不同蛋白水解物对花鲈(Lateolabrax japonicus)生长性能及非特异性免疫的影响

实验以基础饲料组[含30％鱼粉蛋白(FM)]为对照组,用鱼蛋白水解物(FPH)、猪血蛋白水解物(PBPH)、酵母蛋白水解物(YPH)和豆粕蛋白水解物(SPH)分别替代配方中10％的鱼粉蛋白,配制成5组等氮等脂的饲料,喂养初始平均体重为31.99 g的花鲈(Lateolabrax japonicus)8周,探讨饲料中不同蛋白水解物对花鲈生长、饲料利用、体组成成分及非特异性免疫的影响.结果显示:各处理组实验鱼存活率在97.78％-98.89％之间,没有显著性差异(P＞0.05);FPH组与FM组的末重和特定生长率最高,两者之间没有显著差异(P＞0.05),但显著高于PBPH组、SPH组和YPH组(P＜0.05);FPH组饲料效率高于FM组、PBPH组和YPH组(P＞0.05),且显著高于SPH组(P＜0.05);各实验处理组鲈鱼摄食率没有显著差异(P＞0.05);FPH组蛋白效率比显著高于FM组、PBPH组、SPH组和YPH组(P＜0.05);FPH组、FM组和YPH组的蛋白质沉积率显著高于PBPH组和SPH组(P＜0.05).饲料中添加FPH和YPH会显著增加花鲈肝脏和血清中碱性磷酸酶、酸性磷酸酶、超氧化物歧化酶、溶菌酶活性和总抗氧化能力,显著高于FM组、PBPH组和SPH组(P＜0.05).FPH组的花鲈鱼体粗蛋白含量高于FM组和YPH组,但差异不显著(P＞0.05),FPH组显著高于PBPH组和SPH组(P＜0.05).综上所述,4种不同蛋白水解物替代鱼粉后投喂花鲈幼鱼,鱼蛋白水解物效果最好,其次是酵母蛋白水解物、猪血蛋白水解物和豆粕蛋白水解物.     

Effect of dietary carbohydrate level on growth performance,body composition,apparent digestibility coefficient and digestive enzyme activities of juvenile cobia,Rachycentron canadum L

A 9‐week feeding trial was conducted to investigate the effect of dietary carbohydrate level on the growth performance, body composition and apparent digestibility coefficient and digestive enzyme activities of juvenile cobia. Six isonitrogenous and isolipidic diets containing graded levels of starch (1.3%, 6.5%, 12.5%, 18.4%, 24.2% and 30.4%) were fed to juvenile cobia. Specific growth rate (SGR), feed efficiency ratio (FER) and protein efficiency ratio (PER) increased with increasing dietary starch up to 18.4% (P<0.05), and thereafter SGR declined but FER and PER remained nearly the same. Apparent digestibility coefficient of starch reduced significantly when dietary starch up to 30.4%. Fish fed the diets with starch from 18.4% to 30.4% showed higher amylase activities in intestinal tract than those fed diets containing starch 1.3% and 6.5% (P<0.05). Significantly higher whole‐body lipid contents were observed in fish fed the diets containing higher starch. Whole‐body moisture content was inversely correlated with whole‐body lipid content, while protein and ash showed no significant differences. Plasma glucose, hepatosomatic index, liver glycogen and liver lipid increased with an increasing dietary starch. Based on SGR and FER, the appropriate dietary starch supplementations of juvenile cobia were estimated to be 21.1% and 18.0 % of diet respectively.     

Taurine alone or in combination with fish protein hydrolysate affects growth performance,taurine transport and metabolism in juvenile turbot (Scophthalmus maximus L.)

