配饵中能量蛋白比与中华绒螫蟹生长之间的关系

在水簇箱中，用体重１９￣２５ｇ的中华绒螯蟹（Ｅｒｉｏｃｈｅｉｒ ｓｉｎｅｎｓｉｓ）对配饵中蛋白质的能蛋比与蟹生长之间的关系进行了研究，蛋白质设定为３６％、４０％和４４％３个水平，能蛋比设定了４０、４５和５０ｋＪ／ｋｇ３个水平，每个水平各有６个重复。结果表明，配饵中的粗蛋白含量和能量蛋白比与蟹体生长、蛋白增加量和饲料系数存在着显著的相关关系（Ｐ〈０．０５），蟹体的生长，ＳＧＲ和ＰＥＲ随饲料中蛋白质含     

中华绒螯蟹多倍体的诱导研究I.细胞松驰素B诱导中华绒螯蟹三倍体和四倍体胚胎

采用细胞松驰素Ｂ（Ｃ．Ｂ）处理法，研究了诱导中华绒螯蟹（Ｅｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓ）三倍体、四倍体的可能性和处理条件。实验所用Ｃ．Ｂ浓度为０．５～２．０ｍｇ／Ｌ，处理的起始时间分别在受精后１０～２５ｍｉｎ（诱导三倍体）和８．５～９．８ｈ（诱导四倍体），处理的持续时间为１０～２５ｍｉｎ。三倍体的适宜诱导条件为卵子在受精后１５ｍｉｎ，浓度为１．５ｍｇ／Ｌ的Ｃ．Ｂ溶液处理１８ｍｉｎ。三倍体诱导率最高可达５８．１８％。根据诱导三倍体的适宜Ｃ．Ｂ处理浓度和处理时间，用１．５ｍｇ／ＬＣ．Ｂ溶液处理卵子１８ｍｉｎ，获得了２９．４６％～５７．８９％的四倍体胚胎。另外，还对中华绒螯蟹三倍体、四倍体胚胎的诱导技术、诱导参数对胚胎发育的影响等有关问题进行了分析讨论     

苏北南部沿海几种蟹类蛋白和同工酶的比较研究

本文对苏北南部沿海中华绒螯蟹（Ｅｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓ）、天津厚蟹（Ｈｅｌｉｃｅｔｒｉｄｅｎｓｔｉｅｎｔｓｉｎｅｎｓｉｓ）、红螯相手蟹（Ｓｅｓａｒｍａｈａｅｍａｔｏｃｈｅｉｒ）和日本大眼蟹（Ｍａｃｒｏｐｈｔｈａｌｍｕｓｊａｐｏｎｉｃｕｓ）四种常见蟹的眼、肝、肌和卵组织以及中华绒螯蟹和天津厚蟹蟹苗的蛋白和ＬＤＨ、ＡＮＥＡ同工酶进行了比较研究。结果表明,四种蟹的蛋白和同工酶具明显的物种特异性和组织特异性;两种蟹苗的蛋白和同工酶酶谱在谱带数量、迁移率及酶活性上都存在差异。     

鱼类的能量需要量

若比较美洲鲶（ｃａｔｆｉｓｈ）和肉用仔鸡市售饲料的营养成分，粗蛋白质（ＣＰ）分别为３２％和１８％，代谢能（ＭＥ）为１２５６和１２９９ＫＪ／ｇ，几乎处于同一水平，能蛋比（ＭＥ／ＣＰ）为３９２５和７２１７。调查这两种饲料的效率，美洲鲶和肉用仔鸡的...     

黄鳝的营养素需要量及饲料最适能量蛋白比

用正交设计法Ｌ９（３＾４）配制九种试验饲料，对黄鳝配合饲料中蛋白质、脂肪、总能、无机盐需要量及最适能量蛋白比进行了研究，结果表明，影响黄鳝生长的主要因素是蛋白质和总能，黄鳝最佳生长所需饲料中蛋白质含量为３５．７％，总能为１１．５０￣１２．５０ｋＪ．ｇ＾－１饲料，脂肪含量３％￣４％，无机盐含量３％，总糖２４％￣３３％。黄鳝饲料的最适能量蛋白比（Ｅ／Ｐ＝ｋＪ．ｇ＾－１）为３１．６￣３８．９。     

