山羊短期育肥效果观察

本试验选用４月龄的南江黄羊与本地山羊杂交一代羊和本地山羊在农户条件下进行为期 ６０ｄ短期育肥,试验结果表明：本地山羊试验１组（放牧加补饲）平均日增重较对照组（传统饲养法）增加 ２７．４３ｇ,差异极显著（Ｐ＜０．０１）,增收 １１．４８ 元,增加纯利润 ３．７８ 元。南×本杂交一代山羊试验 ２组（放牧加补饲）比本地山羊对照组平均日增重提高５６．２６ｇ,差异极显著（Ｐ＜０．０１）,增收２３．５９元,增加纯利润１３．６９元;而与本地山羊试验１组比较,平均日增重提高２８．８３ｇ,差异极显著（Ｐ＜０．０１）,增收１２．１１元,增加纯利润９．９１元。     

水库网箱养殖罗非鱼及其生态经济效益研究

在水库中连续３年设置网箱养殖罗非鱼，按４．５￣６ｋｇ／ｍ＾３放养量投放鱼种（平均规格６３￣９５ｇ／尾），饲养１００天左右，平均规格达到３７４￣４３８．８ｇ尾产量达２７．０￣３２．６ｋｇ／ｍ＾２，饲料系数１．３￣１．７５，利润率达５６．９％￣７５．２％，网箱养鱼能量转移率１７．９％￣２３．９６％。     

不同营养水平对膨泽鲫春片鱼种生长影响的研究

采用Ｌ９（３＾４）正交设计法,配制九种不同能量、蛋白质、有效磷水平的配合饲料喂养彭泽鲫春片鱼种,测定鱼体的增重、试验结果为：第１－９组的日增重分别为２．４９、２．２８、１．８３、２．１４、２．１９、１．８７、３．１１、３．１０和２．６７ｇ,日增重率分别为０．７６％、０．７０％￣０．５６％、０．６７％、０．６５％、０．５６％、０．９１％、０．９１％和０．８６％,相地增重率分别为３３．６３％、３０．７     

生长猪日粮中添加植酸酶的效果研究

用一个饲养试验和一个消化试验研究了１０００ｍｇ／ｋｇ植酸酶对生长猪生产性能和养分利用率的影响。饲养试验将１６头４５ｋｇ左右的长白ｘ荣昌Ｆ１杂交公猪随机分为２组，每组８个圈，每圈１头，分别喂给基础日粮、基础日粮＋１０００ｍｇ／ｋｇ植酸酶两种日粮。饲养试验开始后第２１ｄ采用全收粪法进行预试期７ｄ和正试期５ｄ的消化试验。结果表明：在４５ｋｇ左右生长猪日粮中添加１０００ｍｇ／ｋｇ植酸酶，日增重提高８．１５％（Ｐ＜０．０５），饲料效率改善４．１８％（Ｐ＜０．０５）；生长猪日粮添加植酸酶对干物质、粗蛋白质、粗脂肪、粗纤维的表现消化率分别提高１．１８％、２．７１％。５．０９％和１．５８％，统计上差异均不显著（Ｐ＞０．０５）。钙和磷的表观消化率分别提高１９．２２％和６８．００％，差异显著（Ｐ＜０．０５）。     

EM生物发酵液在育肥猪上的应用效果

应用ＥＭ发酵液发酵饲料开展育肥猪试验,经 １２７ｄ的饲喂,试验和对照组分别由 １６．８ｋｇ和２０．０ｋｇ平均体重起试,试终出栏体重分别达到９４．８ｋｇ和９５．５ｋｇ,由组间差异显著（Ｐ＜０．０５）最终达到不显著（Ｐ＞０．０５）;试验组较对照组头均日增重提高１９．３ｇ;头平均减少饲料消耗８．６ｋｇ,料重比较对照组降低６．２％;缩短饲养周期１０ｄ,节省饲料２２．９ｋｇ;增加了养殖效益,试验期内头均增收５０．６元。     