The study was conducted to investigate the effects of taurine (Tau) alone or in combination with fish protein hydrolysate (FPH) on growth performance, the expression of Tau transporter (TauT) and metabolic profile in juvenile turbot. FM, FPH0, FPH0+T, FPH10 and FPH10+T diets, respectively, contained 300, 150, 150, 80, and 80 g/kg fishmeal. FPH10 and FPH10+T diets contained 62 g/kg FPH. FPH0+T and FPH10+T diets were, respectively, prepared by supplementing the FPH0 and FPH10 diet formulations with 8 g/kg Tau. Specific growth rate was the highest in FM group and the lowest in FPH10 group. TauT mRNA levels in fish fed Tau supplemented diets were significantly lower than that in Tau unsupplemented diets. NMR‐based metabolomics analysis showed that Tau contents in liver of FPH0+T and FPH10+T were significantly higher than that of FM, FPH0 and FPH10. In muscle, Tau contents were significantly decreased in the FPH10+T versus FPH0 and the FPH10+T versus FPH10 comparisons. In conclusion, 62 g/kg FPH to replace fishmeal may not affect Tau synthesis, transport and metabolism. However, Tau supplemented alone or in combination with a certain level of FPH could reduce the requirement for Tau synthesis and transport and increased Tau levels in muscle and liver.     

江蓠、浒苔、藻渣和菌渣替代鱼粉对红鳍东方鲀幼鱼生长性能、相关生化指标的影响

本实验旨在研究江蓠(Gracilaria verrucosa)、浒苔(Enteromorpha prolifera)、藻渣和菌渣替代鱼粉对红鳍东方鲀(Takifugu rubripes)幼鱼生长性能、血清和肝脏生化指标和体组成的影响。实验共制成6种等氮、等脂的饲料,以含鱼粉60%为对照组1和45%鱼粉的为对照组2,分别将10%的江蓠、浒苔、藻渣、菌渣与植物蛋白质配合后替代对照组1饲料中30%的鱼粉,投喂初始体重为(17.33±0.55) g的红鳍东方鲀幼鱼56 d。结果显示,1)浒苔组特定生长率(SGR)显著高于其他5组(P<0.05),藻渣组SGR显著高于对照组2和江蓠组(P<0.05),与对照组1和菌渣组无显著差异(P>0.05);对照组1和浒苔组饲料效率(FER)显著高于对照组2和菌渣(P<0.05),与江蓠和藻渣组无显著差异(P>0.05);对照组1的蛋白质沉积率(PPV)和蛋白质效率(PER)显著高于对照组2和菌渣组(P<0.05),与江蓠、浒苔和藻渣组无显著差异(P>0.05)。2)各组血清和肝脏中谷丙转氨酶(GPT)和谷草转氨酶(GOT)活性均无显著差异(P>0.05)。各组血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性均无显著差异(P>0.05)。3)菌渣组鱼体粗蛋白质含量显著高于藻渣组(P<0.05),与对照组1、对照组2、江蓠和浒苔无显著差异(P>0.05);浒苔和藻渣组鱼体粗脂肪含量显著高于对照组2 (P<0.05),与对照组1、江蓠和菌渣组无显著差异(P>0.05)。综合来看,将10%江蓠、浒苔、藻渣和菌渣与植物蛋白质配合后替代饲料中30%的鱼粉对红鳍东方鲀幼鱼的生长性能无不良影响,并且浒苔可以显著提高红鳍东方鲀的生长性能。     

日粮中鱼蛋白水解物对黄颡鱼生长、体成分和血清生理指标的影响

为了探讨鱼蛋白水解物对黄颡鱼生产性能的影响,以日本鳀粉为对照,以实用型黄颡鱼饲料配方模式为基础开展实验:1以30.5%鱼粉为对照(FM),在相同配方模式下,以6%鱼蛋白水解物(MPH6)替代20%的鱼粉;2以30.5%鱼粉为对照(FM),在无鱼粉日粮中分别添加3%(FPH3)、6%(FPH6)、12%(FPH12)鱼蛋白水解物;共设计5组等氮等能实验日粮,在池塘网箱中养殖黄颡鱼[初始体质量(30.08±0.35)g]60 d。结果显示:与FM相比,FPH12在SGR、FCR、PRR和FRR方面均无显著差异,而MPH6、FPH3、FPH6组SGR降低了15.45%~24.39%,FCR升高了32.14%~42.86%,MPH6、FPH6差异显著,在PRR和FRR方面,MPH6、FPH3、FPH6组PRR降低了21.11%~27.78%,MPH6组FRR降低了41.51%;全鱼水分、粗蛋白、粗脂肪和灰分各组间差异不显著,FPH3、FPH6、FPH12肌肉多种游离氨基酸水平显著高于FM,其中Thr、Val、His与其在日粮中的水平显著相关;FPH6组HSI显著低于FM,鱼蛋白水解物对CP、VSI、肠体比的影响不显著;血清AST、ALT、HDL、LDL、TP、CHOL、TG无显著差异,FPH3组ALB显著低于FM。研究表明:黄颡鱼日粮中,12%鱼蛋白水解物(干物质)与30.5%鱼粉在生长速度、饲料效率、血清生理指标等方面具有一定的等效性;过高的植物蛋白日粮影响了黄颡鱼的生产性能;饲喂鱼蛋白水解物日粮使黄颡鱼肌肉游离氨基酸的含量升高,特别是呈味氨基酸的含量增加。     

