稻田和池塘养殖禾花鲤肌肉营养与品质分析

为评估不同养殖环境对禾花鲤(Cyprinus carpio)肌肉营养与品质的影响,采用国标法检测稻田和池塘2种养殖环境下禾花鲤肌肉常规营养成分、质构特性、氨基酸和脂肪酸组成。结果显示,池塘组禾花鲤肌肉粗蛋白和粗脂肪含量显著高于稻田组(P<0.05),水分含量显著低于稻田组(P<0.05),灰分含量2组差异不显著(P>0.05);池塘组肌肉粘性显著高于稻田组(P<0.05),内聚性和剪切力显著低于稻田组(P<0.05),其他质构指标2组间差异不显著(P>0.05);肌肉氨基酸测定结果显示,池塘组氨基酸总量(?TAA)、鲜味氨基酸(DAA)、必需氨基酸(EAA)、非必需氨基酸(NEAA)显著高于稻田组(P<0.05),?EAA/TAA和?EAA/NEAA显著低于稻田组(P<0.05),2组禾花鲤必需氨基酸构成比例均符合FAO/WHO标准;在鲜味氨基酸含量方面,池塘组主要的4种呈味氨基酸含量均显著高于稻田组(P<0.05)。根据氨基酸评分(AAS)和化学评分(CS)标准,2组禾花鲤肌肉第一、二限制性氨基酸均分别为色氨酸(Trp)和缬氨酸(Val);在脂肪酸测定结果中显示,池塘组单不饱和脂肪酸(∑MUFA)含量显著高于稻田组(P<0.05),但多不饱和脂肪酸(∑PUFA)、EPA+DHA和∑n-3PUFA/ ∑n-6PUFA显著低于稻田组(P<0.05)。综上所述,池塘和稻田养殖条件下,禾花鲤均为优质的蛋白质来源,但不同养殖环境对禾花鲤肌肉营养与品质有显著影响。从常规营养成分、氨基酸评分方面看,池塘养殖条件下禾花鲤肌肉营养价值更高;从脂肪酸角度来看,稻田养殖禾花鲤肌肉具有较高的EPA+DHA含量以及n-3/n-6多不饱和脂肪酸比例,更适合高血脂和心血管疾病等患者食用,从质构性来看,稻田养殖环境下禾花鲤肌肉更具嚼劲。     

池塘两种养殖方式下草鱼的营养差异

为了解传统池塘养殖和池塘内循环系统养殖草鱼的营养差异,对2种养殖方式草鱼的营养成分及营养品质进行了比较研究。结果显示,池塘养殖草鱼肌肉水分、粗脂肪含量、脏体比以及pH降低值和滴水损失高于循环养殖系统的草鱼,而肌肉粗蛋白含量和抗氧化能力低于循环养殖系统的草鱼。池塘养殖和循环系统养殖草鱼肌肉必需氨基酸构成比例均符合FAO/WHO的标准,必需氨基酸均是赖氨酸(Lys)含量最高;池塘养殖草鱼氨基酸总量(∑TAA)、鲜味氨基酸总量(∑DAA)和甜味氨基酸总量(∑SAA)低于循环养殖系统;根据氨基酸评分(AAS)和化学评分(CS),2种模式的第一限制性氨基酸均为缬氨酸(Val)。循环养殖系统草鱼肌肉∑n-3PUFA和∑n-6PUFA含量显著低于池塘养殖,但肌肉EPA + DHA含量是池塘养殖的1.5倍。研究表明,草鱼营养组成合理,池塘内循环系统养殖的草鱼在营养成分及鲜甜味方面优于池塘养殖。     

网箱与微流水养殖的齐口裂腹鱼肌肉营养成分的比较与分析

本研究比较和分析网箱与微流水两种养殖模式下体质量(76.5±17.8)g和(67.2±8.1)g的齐口裂腹鱼Schizothorax prenanti肌肉常规营养成分。结果显示:两组齐口裂腹鱼肌肉中一般营养成分含量不存在显著性差异,均含有18种氨基酸;除色氨酸(Trp)和组氨酸(His)外,网箱组齐口裂腹鱼肌肉中其余氨基酸、氨基酸总量、必需氨基酸总量和鲜味氨基酸总量均显著低于微流水组。氨基酸评分(AAS)和化学评分(CS)结果显示:两组齐口裂腹鱼肌肉中必需氨基酸构成合理,色氨酸均为第一限制性氨基酸,赖氨酸在必需氨基酸中评分最高。两组齐口裂腹鱼肌肉中均含有21种脂肪酸,网箱组饱和脂肪酸(SFA)总量和单不饱和脂肪酸(MUFA)含量显著低于微流水组,而多不饱和脂肪酸(PUFA)含量显著高于微流水组,且n-3/n-6比值要高于网箱组。综上所述,微流水养殖的齐口裂腹鱼营养价值更高。     