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。     

铬盐对鲤生长和饲料转化率的影响

以０．５ｍｇ／ｋｇ铬盐饲料饲喂１龄鲤６５ｄ和３月龄鲤３０ｄ,相对生长率分别提高１３．７９％和２０．６９％饲料转化率提高２１．８３％和２６．０％。表明铬盐有促进鱼类生长作用和提高饲料转化率的效应,而铬盐对鱼体营养成分的作用不明显。但铬盐对对高血糖症鱼的作用是低剂量各（２．５μｇ／ｋｇ体重）使血糖明显下降,高剂量（６０μｇ／ｋｇ体重）则使血糖明显升高;铬盐含量０．５ｍｇ／ｋｇ饲料使高血糖症鱼的血糖下降     

TF血浆蛋白粉在断奶仔猪日粮中的应用对比试验

本试验选用２９日龄（２８天断奶）的杜×长×大断奶仔猪４５头,按体重随机分为３组,每组１５头。试验Ⅰ、Ⅱ组为对照组,Ⅲ组为试验组。试验Ⅰ组只喂基础日粮,Ⅱ、Ⅲ组分别添加６％的ＳＤＰＰ_１（进口血浆蛋白）、ＴＦ血浆蛋白粉,试验结果表明：试验Ⅰ、Ⅱ、Ⅲ组的日增重分别为１７２．５ｇ、２４１．２ｇ和２４２．８ｇ,Ⅰ组与其它２组均差异极显著（Ｐ＜０．０１）;Ⅱ、Ⅲ组之间差异不显著（Ｐ＜０．０５）,从料肉比看,Ⅰ组与其它２组均差异极显著（Ｐ＜０．０１）,Ⅱ、Ⅲ组之间差异不显著（Ｐ＞０．０５）、整个试验期间,仅试验Ⅰ组有４头仔猪发生腹泻,腹泻发生率为２６．７％。经分析,每增重１ｋｇ,添加ＴＦ比添加ＳＤＰＰ_１节省费用１．３４元,效果显著。表明ＴＦ喷干血浆蛋白粉无论在免疫、促长,还是经济效益方面均效果明显,是取代进口的理想产品。     

实用饲料成分和蛋氨酸锰对肉鸡组织锰利用的影响

选用 ４８０只肉公雏,在玉米－豆粕型饲粮中分别添加 １０％麦麸、１０％米糠、６％菜籽粕,补加蛋氨酸锰依次为０,６０．１２０,１８０ｍｇ／ｋｇ,研究试验成分及补加蛋氨酸锰对肉鸡组织锰利用的影响。试鸡１日龄开始饲喂试验饲粮,试验２１ｄ。结果表明,添加１０％麦麸、１０％米糠均显著降低肉鸡骨、胆汁、胰腺锰（Ｐ＜０．０５或Ｐ＜０．０１）,补加蛋氨酸锰６０ｍｇ／ｋｇ 显著改善玉米－豆粕组．１０％麦麸和６％菜籽粕组肉鸡组织锰利用（Ｐ＜０．０５或Ｐ＜０．０１）,但对１０％米糠组需补加蛋氨酸锰１２０ｍｇ／ｋｇ才能显著改善肉鸡组织锰利用（Ｐ＜０．０５或Ｐ＜０．０１）。该项研究表明,麦麸、米糠及菜籽粕中植酸和中性洗涤纤维（ＮＤＦ）可能是肉鸡组织锰利用的主要限制因素,适宜补加蛋氨酸锰可改善肉鸡组织锰利用。     

不同营养水平对彭泽鲫春片鱼种生长影响的研究

采用Ｌ９（３４）正交设计法,配制九种不同能量、蛋白质、有效磷水平的配合饲料喂养彭泽鲫春片鱼种,测定鱼体的增重。试验结果为：第１－９组的日增重分别为２４９、２２８、１８３、２１４、２１９、１８７、３１１、３１０和２６７ｇ,日增重率分别为０７６％、０７０％、０５６％、０６７％、０６５％、０５６％、０９１％、０９１％和０８６％,相对增重率分别为３３６３％、３０７７％、２３５５％、２９０７％、２８３０％、２３１６％、４１８７％、４１９１％和３６０９％。结果表明：对彭泽鲫春片鱼种的生长影响的因素的重要性为能量＞蛋白质＞有效磷。彭泽鲫春片鱼种的配合饲料中能量的适宜量为２９Ｍｃａｌ／ｋｇ,蛋白质的适宜量为３０％,有效磷的适宜量为１２％。日粮配方及营养组合以第８组合最优。     