Peptide molecular weight distribution of soluble protein fraction affects growth performance and quality in European sea bass (Dicentrarchus labrax) larvae

Dicentrarchus labrax were fed from 10 to 40 days posthatching with six microdiets differing in the inclusion level (60 g kg^‐1 and 120 g kg^‐1) and type of protein hydrolysate (PH; yeast, YPH; pig blood, PBPH; pig red blood cells, PRBCPH). A microdiet containing 120 g kg^‐1 fish PH (FPH) was used as a control. PH differed in their amino acid (AA) profile and molecular weight distribution and therefore the tested microdiets too. The estimated content in FAA and di‐ and tripeptides in the FPH microdiet was 2 g kg^‐1 and 44 g kg^‐1, respectively. FAA estimated levels in YPH and PBPH microdiets were 26 g kg^‐1 and 53 g kg^‐1, whereas levels of di‐ and tripeptides were 30 g kg^‐1 and 60 g kg^‐1, respectively. The estimated levels of FAA in PRBCPH microdiets were 8 g kg^‐1 and 17 g kg^‐1, whereas estimated levels of di‐ and tripeptides were 11 g kg^‐1 and 22 g kg^‐1, respectively. Results revealed that FPH may be replaced by alternative PH from yeast and pig blood products, as fish fed those diets performed, in terms of growth, survival, digestive function and incidence of skeletal deformities, as well as those fed the FPH microdiet. Using YPH, PBPH and PRBCPH, the inclusion level of PH in microdiets might be reduced to a half with respect to current practices using FPH.     

Evaluation of Cluster Bean Meal Cyamposis fefrugonoloba as a Dietary Protein Source for Common Carp Cyprinus carpio L.

Abstract— A12-wk feeding experiment was conducted to study the feasibility of utilizing cluster bean seed meal (CBM) as a replacement for fishmeal in the diets for common carp Cyprnus carpio fingerlings. The replacement levels of cluster bean meal protein in the diets were 25, 50, 75, and 100% of the total fishmeal protein. All diets were isonitrogenous at 33.1% crude protein and isocaloric at 4.8 Kcal/g. There were significant differences in the final individual weights, weight gains, specific growth rates (SGR %/d), feed conversion ratios (FCR), feed efficiency ratio (FER), protein efficiency ratios (PER), and feed intake among fish group ( P × 0.05). Common carp fed the diet containing 50% (CBM) exhibited comparable growth to those fed a fishmeal-based diet. Digestibility of protein, energy and lipid decreased with increasing levels of CBM above 50% of total fishmeal replacement in the diet. Incorporation of CBM in diets significantly affected the dry matter, protein, and energy of whole fish body. These results suggest that CBM can replace 50% of the fishmeal in diet for common carp.     