有机养殖模式下中华绒螯蟹抗氧化防护和溶菌酶的活性

比较了有机和常规养殖模式下,体质量165~175g中华绒螯蟹鳃、肝胰脏和肌肉中溶菌酶活性、超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性以及丙二醛含量。结果显示,有机养殖模式下,中华绒螯蟹肝胰脏和肌肉中超氧化物歧化酶和过氧化氢酶活性显著高于常规养殖模式(P0.05),但鳃中超氧化物歧化酶和过氧化氢酶活性与常规养殖组差异不显著(P0.05);鳃、肝胰脏和肌肉中谷胱甘肽过氧化物酶活性均显著高于常规养殖模式(P0.05);鳃、肝胰脏和肌肉中丙二醛含量显著低于常规养殖模式(P0.05)。有机养殖模式下中华绒螯蟹肝胰脏中的溶菌酶活性显著高于常规养殖组(P0.05)。试验结果表明,有机养殖模式下中华绒螯蟹具有较高的抗氧化防护能力和抗菌能力。     

绒螯蟹三个种群形态判别比较

对长江水系中华绒螯蟹、莱茵河野生中华绒螯蟹和日本绒螯蟹三个种群的形态特征进行了判别研究。可数性状分析的结果表明，长江水系中华绒螯蟹、莱茵河野生中华绒螯蟹和日本绒螯蟹三个种群，两两之间差异极显著。聚类分析的结果，把长江水系中华绒螯蟹和莱茵河野生中华绒螯蟹划为一组，日本绒螯蟹为另一组。判别分析建立起三者的判别函数，雌雄蟹判别的正确率分别为83．1％、91．9％。     

中华绒螫蟹对11种饲料原料蛋白质和氨基酸的表观消化率

以氧化钇（Y2O3）作为指示剂，按照“70％基础饲料＋30％试验原料”的原则配制饲料，测定了体重（97．34±7．36）g的中华绒螯蟹对不同饲料原料蛋白质和氨基酸的表观消化率。试验选取鱼粉、血粉、肉骨粉、乌贼内脏粉、虾壳粉、啤酒酵母、豆粕、棉籽粕、菜籽粕、花生粕、玉米蛋白粉共11种商品蛋白质饲料原料。试验结果表明，中华绒螯蟹对不同饲料蛋白源的粗蛋白表观消化率为40．62％～89．75％，其中，鱼粉和血粉组的粗蛋白表观消化率分别为86．07％和89．75％，显著高于其他原料组；而菜籽粕（42．41％）和玉米蛋白粉组（40．62％）的粗蛋白消化率则明显低于其他饲料蛋白源（P〈0．05）。其他蛋白源的消化率大小顺序依次为：豆粕（77．94％）〉啤酒酵母（76．90％）〉虾壳粉（74．02％）〉肉骨粉（73．78％）〉棉籽粕（71．63％）〉花生粕（65．90％）〉乌贼内脏粉（63．51％）。在动物性蛋白源中，中华绒螯蟹对血粉和鱼粉的氨基酸消化率较高，二者的总氨基酸消化率均高于90％，试验结果还显示，蟹对乌贼内脏粉的氨基酸消化率最低，仅为63．51％；单细胞蛋白源啤酒酵母的总氨基酸消化率（86．77％）高于其他植物性蛋白源；在植物性蛋白源中，对棉籽粕的总氨基酸消化率最高（85．37％），其次是豆粕（79．41％）。本研究结果对评价不同饲料蛋白源的营养价值，以及开发中华绒螯蟹氨基酸营养平衡的人工配合饲料提供了参考和依据。     

不同配方饲料对稻田养殖中华绒螯蟹生长和效益的影响

在12块稻田中进行4种中华绒螯蟹饲料配方对比试验,蛋白含量分别为38.06%、33.43%、28.48%、25.32%.经90 d的养殖试验结果表明,蛋白含量为38.06%、脂肪含量为6.01%、钙磷比为1∶1.35的饲料组中华绒螯蟹生长最佳,利润最高.高营养水平的中华绒螯蟹配合饲料能促进生长,提高养殖产品的品质,显著增加效益.     