红和黑肌肉营养成分的比较分析

本研究利用常规生化和物理分析方法对红色斑点叉尾(Red Ictalurus punctatus)(简称红)和黑色斑点叉尾(Black Ictalurus punctatus)(简称黑)背部肌肉一般营养成分、质构特性、氨基酸和脂肪酸含量进行了分析,并对其营养价值进行了评价。结果显示:黑水分显著高于红,粗脂肪含量显著低于红。红肌肉咀嚼性显著高于黑。红和黑的氨基酸组成基本一致,均含有18种氨基酸(除色氨酸),总含量占鲜肉的15.75%和15.07%;其中7种人体必需氨基酸含量分别为6.18%和5.91%,占总氨基酸含量的39.24%和39.22%,必需氨基酸中均是赖氨酸含量最高,蛋氨酸含量最低,必需氨基酸指数分别为84.99和83.84;根据氨基酸评分(AAS),红和黑第一限制性氨基酸均为缬氨酸;根据化学评分(CS),红和黑第一限制性氨基酸均为蛋氨酸+胱氨酸;红和黑肌肉必需氨基酸构成比例均符合FAO/WHO的标准。红∑MUFA、∑PUFA、EPA+DHA含量以及n-6/n-3PUFA均高于黑。结果表明,红和黑都具有较高的营养价值,红的营养价值略高于黑。     

深水网箱和池塘养殖凡纳滨对虾肌肉营养成分的比较分析

对深水网箱和池塘养殖凡纳滨对虾(Litopenaeus vannamei)肌肉常规营养成分、氨基酸和脂肪酸质量分数进行了比较分析。结果显示:1)网箱养殖对虾肌肉粗蛋白质量分数显著高于池塘养殖(P0.05),而水分、粗脂肪和粗灰分质量分数无显著差异(P0.05);2)肌肉中检测到18种常见氨基酸,网箱养殖对虾肌肉氨基酸总量(TAA)、天门冬氨酸(Asp)、异亮氨酸(Ile)、精氨酸(Arg)和脯氨酸(Pro)质量分数显著高于池塘养殖(P0.05),而必需氨基酸(EAA)、半必需氨基酸(HEAA)、鲜味氨基酸(DAA)和虾味氨基酸(PFAA)两者无显著差异(P0.05);3)肌肉中检测到30种常见脂肪酸,两者的饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)、多不饱和脂肪酸(PUFA)、n-3多不饱和脂肪酸(EPA和DHA)质量分数差异显著(P0.05),以网箱养殖对虾较高;两者的棕榈酸(C16∶0)质量分数最高,且网箱养殖对虾EPA+DHA质量分数是池塘养殖的1.90倍。结果表明,网箱养殖对虾营养成分要优于池塘养殖,具有较高的营养价值。     

雌雄条纹锯(鱼旨)肌肉营养成分的比较与评价

本研究对雌雄条纹锯鮨(Centropristis striata)肌肉的营养成分进行了比较分析,并对其品质进行了评价与对比。结果显示,雌性条纹锯鮨肌肉中的水分极显著低于雄性(P<0.01),粗脂肪极显著高于雄性(P<0.01),粗蛋白质和灰分含量无显著差异(P>0.05)。雌雄条纹锯鮨肌肉中均检测出16种氨基酸,除蛋氨酸、赖氨酸和甘氨酸的含量具有显著性差异(P<0.05)外,其他13种氨基酸以及氨基酸总量(TAA)、必需氨基酸总量(EAA)和鲜味氨基酸含量(DAA)都不存在显著性差异(P>0.05)。依据氨基酸评分标准(AAS)和化学评分标准(CS)分值,雌雄条纹锯鮨肌肉的第一限制性氨基酸均为蛋氨酸,第二限制性氨基酸均为缬氨酸。雄性条纹锯鮨肌肉的必需氨基酸指数高于雌性,雌性为84.83,雄性为85.28。其必需氨基酸的组成比例均符合FAO/WHO标准。雄性条纹锯鮨肌肉的支链氨基酸和芳香族氨基酸的比值(F值)略高于雌性,雄鱼为2.28,雌鱼为2.24。雄性条纹锯鮨的单不饱和脂肪酸(MUFA)极显著高于雌性(P<0.01),多不饱和脂肪酸(PUFA)和EPA+DHA的含量差异均不显著(P>0.05)。雄性肌肉的∑n-3PUFA/∑n-6PUFA高于雌性,雄性为6.43,雌性为5.51。另外,雄性肌肉的钾钠比(K/Na)也高于雌性,雌鱼为8.27,雄鱼为14.27。研究表明,雄性条纹锯鮨比雌性具有更高的食用价值。     