紫花苜蓿浓缩叶蛋白替代鱼粉对星斑川鲽幼鱼生长、体组成及血液生化指标的影响

研究了紫花苜蓿浓缩叶蛋白替代0%(S0)、10%(S10)、20%(S20)、30%(S30)、40%(S40)、50%(S50)的鱼粉蛋白对星斑川鲽(Platichthys stellatus)幼鱼生长、体组成及血液生化指标的影响。实验幼鱼体质量(83.0±0.20)g。结果显示:1)当替代比例≤20%时,各组间星斑川鲽幼鱼特定生长率(SGR)、日摄食率(DFI)、饲料效率(FE)和蛋白质效率(PER)均无显著变化,高于此值时呈显著下降(P<0.05)。随饲料中紫花苜蓿浓缩叶蛋白替代鱼粉比例的升高,鱼体肥满度(CF)呈显著下降趋势(P<0.05),而消化道指数(DTI)则呈显著上升趋势(P<0.05);各实验组干物质、蛋白质及脂肪表观消化率均呈直线下降趋势(P<0.05)。以星斑川鲽幼鱼特定生长率(SGR)为参考指标,采用折线回归分析得出,在本实验条件下,星斑川鲽幼鱼获得最佳生长时紫花苜蓿浓缩叶蛋白替代鱼粉蛋白的适宜比例为19.0%。2)紫花苜蓿浓缩叶蛋白替代鱼粉对星斑川鲽幼鱼肌肉水分、蛋白及粗灰分含量未产生显著性影响,肌肉脂肪含量仅S40组显著低于S0和S20组,其他各组间无显著差异;当替代比例小于20%时,肝脏水分呈显著上升趋势(P<0.05),之后趋于平稳(P>0.05)。肝脏粗脂肪变化趋势与此相反。肝脏粗蛋白含量仅表现为S30、S50组显著高于S0组(P<0.05),其他各组无显著差异(P>0.05)。肝脏粗灰分含量不受饲料鱼粉替代比例的影响(P>0.05);全鱼水分呈显著上升趋势(P<0.05),而粗脂肪含量呈显著下降(P<0.05)。S30组全鱼粗蛋白最高,S40组最低(P>0.05),除S30组外,其他各组均与S0组间无显著性差异(P>0.05)。各组间全鱼粗灰分含量变化不显著(P>0.05)。3)当替代比例>20%时,星斑川鲽幼鱼血浆甘油三酯(TG)含量呈显著降低。各组间胆固醇(CHO)含量随紫花苜蓿浓缩叶蛋白的添加呈直线下降趋势(P<0.05)。当替代比例≥20%时,碱性磷酸酶(ALP)活性有下降趋势(P<0.05)。当替代比例分别大于20%和40%时,谷草转氨酶(AST)和谷丙转氨酶(ALT)活性显著升高但各组间差异不显著(P>0.05)。实验鱼血浆溶菌酶(LSZ)活力随鱼粉替代比例的升高呈显著上升(P<0.05)。各实验组间血浆丙二醛(MDA)含量无显著差异,但均低于S0组(P<0.05),超氧化物歧化酶(SOD)活性不受紫花苜蓿浓缩叶蛋白替代鱼粉比例的影响(P>0.05)。结论认为,在本实验条件下,星斑川鲽幼鱼获得最佳生长时紫花苜蓿浓缩叶蛋白替代鱼粉蛋白的适宜比例为19.0%。     

1H NMR‐based metabolomics studies on the effect of size‐fractionated fish protein hydrolysate,fish meal and plant protein in diet for juvenile turbot (Scophthalmus maximus L.)

This study was designed to evaluate changes in the metabolic profile of liver and muscle of turbot (Scophthalmus maximus L.) fed fishmeal‐based diet, diets containing size‐fractionated fish protein hydrolysate and plant protein‐based diet using ¹H NMR‐based metabolomics approach combined with the growth. Fish protein hydrolysate (FPH) was obtained by enzymatic treatment, permeate fraction was obtained as UF by ultrafiltered step, and retentate fraction was retained as RF. FM diet contained fish meal used as a single protein source. Four other diets (PP, UF, FPH and RF) contained 180 g kg^?1 diet fish meal. 54, 55 and 55 g kg^?1 dry diet UF, FPH and RF were supplemented to UF, FPH and RF diets. All diets were formulated to be isolipidic and isonitrogenous fed to five triplicate groups of turbot (16.05 ± 0.03 g) for 68 days. O‐PLS‐DA in FM versus UF, FM versus FPH, FM versus RF and FM versus PP resulted in a reliable model for muscle and liver tissue, while O‐PLS‐DA in UF versus FPH and UF versus RF only showed metabolites changes in liver tissue. Results indicated that metabolite changes among the different treatments were consistent with the growth tendency.     