中华绒螯蟹种苗静水土池塘培育技术研究 Ⅱ-水质对幼体变态率和成活率的影响

１９９８年４月～６月利用总面积１９ｈｍ２的６口池塘比较研究了水质对中华绒螯蟹（Ｅｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓ）幼体变态率和成活率的影响。结果表明,水温低时,幼体变态所需的时间长,累积温度（日平均水温×变态所需的天数）高;溶氧大于５ｍｇ／Ｌ,提高幼体变态率和成活率的关键是处理好饵料和水质的关系。     

Evaluation of Digestible Energy and Protein for Growth and Nitrogen Retention in Juvenile Florida Pompano,Trachinotus carolinus

Juvenile Florida pompano (6.3 ± 0.50 g) were fed 1 of 12 diets formulated with an array of crude protein (340, 380, 420, 480, or 500 g/kg diet) and crude lipid (60, 100, 120, 160, or 180 g/kg diet) levels and estimated digestible protein to digestible energy (DP/DE) of 18.9–26.8 mg/kJ. In a second trial, apparent protein and energy digestibilities were empirically determined and coefficients used to calculate actual digestibilities. Digestible energy (DE) intake was 4.2–13.0 kJ/fish/d, and digestible protein (DP) intake was 0.13–0.32 g/fish/d. Average daily gain increased as a function of both DP and energy. Growth increased with increasing DP in all diets containing 24.0 mg/kJ DP/DE or greater until a plateau at 366 g DP/kg. Nitrogen gain was also a function of both DP and DE. Increasing energy at constant protein improved protein utilization. DP to maximize growth and nitrogen gain was between 356 and 366 g/kg. DE to attain maximum growth in juvenile Florida pompano is at least 15.4 MJ/kg with a DP/DE between 23.8 and 25.1 mg/kJ.     

饲料低蛋白、高脂肪和高消化能对斑点叉尾鮰

为了探讨高脂肪条件下不同的蛋白和能量水平对斑点叉尾鮰生长及体组成的影响,试验设2个蛋白水平(22%,28%),2个脂肪水平(10.0%,14.0%),2个消化能水平(12.56 kJ/g,14.23 kJ/g),共8组,分别为P28L10E14.23,P28L14E14.23,P22L10E14.23,P22L14E14.23,P28L10E12.56,P28L14E12.56,P22L10E12.56和P22L14E12.56。试验饲料配方使用鱼粉和豆粕调节蛋白含量,混合油脂(鱼油∶玉米油=1∶1)调节脂肪含量,α-淀粉、次粉和麸皮调节消化能含量,并以微晶纤维素为填充物,每组3个重复,每个重复20尾鱼(141.5?1.0) g。饲养60 d后,进行生产性能测定,并采集组织样本,测定相关指标。结果表明,鱼体末重(FW)、增重率(WG)、特定生长率(SGR)和饵料系数(FCR)不受饲料蛋白、脂肪和消化能单一营养水平影响(P>0.05);但与饲料蛋白、脂肪和消化能三者的交互作用(P<0.01)有关。胴体蛋白、脂肪含量与饲料脂肪和消化能水平相关(P<0.05)。由此可见,饲料过高脂肪和消化能对斑点叉尾鮰没有额外的促生长作用;饲料蛋白水平达到22%时,即可满足140~300 g斑点叉尾鮰的营养需要;饲料中22%的蛋白、10%的脂肪、12.56 kJ/g的消化能即可满足斑点叉尾鮰仔鱼的生长需要,同时又能保证其正常生理机能,建议可在实际生产配方中作参考值。     

饲料蛋白能量比对草鱼幼鱼生长性能、蛋白利用和体成分的影响

以鱼粉和豆粕为蛋白源,鱼油和豆油等比例混合油为脂肪源,采用4×4因子实验来确定草鱼(Ctenopharyngodon idellus)幼鱼饲料中的合适蛋白能量比(P/E),其中饲料蛋白水平分别为20%、25%、30%、35%,能量水平为12.5、13.7、15、16.2 k J/g,饲料蛋白能量比的范围为12.1~27.3 mg/k J,共16组饲料,每组设3个重复,连续投喂初体质量(16.85±0.29)g的草鱼幼鱼10周,研究饲料蛋白能量比对草鱼幼鱼生长性能、蛋白利用和体成分的影响。结果表明:(1)最高末体质量和特定生长率出现在P/E为18.3 mg/k J组,而P/E为16.0 mg/k J组的饲料系数最高,蛋白质效率和蛋白沉积率最高组分别为P/E 12.10 mg/k J组和15.20 mg/k J组。(2)P/E为27.30 mg/k J组的能量沉积率和总氮排泄率最大。(3)在同一饲料蛋白水平下,鱼体的脂肪含量随饲料能量水平升高而升高;在同一饲料能量水平下,鱼体的蛋白含量随饲料蛋白含量升高而升高。对生长、蛋白利用、体成分的实验结果进行综合分析,草鱼幼鱼饲料的最适蛋白含量为30%,最适P/E为19.5 mg/k J。     