红(鮰)和黑(鮰)肌肉营养成分的比较分析

本研究利用常规生化和物理分析方法对红色斑点叉尾(鮰)(Red Ictalurus punctatus)(简称红(鮰))和黑色斑点叉尾(鮰)(Black Ictalurus punctatus)(简称黑(鮰))背部肌肉一般营养成分、质构特性、氨基酸和脂肪酸含量进行了分析,并对其营养价值进行了评价.结果显示:黑(鮰)水分显著高于红(鮰),粗脂肪含量显著低于红(鮰).红(鮰)肌肉咀嚼性显著高于黑(鮰).红(鮰)和黑(鮰)的氨基酸组成基本一致,均含有18种氨基酸(除色氨酸),总含量占鲜肉的15.75％和15.07％;其中7种人体必需氨基酸含量分别为6.18％和5.91％,占总氨基酸含量的39.24％和39.22％,必需氨基酸中均是赖氨酸含量最高,蛋氨酸含量最低,必需氨基酸指数分别为84.99和83.84;根据氨基酸评分(AAS),红(鮰)和黑(鮰)第一限制性氨基酸均为缬氨酸;根据化学评分(CS),红(鮰)和黑(鮰)第一限制性氨基酸均为蛋氨酸+胱氨酸;红(鮰)和黑(鮰)肌肉必需氨基酸构成比例均符合FAO/WHO的标准.红(鮰)∑MUFA、∑PUFA、EPA+DHA含量以及n-6/n-3 PUFA均高于黑(鮰).结果表明,红(鮰)和黑(鮰)都具有较高的营养价值,红(鮰)的营养价值略高于黑(鮰).     

中华绒螯蟹池塘套养与温室养殖的中华鳖雄体生物学指数和营养成分比较

分别取中华绒螯蟹(Eriocheir sinensis)池塘套养和温室养殖中华鳖(Trionyx sinensis)雄体(分别简称为"套养鳖"和"温室鳖")各5只,解剖取四肢肌肉、裙边和肝脏,分析和比较两种鳖的生物学指数,可食组织常规营养成分、氨基酸含量和脂肪酸组成的差异。结果显示:(1)温室鳖裙边指数(SI)和肝体比(HSI)均显著高于套养鳖(P0.05)。(2)套养鳖肌肉灰分和裙边水分含量均显著高于温室鳖,而裙边蛋白含量则以温室鳖较高(P0.01),套养鳖和温室鳖其余常规营养成分均无显著差异(P0.05)。(3)温室鳖肌肉和裙边中的大部分氨基酸、总必需氨基酸(∑EAA)和总氨基酸(TAA)含量显著高于套养鳖,半胱氨酸含量及EAA/TAA以套养鳖较高(P0.05);套养鳖和温室鳖肌肉和裙边中的必需氨基酸评分(EAAS)较为接近,而EAAS平均值以套养鳖较高。(4)温室鳖肌肉C18:1n9、C18:1n7及单不饱和脂肪酸(∑MUFA)总量显著高于套养鳖,而C22:6n3、总多不饱和脂肪酸(∑PUFA)、∑n-3PUFA、总高度不饱和脂肪酸(∑HUFA)含量及n-3/n-6以套养鳖较高(P0.05);就裙边而言,除温室鳖C17:0和C20:2n6含量显著高于套养鳖外(P0.05),其余脂肪酸含量均无显著差异(P0.05)。综上可见,中华鳖在两种养殖模式下均具有较高的营养价值。     