The effect of the dietary substitution of fishmeal with tuna by‐product meal on growth,body composition,plasma chemistry and amino acid profiles of juvenile Korean rockfish (Sebastes schlegeli)

The effect of the substitution of fishmeal with tuna by‐product meal (TBM) in the diet of Korean rockfish on growth, body composition, plasma chemistry and amino acid profiles was determined. Nine experimental diets were prepared. The control (Con) diet consisted of 550 g kg^?1 fishmeal. The 10, 20, 30, 40, 60, 80 and 100 % fishmeal diets were substituted with tuna by‐product meal (TBM), referred to as the TBM10, TBM20, TBM30, TBM40, TBM60, TBM80 and TBM100 diets, respectively. Finally, the fishmeal and soybean meal was completely replaced with TBM in the diet TBM100‐S. There was no significant difference in weight gain and SGR of the fish that were fed the TBM40 and Con diets. The feed conversion ratio (FCR) of the fish that were fed the Con, TBM10, TBM20 and TBM30 diets was lower than that of the fish that were fed all of the other diets. The protein efficiency ratio (PER) of fish that were fed the TBM10, TBM20 and TBM300 diets was higher than that of fish that were fed the TBM40, TBM60, TBM80, TBM100 and TBM100‐S diets. It can be concluded that the substitution of fishmeal with up to 40 and 30 % TBM in the diet of juvenile Korean rockfish could be made without exerting a detrimental effect on their growth (SGR) and feed utilization (FCR and PER), respectively.     

Dietary protein requirement of juvenile obscure puffer,Takifugu obscurus

A 10‐week feeding experiment was conducted to determine the optimum dietary protein requirement of juvenile obscure puffer (Takifugu obscurus). Six isoenergetic (20 MJ kg^?1 gross energy) diets were formulated to contain graded levels of 34%, 38%, 42%, 46%, 50% or 54% crude protein (as dry matter basis). The results showed final body weight, weight gain and specific growth rate (SGR) increased significantly with increasing protein levels up to 42% and then decreased thereafer. Second‐order polynomial regression analysis (y = ?0.0024x² + 0.1788x ? 1.3196, R² = 0.9032) indicated a maximum SGR at protein level of 37%. Feed conversion ratio (FCR) decreased with increasing levels of dietary protein up to 42% and increased thereafter. Second‐order polynomial regression analysis (y = 0.0054x² ? 0.4351x + 10.391, R² = 0.753) indicated a minimum FCR at protein level of 40%. Protein efficiency ratio (PER) of fish fed the 34%, 38% and 42% diets was significantly higher than that of fish fed the 46%, 50% and 54% diets, and broken‐line analysis indicated PER tended to decrease when dietary protein level was higher than 40%. Generally, whole body lipid content, total cholesterol, low‐density lipoprotein cholesterol and triacylglycerol decreased with increasing levels of dietary protein. Fish fed the 42% protein diet showed the highest essential amino acids (histidine, isoleucine, leucine, lysine and threonine) and non‐essential amino acids (aspartic acid and glutamic acid) in muscle. Based on the second‐degree polynomial regression analysis of SGR and FCR and broken‐line analysis of PER, the optimal dietary protein level of obscure puffer is estimated to be between 37% and 40% (% as dry matter basis).     

Fish protein hydrolysate affected amino acid absorption and related gene expressions of IGF‐1/AKT pathways in turbot (Scophthalmus maximus)

The effects of fish protein hydrolysate (FPH) on growth, peptide and amino acid (AA) transporters, postprandial free AA and related gene expression of IGF‐1/AKT pathway were evaluated in turbot (Scophthalmus maximus). Three diets were formulated to contain the same low level of fishmeal; meanwhile 0, 45 and 180 g/kg FPH were, respectively, supplemented to the FF (FPH‐free), FL (FPH‐Low) and FH (FPH‐High) diets. Fish fed the FH diet improved the growth compared with the other groups. For peptide and AA transporters, PepT1, B⁰AT1, CAT1 and PAT1 mRNA levels in proximal or distal intestine decreased in fish fed the FH diet. The concentration of free total essential AAs in serum was higher in the FH treatment than that in the FF treatment at 2 and 6 hr after feeding. For IGF‐1/AKT pathway in muscle, IGF‐1, 4E‐BP1 and FoxO1 mRNA levels were the highest in the FH group, whereas IGF‐1R mRNA levels were the highest expression level in the FF group. In conclusion, down‐regulated AAs transport, alleviated the delayed postprandial peak of serum‐free AAs and increased muscle protein synthesis were observed to improve the growth when turbot was fed high FPH level diets containing a high plant protein.     