Optimum Dietary Protein Level and Protein-to-Energy Ratio for Growth of Juvenile Korean Rockfish Sebastes schlegeli

An 8-wk feeding trial was conducted to estimate the optimum dietary protein level and protein-to-energy (P/E) ratio in juvenile Korean rockfish Sebastes schlegeli. Twenty experimental diets were formulated with four energy levels and five protein levels at each energy level. Four gross energy levels of 14.2, 16.5, 18.6, and 20.9 kJ/g diet were included at various crude protein (CP) levels. Diets containing CP at 30, 40, 45, 50, and 55% had either 14.2 or 16.5 kJ/g energy; those with CP levels of 35, 40, 45, 50, and 60% had either 18.6 or 20.9 kJ/ g energy. After 2 wk of conditioning, fish initially averaging 7.3 ± 0.04 g (means ± SD) were randomly distributed into net cages as groups of 20 fish. Each diet was fed to fish in three randomly selected net cages for 8 wk. After 8 wk of the feeding trial, weight gain (WG) of fish fed 50% and 55% CP with 14.2 kJ/g diet was significantly higher than those of fish fed 30% and 40% CP diets (P 0.05). WG of fish fed 45, 50, and 55% CP with 16.5 kJ/g diet was significantly higher than those of fish fed 30% and 40% CP diets (P < 0.05). WG of fish fed 60% CP with 18.6 kJ/g diet was significantly higher than those of fish fed 35, 40, and 45% CP diets. WG of fish fed 45% CP with 20.9 kJ/g diet was significantly higher than those of fish fed 35, 40, and 60% CP diets. Generally, feed efficiency (FE) and specific growth rate (SGR) showed a similar trend as WG. However, protein efficiency ratio (PER) was negatively related to dietary protein levels. WG of fish did not always increase with increasing dietary protein and energy levels. Comprehensive comparison among diets containing 40, 45, and 50% CP with different energy levels indicated that the increase in protein from 40 to 45% significantly increased WG (P < 0.05), but such effect was not significant when protein increased from 45 to 50% at all energy levels. Increasing dietary energy significantly increased WG of fish fed 40% and 45% CP at each energy level; however, there was no difference in WG of fish fed 50% CP with energy levels of 18.6 and 2.9 kJ/g diet. There was no significant difference in WG of fish fed 50% CP with 18.6 kJ/g or 45 and 50% CP with 20.9 kJ/g diet. Broken-line analysis of weight gain indicated that the optimum dietary protein level was 50.9 ± 1.1% and PIE ratio was 35.4 ± 0.8 mg/kJ with 14.2 kJ/g diet; the optimum dietary protein level was 49.3 ± 5.0% and P/E ratio was 30.2 ± 1.0 mg/kJ with 16.5 kJ/g diet; the optimum dietary protein level was 46.2 ± 9.2% and P/E ratio was 24.7 ± 4.9 mg/kJ with 18.6 kJ/g diet; and the optimum dietary protein level was 45.1 ± 1.8% and P/E ratio was 21.5 ±0.7 with 20.9 kJ/g diet. Therefore, these data indicated that the concept of P/E ratio must be restricted to diets containing adequate protein and energy levels. Based on WG, the optimum P/E ratio was between 21.5 and 35.4 mg protein/kJ gross energy in juvenile Korean rockfish when gross energy ranged from 14.2 to 20.9 kJ/g diet.     