Growth and Feed Utilization of Captive Wild Subadult Black Sea Bass Centropristis striata Fed Practical Diets in a Recirculating System

The effects of four practical diets on growth, feed utilization, and body composition of wild‐caught juvenile and subadult black sea bass Centropristis striata (316 ± 113 g =±± SD) were compared for 221 d in a recirculating tank system consisting of 12 2,660‐L tanks. Salinity averaged 33.5 ppt and temperature averaged 20.9 C but vaned from 12 to 27.1 C. Diets differed in crude protein (CP) and crude lipid (CL) as follows: 1) low CP (44.0%), low CL (11.4%) trout diet; 2) low CP (44.8%), high CL (15.0%) trout diet; 3) midlevel CP (47.9%), midlevel CL (12.8%) Bounder diet; and 4) high CP (53.9%), high CL (15.1%) marine finfish diet. Energy: protein ratios (E: P) were 44.6, 45.3, 41.8, and 39.1 W/g. Survival to 221 d on all diets was 100%. Significant (P < 0.05) differences in growth rates were observed among diets. Final weights were higher for midlevel and high CP diets 3 and 4 (1,051 and 1,013 g) than for low CP diet 1 (873 g). Relative growth rate (RGR, % total increase in weight), specific growth rate (SGR, % increase in body weight/d), and daily weight gain (DWG, g/d) were higher for higher CP diets 3 and 4 (RGR = 223 and 221; SGR = 0.53; DWG = 3.28 and 3.16), than for low CP diet 1 (RGR = 181; SGR = 0.47; DWG = 2.54). There were no significant differences between initial and final whole body protein and fiber content among diets. Lipid and gross energy levels significantly increased (P < 0.0001) in all treatments while moisture levels significantly decreased (P < 0.001). Although these differences were not significant, feed conversion ratio (FCR = dry weight fed/wet weight gain) was lower for fish given midlevel CP diet 3 (1.49) and high CP diet 4 (1.52) than for those fed low CP diets 1 and 2 (1.60 and 1.62). Protein efficiency ratios (PER = weight gain/weight protein fed) (1.43 to 1.24), apparent net protein retention (ANPR = weight protein gain/weight protein fed) (20 to 25%), and apparent net energy retention (ANER = energy gain/energy fed) (53.3 to 56.8%) were not significantly different among treatments. The midlevel CP (50%), midlevel CL (12%) diet maximized growth rates and was also significantly less expensive per kg fish weight produced ($1.40) than the high CP diet ($1.94) which produced the second highest growth rates. These results demonstrated that wild‐caught black sea bass can be successfully reared in recirculating tanks from juvenile to marketable sizes with high survival and with good feed conversion and growth on commercially prepared diets with a wide range of protein and lipid levels.     