池塘内循环流水养殖斑点叉尾鮰肌肉品质的分析

为探讨池塘内循环流水养殖(IPA)与常规池塘养殖(TPA)的斑点叉尾鮰(Ictalurus punctatus)肌肉品质差异, 测定两种养殖模式下斑点叉尾鮰 3 个不同部位肌肉(背部、腹部和尾部)的营养成分, 同时分析斑点叉尾鮰背部肌肉的质构和肌纤维特性。结果显示: IPA 组尾部肌肉粗蛋白含量显著高于 TPA 组(P<0.05), IPA 组背部和尾部肌肉粗脂肪含量显著低于 TPA 组(P<0.05)。背部肌肉中氨基酸总量、必需氨基酸总量和鲜味氨基酸总量 IPA 组显著高于 TPA 组(P<0.05); 腹部肌肉中的必需氨基酸总量和鲜味氨基酸总量 IPA 组显著高于 TPA 组(P<0.05)。17 种检出脂肪酸中, IPA 组背部、腹部和尾部肌肉中豆蔻酸的含量显著低于 TPA 组(P<0.05), 而二十碳五烯酸(EPA)的含量显著高于 TPA 组(P<0.05); 在背部和腹部肌肉中 PUFA 的总量存在显著差异, 均为 IPA 组高于 TPA 组(P<0.05)。肌肉质构特性方面, IPA 组斑点叉尾鮰肌肉的硬度、弹性、咀嚼性和回复性显著高于 TPA 组(P<0.05); IPA 组斑点叉尾鮰肌纤维直径小、密度高。结果表明, 池塘内循环流水养殖斑点叉尾鮰肌肉品质与营养更具优势。     

短期饥饿对大鳍鱯生化组成、氨基酸和脂肪酸组成的影响

在水温(21±1)℃条件下,研究了大鳍鱯(Mystus macropterus)在短期饥饿胁迫下生化组成、氨基酸和脂肪酸含量的变化.实验时间分别为饥饿0 d(S0)、饥饿3 d(S3)、饥饿6 d(S6)、饥饿9 d(S9)和饥饿12 d(S12).随着饥饿时间延长,水分显著升高(P<0.05),蛋白质、肝糖原和肌糖原显著降低(P<0.05),脂肪和灰分先显著降低(P<0.05),饥饿9 d均出现回升(P<0.05).氨基酸总量、必需氨基酸和非必需氨基酸含量均呈规则波动,饥饿12 d均出现反弹现象,略高于实验起始值.饱和脂肪酸(SFA)呈先下降、后上升、再下降的趋势,单不饱和脂肪酸(MUFA)先上升后呈规则波动,多不饱和脂肪酸(PUFA)变化规律与饱和脂肪酸恰好相反,饥饿12 d时仅高不饱和脂肪酸被保留,略高于实验起始值.双键位置不同的脂肪酸在饥饿过程中的损失速度也有差异,具体为∑n-9PUFA＞∑n-3PUFA＞∑n-6PUFA.     

Effect of dietary lipid level on growth performance and feed utilization of juvenile kelp grouper Epinephelus bruneus

A growth trial was conducted to evaluate the effect of dietary lipid level on juvenile kelp grouper Epinephelus bruneus. Juvenile kelp grouper were fed isonitrogenous diets (470 g/kg crude protein) with four levels of crude lipid at 60 g/kg (CL60), 130 g/kg (CL130), 210 g/kg (CL210), and 270 g/kg (CL270) for 56 days. The highest growth performance and feed utilization were found in the CL130 diet group. A high dietary lipid level (CL270 diet) significantly decreased growth performance and feed utilization. A significant difference in apparent digestibility was only observed in protein, which was highest in the CL130 diet groups. The highest retention for protein, energy, and lipid was found in the CL130 diet group. The dietary lipid levels significantly changed whole-body and liver compositions, the highest being the CL60 diet group for crude protein level and the CL210 diet group for crude lipid level. Based on a second-order polynomial regression analysis of crude lipid level against specific growth rate and protein efficiency ratio, the optimum dietary lipid level for kelp grouper was estimated to be 152 and 154 g/kg diet, respectively.     

Growth performance and metabolic utilization of diets with native and waxy maize starch by gilthead sea bream (Sparus aurata) juveniles

The effect of dietary starch source and level on growth performance, feed utilization, apparent digestibility coefficients and liver enzyme activities involved in intermediary metabolism of gilthead sea bream juveniles was studied. Five isonitrogenous (47% crude protein) and isolipidic (15% crude lipids) diets were formulated to contain 10% native (diet NS10) or waxy (diet WS10) maize starch; 20% native (diet NS20) or waxy (diet WS20) maize starch or no starch (control). Diets were adjusted with α-cellulose. Another diet was formulated without carbohydrates, and contained 70% crude protein and 15% crude lipids (diet HP). Each diet was fed to triplicate groups of 30 fish (initial weight: 20 g) for 12 weeks. The HP group was fed to near satiation and the other 5 groups were fed on a pair-feeding scheme according to the group that ingested less feed (control diet group). The reduction of dietary protein level from 70% to 47% by the incorporation of 20% starch did not significantly affect gilthead sea bream growth performance or feed efficiency. Compared to the control diet, neither the level nor the nature of starch had any measurable effect on growth performance and feed efficiency. Digestibility of starch was unaffected by source or dietary inclusion level. Diet had no effect on plasma glucose levels, but liver glycogen was higher in diet groups NS20, WS20 and HP. Dietary carbohydrates increased GK and G6PD enzyme activities and decreased ALAT and GDH enzyme activities while had only a minor effect on FBPase activity. The nature of dietary starch tested (native or waxy) had little influence on performance criteria.     