大菱鲆利用水解鱼蛋白和牛蛙蛋白的差异

为探究大菱鲆对不同来源水解蛋白的利用效率,实验选取太平洋狭鳕和牛蛙下脚料为蛋白来源,分别制备水解鱼蛋白和水解牛蛙蛋白,以初始体重为(8.00±0.01) g的大菱鲆为研究对象,进行为期56 d的养殖实验。实验设2个对照组,正对照组(PC)鱼粉含量为35.0%,负对照组(NC)鱼粉含量为26.5%;设2个实验组,水解鱼组(FPH)为26.5%的鱼粉和8.0%的水解鱼蛋白,水解牛蛙组(BPH)为26.5%的鱼粉和9.5%的水解牛蛙蛋白。结果显示,FPH组的终末体重、增重率和特定生长率显著高于BPH组和NC组,与PC组无显著差异。摄食6 h后,食糜必需氨基酸中赖氨酸、精氨酸、苏氨酸和缬氨酸在BPH组的含量显著高于PC组;多数非必需氨基酸在BPH组含量最高,但无显著差异。质子偶联氨基酸转运载体PAT1和小肽转运载体PepT1的mRNA表达量分别在FPH组和BPH组都显著高于PC组和NC组;碱性氨基酸转运载体CAT1和y⁺L型氨基酸转运载体y⁺LAT2的mRNA表达量在各处理组中无显著差异。研究表明,在饲料中添加鳕和牛蛙蛋白水解物均能提高大菱鲆的生长性...     

Replacement of by-catch fishmeal with dried chicken viscera meal in extruded feeds: effect on growth,nutrient utilisation and carcass composition of catfish <Emphasis Type="Italic">Clarias batrachus</Emphasis> (Linn.) fingerlings

An 84-day feeding trial was conducted to study the effect of replacing dietary fishmeal with dried chicken viscera meal (CVM) on the growth (net biomass gain, specific growth rate, SGR), feed acceptability, feed conversion ratio (FCR), protein efficiency ratio (PER) and carcass composition of Clarias batrachus fingerlings. Triplicate groups of fingerlings with mean initial body weight of 13.35 g were fed on six iso-nitrogenous and iso-lipidic diets. The control diet (CVM0) used marine by-catch fishmeal as the sole source of animal protein. In the other five diets (CVM100–CVM500), 20–100% of fishmeal was substituted by dried CVM at 20% increments. The highest body weight gain, SGR and PER, and the lowest FCR were observed in fish fed a diet containing 300–500 g CVM kg⁻¹. The fish accumulated increasing quantities of lipids and decreasing levels of ash in their carcasses with increasing levels of dietary CVM.     

卵形鲳鲹幼鱼饲料中适宜蛋白能量比的研究

以鱼粉、豆粕为蛋白源,豆油、鱼油为脂肪源,配制9种不同蛋白能量水平的饲料,蛋白质3个水平(38%、43%、49%),每个蛋白水平设3个脂肪梯度(6%、10%、14%),其蛋白能量比为19.3～27.4mg/kJ。卵形鲳鲹初始质量为(25.02±0.16)g,每个处理设3个重复,每个网箱(1.5 m×1.0 m×2.0m)放养卵形鲳鲹苗20尾,养殖试验持续8周。结果显示,卵形鲳鲹特定生长率随饲料蛋白水平的升高而显著升高(P<0.05)。投喂含43%或49%蛋白质、6%脂肪饲料的卵形鲳鲹表现出较好的特定生长率。饲料中不同的脂肪水平未表现出蛋白质节约效应,较高的脂肪水平反而抑制了卵形鲳鲹的特定生长率、饲料效率和蛋白质效率。卵形鲳鲹鱼体蛋白和脂肪含量分别随饲料蛋白质和脂肪水平的上升而显著升高(P<0.05)。在该试验条件下,卵形鲳鲹幼鱼饲料中最适蛋白质、脂肪水平和蛋白能量比分别为43%、6%和24.4 mg/kJ。     