芽孢杆菌对斑节对虾饲料表观消化率的影响

研究了斑节对虾(Penaeus monodon)饲料中添加不同剂量的芽孢杆菌制剂(Bacillus sp.,109 CFU/g)对饲料干物质、粗蛋白、脂肪、磷、氨基酸和脂肪酸的表观消化率的影响.饲料1(对照组)、饲料2、饲料3、饲料4、饲料5和饲料6中芽孢杆菌制剂的添加量分别为0、1.0 g/kg、2.0 g/kg、3.0 g/kg、4.0 g/kg和5.0 g/kg饲料.养殖实验在室外水泥池进行,每池养虾40尾,每组实验设3个重复.以Y2O3为指示剂,添加量为0.01%,连续收集粪便20 d.6个实验组中,对饲料中各营养素的表观消化率分别为:干物质,74.35%～77.89%;粗蛋白,87.29%～89.01%;脂肪,86.46%～89.67%;磷,35.83%～44.17%;必需氨基酸,93.01%～94.04%;非必需氨基酸,91.05%～92.42%;饱和脂肪酸,86.88%～89.95%;单不饱和脂肪酸,90.39%～93.40%;多不饱和脂肪酸 高不饱和脂肪酸,87.97%～91.32%.对照组的脂肪表观消化率高于饲料2、饲料5和饲料6组,但低于饲料3和饲料4组.饲料3组的脂肪和部分脂肪酸的表观消化率最高.对照组的干物质、粗蛋白、氨基酸和磷的表观消化率最低,芽孢杆菌添加量在1.0～3.0 g/kg饲料范围内,随着芽孢杆菌添加量的增加,表观消化率逐渐上升,饲料4组的表观消化率最高,与其他组相比差异显著(P＜0.05),添加量超过3.0 g/kg的各组,随着芽孢杆菌添加量的增加,表观消化率又逐渐下降.实验结果表明,在饲料中添加适量的芽孢杆菌可以显著的提高干物质、粗蛋白、氨基酸和磷的表观消化率.     

奇可利和紫花苜蓿对新西兰白兔生产性能影响的研究

选取35日龄和45日龄的断奶新西兰白兔各24只,分别随机分为3组,每组8只。对照组只喂精料,试验I组用紫花苜蓿代替20%基础日粮,试验II组用奇可利代替20%基础日粮,比较这3组试验兔的增重、日增重、生长速度、料重比,分析比较2种牧草的经济效益。结果显示:试验期内试验I组日增重分别为36.88、37.18g,试验II组日增重分别为35.40、35.65g,对照组日增重分别为33.63、34.39g,试验I组、试验II组和对照组肉兔的只均增重和日增重均存在极显著差异(P<0.01);但试验I组的料重比分别比对照组下降4.60%、4.68%,试验II组的料重比分别比对照组下降9.51%、9.06%;试验II组比试验I组和对照组的只均获利高,经济效益好。由此可见,用奇可利和紫花苜蓿代替部分精饲料是可行的。     

不同养殖条件下黄缘闭壳龟二龄幼龟的生长研究

研究了常温养殖(气温为14.7～33.3℃)与初夏、秋末阶段性的控温养殖(气温为20.3 ～33.3℃)两种养殖方式下黄缘闭壳龟Cuora flavomarginata(Gray)二龄幼龟生长的情况,试验结果:通过180 d的试验,常温养殖幼龟平均增重54.27 g,体重相对增长率为115.89％,绝对增长率为0.30...     

Dietary protein requirement of juvenile kelp grouper (Epinephelus moara)

Dietary protein requirement of juvenile kelp grouper Epinephelus moara was investigated through a feeding trial. Experimental diets with graded crude protein (CP) levels (33.01%, 38.54%, 45.21%, 50.71%, 56.10% and 63.09% of dry matter respectively) were formulated. Six triplicate groups of fish (20 individuals per replicate with initial mean weight 6.00 g) were fed with each diet for 8 weeks. Best growth performance of fish was detected in 56.10% CP diet. The specific growth rate (SGR) significantly elevated with increasing dietary CP level to 50.71%, but there was no significant difference thereafter (p < .05). The feed conversion ratio (FCR) decreased significantly with dietary CP levels from 33.01% to 56.10% (p < .05). Glucose (GLU) and total protein (TP) concentrations in plasma had an increasing trend with dietary protein increasing. In the 33.01% CP group, plasma triglyceride (TG) content was significantly higher (1.67 mmol/L) than that in other dietary treatments (0.65–1.14 mmol/L). The lowest alanine transaminase (ALT) activity was observed in the 56.10% CP group (163.16 U/L). Crude lipid content in the muscle and liver was significantly elevated with increasing dietary protein levels (p < .05). The glycogen content in the liver decreased significantly as CP levels increased (p < .05). The fish fed diet with higher CP level (56.10% and 63.09%) had significantly higher energy retention (ER) and lipid retention (LR) than other treatments. Based on the broken‐line regression analysis of SGR and FCR, the optimal dietary protein requirement for juvenile kelp grouper is 54.61%–56.22%.     

