Abstract This study aimed to evaluate performance, biochemical, hematological and tissue parameters in tambaqui Colossoma macropomum juveniles with initial average weight of 18.0 ± 4.0 g submitted to feed restriction. Three feeding protocols were tested for 56 days: continuous feeding (control); feeding for six days and feed restriction for one day a week (F6R1); and feeding for five days and restriction for two days a week (F5R2). Growth performance was evaluated as weight (W), feed intake (FI), feed conversion ratio (FCR), specific growth rate (SGR) and protein efficiency ratio (PER) at 28 days and from 29 to 56 days of experiment. Blood samples were collected at 28 days (after restriction period in F5R2 and F6R1) and before (at 54 days) and after feed restriction period (at 56 days) to determine hematocrit, hemoglobin, plasma glucose, triglycerides, cholesterol and protein levels. Liver and muscle lipid concentrations, the hepatosomatic index and the mesenteric fat index were evaluated after 28 and 56 days. After 28 days there was a decrease in W, FI and SGR and a better FCR for F5R2, when compared to the control. From day 29 to day 56 there was a decrease in W, FI and a better FCR for F5R2, when compared to the control, while SGR and PER of restricted groups were similar to the control. After 28 days there was a decrease in hematocrit and triglycerides for F5R2, while there was no significant difference in hemoglobin, glucose, cholesterol and protein. Hematocrit was significantly lower in F5R2 group, while there was no treatment, period (54 and 56 days) and interaction between them for hemoglobin concentrations. For glucose, there was an effect of the treatment, as well as an effect of the period but there was no interaction between them. For triglycerides levels there was an effect of treatment, period and interaction between them. Protein and cholesterol levels were influenced only by period and both variables showed an increase in their levels at 56 days, compared to 54 days. After 28 days there was no significant difference for liver lipid levels, muscle lipid and the mesenteric fat index in all treatments; however, there was a decrease in the hepatosomatic index in F5R2. After 56 days there was a decrease in liver lipid levels and the hepatosomatic index with the increase in the restriction period, but there was no significant difference for muscle lipid levels and the mesenteric fat index. Juveniles of C. macropomum submitted to feed restriction for one day a week (F6R1), maintained their body reserves and hematological and biochemistry variables (except for triglycerides at 56 days) unchanged and showed good performance, similar to animals continuously fed for 56 days. However, due to the great heterogeneity of the animals, obtained mainly at the end of the experimental period (56 days), it is recommended to carry out periodic weight classifications for the production of this species in RAS.

中文翻译：

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在循环水产养殖系统（RAS）下限制喂食作为 Colossoma macropomum 幼鱼的饲养管理策略

摘要 本研究旨在评估初始平均体重为 18.0 ± 4.0 g 且接受饲料限制的 tambaqui Colossoma macropomum 幼鱼的性能、生化、血液学和组织参数。三种喂养方案进行了 56 天的测试：连续喂养（对照）；喂食六天，每周限制喂食一天（F6R1）；每周喂食五天，限制两天（F5R2）。在第 28 天和第 29 至 56 天的实验中，以体重 (W)、采食量 (FI)、饲料转化率 (FCR)、比生长率 (SGR) 和蛋白质效率比 (PER) 来评估生长性能。在第 28 天（在 F5R2 和 F6R1 限制期之后）和之前（第 54 天）和之后（第 56 天）收集血液样本以确定血细胞比容、血红蛋白、血浆葡萄糖、甘油三酯、胆固醇和蛋白质水平。在 28 天和 56 天后评估肝脏和肌肉脂质浓度、肝体指数和肠系膜脂肪指数。28 天后，与对照相比，F5R2 的 W、FI 和 SGR 降低，FCR 更好。从第 29 天到第 56 天，与对照相比，F5R2 的 W、FI 和 FCR 降低，而限制组的 SGR 和 PER 与对照相似。28 天后 F5R2 的血细胞比容和甘油三酯下降，而血红蛋白、葡萄糖、胆固醇和蛋白质没有显着差异。F5R2 组的血细胞比容显着降低，而没有治疗、周期（54 天和 56 天）以及它们之间对血红蛋白浓度的相互作用。对于葡萄糖，有治疗的效果，以及时期的影响，但它们之间没有相互作用。对于甘油三酯水平，治疗、周期和它们之间的相互作用有影响。蛋白质和胆固醇水平仅受周期影响，与 54 天相比，这两个变量在 56 天时的水平均有所增加。28天后，所有处理组肝脂质水平、肌肉脂质和肠系膜脂肪指数均无显着差异；然而，F5R2 中的肝体指数下降。56天后，肝脏脂质水平和肝体指数随着限制期的增加而下降，但肌肉脂质水平和肠系膜脂肪指数没有显着差异。C. macropomum 幼鱼每周限制喂食一天 (F6R1)，保持它们的身体储备和血液学和生物化学变量（56 天时的甘油三酯除外）不变并显示出良好的性能，类似于连续喂养 56 天的动物。然而，由于动物的异质性很大，主要在实验期结束时（56 天）获得，建议在 RAS 中对该物种的生产进行定期体重分类。