，每个治疗重复3次。这些治疗方法包括对照饮食（CD），其中含有55％的未纯化天然成分和45％的纯化合成氨基酸和成分，以及其他十种等氮和等能EAA限制性饮食（LDs），每种饮食均缺乏44.4±0.02％的饮食。各自的EAA。最初平均体重为6.22±0.09 g的Pacu幼虫分布在33个玻璃纤维储罐中。每天两次给鱼类喂食半纯化和膨化饲料113天，直到明显饱食为止。每种饮食EAA的理想比例是根据人体N保留量和从相应EAA LD中删除的EAA量之间的关系计算得出的。根据AA删除方法，