Fish protein hydrolysate in diets of turbot affects muscle fibre morphometry,and the expression of muscle growth‐related genes

The study was conducted to investigate the effects of fish protein hydrolysate (FPH) in diets for turbot on growth performance, muscle fibre morphometry, and the expression of muscle growth‐related genes. A control diet (FPH0) contained 0 g/kg FPH, and four experimental diets were formulated replacing fishmeal with FPH at levels of 45 (FPH4.5), 120 (FPH12), 180 (FPH18) and 300 (FPH30) g/kg. Fish fed the FPH12 and FPH18 diets had higher specific growth rate (SGR) than fish fed the FPH0 diet (p < .05), and a quadratic regression was found between SGR and dietary FPH level (p = .001, R² = .677). Cross‐section area (CSA) and the length of sarcomere in the FPH12 group increased compared with the control group (p < .05), and a quadratic regression was observed between CSA and dietary FPH level (p = .006, R² = .574) and between sarcomere length and dietary FPH level (p = .018, R² = .788). An appropriate level of FPH down‐regulated myostatin 2 gene expression and up‐regulated proliferating cell nuclear antigen gene expression, while the expression of myogenic regulatory factors was not affected by dietary treatments (p > .05). To conclude, an appropriate level of FPH may improve muscle growth by regulating the expression of muscle growth‐related genes, and muscle microstructure and ultrastructure.     

大豆浓缩蛋白替代鱼粉对大菱鲆摄食、生长及体组成的影响

研究了大豆浓缩蛋白(SPC)替代鱼粉对大菱鲆生长及生理生化指标的影响。5种饲料分别含有0、12.0%、25.0%、37.0%和49.5%的SPC以替代相应的鱼粉,并分别添加0、0.83%、1.65%、2.48%和3.30%的必需氨基酸混合物(L-lysine∶DL-methionine∶L-leucine∶Lvaline∶L-threonine=18∶6∶3∶2.5∶2)以平衡各组饲料的氨基酸组成。每种饲料投喂3个水族箱(300 L),每个水族箱放养实验鱼16尾,实验鱼初始体质量为(31.1±0.1)g。经过9周生长实验,结果显示随着饲料中SPC替代水平的升高,大菱鲆摄食率、特定生长率均显著下降(P0.001)。然而,当使用0~37.0%的SPC替代鱼粉时,各处理组饲料效率和蛋白质效率未出现显著差异(P0.05)。饲料中SPC替代鱼粉对大菱鲆鱼体水分、粗蛋白、粗脂肪及灰分含量均无显著影响(P0.05)。各处理组干物质和粗蛋白的表观消化率之间也未出现显著差异(P0.05)。研究表明,在本实验条件下SPC不能作为大菱鲆饲料中替代鱼粉的有效蛋白源,造成SPC替代效果较差的主要原因是其对大菱鲆饲料适口性的显著影响。     

Evaluation of feed utilization and growth performance of juvenile striped catfish Pangasianodon hypophthalmus fed diets with varying inclusion levels of corn gluten meal