鳖组织浆对鼠免疫功能的影响

从体内抑制试验和体外培养巨噬细胞的杀瘤试验对甲鱼组织浆的抑瘤作用进行了研究。体内抑瘤试验采用组织浆灌胃方式,计算抑瘤率和生命延长率。体外试验将巨噬细胞与肿瘤细胞共培养,测定ＮＯ浓度与细胞毒效应。培养上清液中一氧化氮（ＮＯ）浓度采用ＮＯ试剂盒检测,细胞毒效应通过ＭＴＴ比色法检测。用黄嘌呤氧化酶法测定用鳖组织浆大鼠脑、肝、血中的超氧化物歧化酶（ＳＯＤ）含量。结果表明,不同来源鳖的效果有区别,野生鳖和仿生养殖鳖２龄与４龄对Ｓ１８０小鼠肿瘤生长有明显的抑制作用（Ｐ〈０．０１）,其抑瘤率分别达７０．６９％和６３．１７％,荷瘤小鼠的生长延长率均显著高于空白对照组（Ｐ〈０．０１）,分别为４０．５９％和３９．９５％;１龄和２龄温室鳖的抑瘤效果也显著（Ｐ〈０．０５）。不同来源和不同年龄的鳖组织抑瘤效果有差异,野生鳖、仿生鳖和温室     

Predicting the optimal dietary essential amino acid profile for growth of juvenile yellow perch with whole body amino acid concentrations

Rapid methods of estimating dietary essential amino acid (EAA) requirements might facilitate increases in aquaculture production, particularly for new or emerging industries. We conducted a 12‐week feeding study to test the hypothesis that whole body EAA concentrations and the quantified methionine requirement could be used to predict the remaining dietary EAA requirements for juvenile all‐female yellow perch. Six purified diets were developed and fed to triplicate groups of fish for 12 weeks. The diets contained the EAA profile of fishmeal (FM), the profile as predicted by whole body analysis, the quantified methionine requirement and resulting A/E ratios (PRED), PRED + 20% of all EAA (PRED20), PRED + 40% of all EAA (PRED40), PRED + 20% threonine, isoleucine and tryptophan (PRED320), and PRED + 40% threonine, isoleucine and typtophan (PRED340). Mean weight gain and feed consumption were significantly higher in fish fed PRED20 (35.7 ± 3.2 and 55.0 ± 5.3 g, respectively) than in fish fed FSM (25.1 ± 0.4 g wt gain, 41.0 ± 1.9 g cons), PRED (23.4 ± 2.3 g wt gain, 40.1 ± 4.2 g cons) and PRED340 (22.9 ± 3.3 g wt gain, 35.0 ± 3.8 g cons). There was no significant difference in feed efficiency among treatments. We recommend an EAA profile similar to PRED20 for feeding all‐female juvenile yellow perch.     

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.     

Influence of dietary fat and carbohydrate levels on growth and body composition of rainbow trout Oncorhynchus mykiss under self-feeding conditions

SUMMARY: An 8-week feeding experiment was conducted to examine the influence of fat and carbohydrate levels in a 40% protein level diet on growth and body composition of rainbow trout Oncorhynchus mykiss under self-feeding conditions. Five fish meal-based diets were prepared to include gelatinized potato starch at four levels (9, 18, 27, and 36%) and dextrin (34%). Dietary fat levels were isoenergetically reduced from 18 to 7% by the digestible carbohydrates. Each diet was fed to four replicate groups (28 g/fish, 20–23 fish/group) using self-feeders. Specific growth rate, percentage weight gain and percentage protein retention did not differ between the treatments. Feed efficiency and protein efficiency ratios were higher in the 18% starch (s18) and s27 diet groups, and decreased in higher fat or carbohydrate diet groups. Although gross energy intake (kJ/kg BW per day) decreased as the starch level increased, levels of digestible energy intake did not differ between the treatments. Fat levels in the carcass, viscera and liver decreased as dietary carbohydrate level increased. These results suggest that a 40% protein diet with either 15% fat and 18% starch or 11% fat and 27% starch is appropriate for juvenile rainbow trout under self-feeding conditions.     

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.