Growth rate,feed utilization and energy metabolism of the African catfish,Clarias gariepinus (Burchell, 1822), as affected by dietary protein and energy content

Three feeding experiments were conducted in open circuit balance respirometers, to determine the effect of dietary protein level on growth rate, feed utilization and energy metabolism of Clarias gariepinus (Burchell). The feeding level was 2% of the fresh body weight per day. Three energy levels, 8.4, 12.6 and 16.8 kJ calculated metabolizable energy (ME) per gram of feed, were used, while crude protein levels in the diets were 20, 25, 30, 35 and 40%.Growth rate, heat production, metabolizability (ME as percentage of gross energy intake) and protein gain were maximal at the intermediate energy level. Digested protein per gram of growth was lowest at this energy level (determined ME = 13 kJ/g). Growth rate, metabolizability and protein gain increased as protein intake increased. There was no effect of the different protein levels on heat production. The efficiency of protein gain (% of the digestible protein intake) was highest (45–49%) at the intermediate energy level. Efficiency of protein gain (% of digestible intake) decreased slightly when protein intake increased. ME intake per gram of growth was minimal at the 8.4 kJ energy level and decreased at higher protein intake levels.At the highest energy level, growth rate was reduced compared to the intermediate energy level, but efficiency of energy gain, retention of fat and energy were highest. Much of the dietary fat was deposited as lipid reserves. After 4 weeks the growth rate, digestibility, metabolizability, and efficiency of protein- and energy gain (% of digestible or metabolizable intake respectively) were strongly reduced at this energy level.     

不同脂肪(能量)蛋白比饲料对梭鲈幼鱼生长的影响

比较了5种不同脂肪(能量)蛋白比的配合饲料对初始平均体重(7.75±1.17)g梭鲈幼鱼生长性能的影响。结果表明,投喂不同脂肪蛋白水平的饲料,以能量蛋白比为45.94kJ/g试验组的生长速度最快[SGR为(2.86±0.17)%/d]、饲料系数最低(FCR为1.57±0.12)、蛋白质沉积率和能量保留率最大,分别为98.44%±2.38%和30.88%±3.83%;以饲料中蛋白质含量、脂肪含量为变量因子,以梭鲈幼鱼的特定生长率、蛋白质沉积率和能量保留率为指标,通过二元二次回归方程得出梭鲈最大生长速度时饲料中蛋白质含量为39.80%,脂肪含量为8.79%,总能为18.53MJ/kg,脂肪蛋白比为0.22,能量蛋白比为46.56kJ/g;梭鲈获得最大的蛋白质沉积率时,饲料蛋白质含量为38.76%,脂肪含量为9.18%,总能为18.65MJ/kg,脂肪蛋白比为0.24,能量蛋白比为48.12kJ/g;梭鲈获得最大的能量保留率时饲料蛋白质含量为38.55%,脂肪含量为9.45%,总能为18.72MJ/kg,脂肪蛋白比为0.25,能量蛋白比为48.56kJ/g;饲料中脂肪水平的增加可以降低鱼类耗能时对蛋白质的需求量,表...     

The heat increment of feeding and heat loss relate to growth in Chinese shrimp, Fenneropenaeus chinensis (Osbeck 1765)

Three experiments were designed to investigate the heat increment of feeding (HiE) in Chinese shrimp, Fenneropenaeus chinensis . (1) Four groups of shrimp with different weight were fed at four rations to measure oxygen consumption in the following 24 h. (2) Four groups of shrimp with different weight were fed with four rations for 28 days. (3) Fish flesh, shrimp flesh, clam foot, polychaette worm, formulated diet and mixed diet were provided to six groups of shrimp for 30 days. The coefficient of heat increment of feeding ( C _HiE) values within 24 h after ingesting 1 g digestible protein (DP) and 1 kJ digestible energy (DE) were 18.57 kJ and 0.45. C _HiE values of 1 g DP and 1 kJ DE achieved in the second experiment were 25.06 kJ and 0.57. The energy cost of 1 g wet weight gain, 1 g protein gain and 1 kJ recovered energy were 13.94, 32.16 and 1.07 kJ. They accounted for 69.28%, 26.71% or 40.23% of HiE of the meals needed for these growths. The present results indicated that HiE was a fundamental property of the feed and the energy cost of growth accounted for different fraction when different feeds were ingested.     