A nutrition trial with striped catfish (Pangasianodon hypophthalmus) juveniles was undertaken to evaluate the effect of replacing dietary fishmeal (FM) protein with corn gluten meal (CGM). A diet with FM as the main protein source was used as the control diet (FM). Five experimental diets (approximately 320 g kg^?1 crude protein) were formulated to progressively replace 20% (CGM20), 40% (CGM40), 60% (CGM60), 80% (CGM80) and 100% (CGM100) of FM protein. Fifteen fish per tank (initial weight 11.2 ± 0.6 g) were randomly distributed into 18 80‐litre fibreglass tanks connected to a closed recirculation system (temperature 30.3 ± 1.0 °C). The diets were tested in triplicate for 12 weeks. The final weight and specific growth rate (SGR) of fish fed diets CGM20, CGM40 and CGM60 were not significantly different compared to fish fed the FM diet. Feed intake (FI) tended to decrease with increasing dietary CGM level. Striped catfish fed FM, CGM20 and CGM40 had significantly lower feed conversion ratio (FCR) compared with fish fed CGM80 and CGM100 (P < 0.05). The protein efficiency ratio (PER) of fish fed the CGM80 and CGM100 diets was significantly lower than those of all other treatments (P < 0.05). Total ammonia‐nitrogen (TAN) excretion increased with elevated dietary CGM inclusion. The viscerosomatic index (VSI) of fish fed the CGM80 and CGM100 diets were significantly higher (P < 0.05) than those of fish fed the other treatments. The crude lipid content in the final body composition of the striped catfish was elevated significantly with increasing dietary CGM levels. Fish fed the CGM80 and CGM100 diets displayed haematocrit levels significantly lower (P < 0.05) than those fed the other diets. The haemoglobin content in fish was significantly higher in fish fed CGM20 and lower at CGM100 compared to fish fed the FM diet. The results of the present trial indicated that the optimum level of FM protein replacement with CGM determined by quadratic regression analysis was 25.1% on the basis of maximum SGR.     

黄鳍鲷幼鱼对几种不同糖源的利用

本研究用来评价黄鳍鲷幼鱼对饲料中葡萄糖、麦芽糖、糊精、玉米淀粉和预糊化玉米淀粉的利用。本试验饲料为6种等氮(粗蛋白:45%,干重)等脂(粗脂肪:9%,干重)的半纯化饲料,其中对照组糖源为纤维素。每种饲料设3个平行。试验鱼初始体重为(3.57±0.13)g(平均值±均差)。试验鱼饲养在含18个水族箱的循环系统中。水温保持在(27±1)℃。试验周期为8周。本试验用来评价黄鳍鲷幼鱼对饲料中不同糖源利用的指标为生长指标、饲料效率、蛋白质效率和肝脏的6-磷酸葡萄糖脱氢酶、苹果酸脱氢酶、异柠檬酸脱氢酶和葡萄糖-6-磷酸脱氢酶。试验结果表明,黄鳍鲷幼鱼体增重、特定生长率、肝体比、肠系膜脂肪体比、饲料效率、蛋白质效率、肝脂肪合成有关酶活性和全鱼、肌肉、肝脏组成均受到饲料中不同糖源的显著影响。预糊化玉米淀粉和麦芽糖组比其它糖源组显著具有更好的体增重和特定生长率,但与对照组没有显著性差异。黄鳍鲷幼鱼生长和体增重与饲料中糖源的复杂性没有相关性。饲喂预糊化淀粉和对照饲料鱼的饲料效率和蛋白质效率显著比其它组高。饲料中糖的添加增加了黄鳍鲷幼鱼的肝体比,但对照组肝体比与糊精组,玉米淀粉组没有显著性差异。预糊化玉米淀粉组肠系膜脂肪体比比其它饲料组要高。结论:基于体增重和特定生长率为指标,饲料中添加25%预糊化玉米淀粉和麦芽糖可以提高黄鳍鲷幼鱼的生长。另外,玉米淀粉预糊化显著提高了黄鳍鲷对玉米淀粉的利用。     

Replacement of fishmeal by fish protein hydrolysate and biofloc in the diets of Litopenaeus vannamei postlarvae

This study aimed to evaluate the effect of the gradual replacement of fishmeal with fish protein hydrolysate (FPH) and biofloc flour (BF) in the diets of white shrimp Litopenaeus vannamei postlarvae (2 mg). Five diets (420 g kg^?1 of crude protein) were formulated, and these replaced 0 (control), 10, 20, 30 and 40% (T0, T10, T20, T30 and T40, respectively) of the fishmeal. A commercial diet was used as an external control. The alternative ingredients FPH and BF were added at a ratio of 1 : 1. After 42 days, the shrimp survival was higher than 99% in all the treatment groups. A regression test indicated that the ideal fishmeal substitution level to obtain optimal zootechnical parameters (final weight, weight gain and protein efficiency) is between 15.16 and 16.5%. In this study, we demonstrated that BF and FPH are potential ingredients that can be used to replace fishmeal in L. vannamei postlarvae diets.