Protein: energy ratio in practical diets for Nile tilapia Oreochromis niloticus

The present study was conducted to evaluate the interaction of protein and energy ratio in low protein (20, 25 and 30 %) diets for juvenile Nile tilapia (Oreochromis niloticus) (initial weight 7.44 ± 0.03 g). Dietary protein to energy (P/E) ratio of nine practical diets ranged from 66.84 to 115.14 mg protein/kcal energy. Each diet was randomly assigned to four replicate groups of fifteen fish. After 10 weeks, Fish fed the lowest dietary protein (20 %) and lowest energy (2,600 kcal/kg) diets were significantly smaller than fish maintained on D5 (25/2800) and D6 (30/2800), However, there were no significant differences among all the treatments except D1. The whole body moisture and protein levels were significantly influenced by dietary protein and energy content. Whole body energy content and digestible energy retention were significantly influenced by energy content of the diet. Conversely, dietary protein level significantly influenced protein retention but it did not influence digestible energy retention. Under the reported conditions, the response of tilapia to dietary energy or protein was seen only at the lower levels of inclusion and tilapia demonstrated limited protein sparing as dietary energy was increased. However, this did modify the carcass composition through higher dietary energy.     

Energy and nitrogen partitioning in 250 g Atlantic cod (Gadus morhua L.) given graded levels of feed with different protein and lipid content

The effects of feed intake level on energy and nitrogen partitioning were studied in juvenile Atlantic cod (250 g) fed two fish meal based diets differing in protein and lipid content (54:31 and 65:16) at 10 °C. Replicate groups of cod were feed deprived for 32 days or fed one of the two diets at 25, 50, 75 or 100% of group satiation for 60 days. Feed intake and oxygen consumption were measured daily and weights and chemical composition of carcass, liver, viscera and whole body were measured at start and end. Diet digestibilities were assessed in a separate experiment.

The whole body and carcass growth rates at a given feed intake did not differ between dietary groups, but the liver grew faster in the fish fed the low protein diet, resulting in higher hepatosomatic indices at the end of the experiment in the groups fed this diet.

The efficiency of utilisation of digestible nitrogen for growth (k_DNg) was higher for the low protein diet (0.73 ± 0.02) than for the high protein diet (0.53 ± 0.05), resulting in higher nitrogen retention at a given nitrogen intake. No difference in percentage nitrogen retention was seen in full-fed fish however (31.2 ± 2.5 and 28.4 ± 1.6% for the low protein and high protein diets, respectively). This can be explained by higher nitrogen intake in the fish fed the high protein diet, resulting in a smaller proportion of the intake being used for maintenance.

There was no difference in energy utilisation between dietary groups. The digestible energy requirement for maintenance (DE_maint) was 53.8 ± 0.9 kJ kg^− 1 d^− 1 (42.3 ± 0.7 kJ kg^− 0.8 d^− 1) and the utilisation efficiency for growth (k_DEg) was 0.80 ± 0.02. The energy retention in full-fed fish was 31.3 ± 3.5 and 31.7 ± 1.0% for the low protein and high protein diets, respectively. The deposited energy was distributed in approximately equal proportions in the liver and carcass, whereas viscera accounted for a minor proportion. At a given energy intake, the fish fed the high protein diet deposited more energy in the carcass and less in the liver than did those fed the low protein diet.     

Optimum Dietary Protein Level and Protein‐to‐energy Ratio for Growth of Juvenile Parrot Fish,Oplegnathus fasciatus

An 8‐wk feeding trial was conducted to estimate the optimum dietary protein level and protein‐to‐energy (P/E) ratio in juvenile parrot fish, Oplegnathus fasciatus. Eight experimental diets were formulated with two energy levels and four protein levels for each energy level. Diets containing crude protein (CP) at 35, 40, 45, and 50% had either 12.5 or 14.6 kJ/g of energy. Fish averaging 7.1 ± 0.06 g (mean ± SD) were fed one of the experimental diets for 8 wk. At the end of the feeding trial, weight gain (WG) of fish fed 45 and 50% CP in the 12.5 kJ/g diet was significantly higher than fish fed the 35% CP diet (P < 0.05). WG of the fish fed 45 and 50% CP in the 14.6 kJ/g diet was significantly higher than fish fed the 35 and 40% CP diets (P < 0.05). Fish fed the 14.6 kJ/g diet had a higher WG compared with fish fed the 12.5 kJ/g diet at all CP levels. Feed efficiency (FE) and specific growth rate (SGR) showed a similar trend to the WG. WG, FE, and SGR improved with increasing dietary protein levels up to 45% and remained constant at 50% CP for both energy levels. However, protein efficiency ratio was negatively related to dietary protein levels. The results suggested that the optimum level of protein and the optimum P/E ratio for juvenile parrot fish should be 45% and 31.1 mg protein/kJ, respectively, in a diet containing 14.6 kJ/g energy.