The influence of a dietary lipid source on growth, muscle fatty acid composition and erythrocyte osmotic fragility of hybrid tilapia

An 8-week feeding trial was conducted to determine the effects of various dietary lipids on the growth, tissue proximate composition, muscle fatty acid composition and erythrocyte osmotic fragility of red hybrid tilapia, Oreochromis sp. Five isonitrogenous and isoenergetic semipurified diets were supplemented with 10% of either cod liver oil (CLO), sunflower oil (SFO), crude palm oil (CPO), crude palm kernel oil (CPKO), or a combination of 5% CLO with 5% palm fatty acid distillates (PFAD), respectively. There were no significant effects (P > 0.05) of diet on growth but fish fed the CLO diet showed a significantly (P< 0.05) poorer feed efficiency ratio compared to fish fed the CPO diet. Lipid deposition in fish muscle was mostly similar among fish fed the various diets but bone ash was significantly higher in fish fed the CPO and CPKO diets. Muscle lipids of fish fed palm oil-based diets did not increase in saturated fatty acids content but showed significantly lower polyunsaturated fatty acid (PUFA) concentrations compared to fish fed the CLO diet. The concentrations of individual PUFA in muscle lipids were strongly influenced by dietary PUFA concentrations. Dietary lipids did not markedly affect the structural integrity of erythrocyte membranes but the erythrocytes of tilapia fed the CPO diet were slightly more resistant to osmotic lysis. It was concluded that palm oil products, especially CPO, could be successfully used in the diet of hybrid tilapia based on its availability, cheaper costs and its potential ability to enhance oxidative stability due to its low PUFA content and high natural concentrations of antioxidants.     

Effect of nucleotides supplementation to low‐fish meal feed on long‐chain polyunsaturated fatty acid composition of juvenile rainbow trout Oncorhynchus mykiss

A feeding trial was conducted to evaluate the effect of nucleotides supplementation to low‐fish meal feed on growth and fatty acid composition of rainbow trout. Six isonitrogenous (42% crude protein) and isolipidic (18% crude lipid) diets were formulated containing fish meal and plant ingredients as main protein sources. The control diet was a basal diet without supplementation of nucleotides, and five experimental diets were prepared by supplementing one of the five different nucleotides in the form of 5′‐monophosphate (0.15%), that is inosine (IMP), adenosine (AMP), guanosine (GMP), uridine (UMP) and cytidine (CMP) onto basal diet. Two hundred forty juvenile rainbow trout with an initial average body weight 9.8 g were randomly distributed into twelve aquaria. After 15 weeks of feeding period, growth performance and feed utilization of rainbow trout were not significantly different among dietary treatments. Dietary GMP, UMP and CMP tended to accumulate crude lipid in the muscle and whole fish body. Moreover, dietary GMP, UMP and CMP significantly increased hepatic 18:3n‐3 and long‐chain homologue 18:4n‐3 and 20:4n‐3 contents. Hepatic 18:2n‐6 content showed also increase in fish fed GMP, UMP and CMP diets, but decreased in long‐chain homologue 20:3n‐6 and 20:4n‐6 contents. Decrease in 20:4n‐6, 20:5n‐3 and 22:6n‐3 contents was also found in the muscle of fish fed IMP, GMP and CMP diets. The present study clearly showed that there was no positive effect of dietary nucleotides on growth of fish, but dietary nucleotides particularly GMP, UMP and CMP altered polyunsaturated fatty acid composition of rainbow trout.     

Effects of olive pomace on growth performance,digestibility, body composition and fatty acid profile in yearling Siberian sturgeon,Acipenser baerii (Brandt 1896)

Replacement of olive pomace (OP) with wheat flour in diet was studied in diet of yearling Siberian sturgeon (Acipenser baerii). Fish (165 ± 6.8 g) were randomly allocated to 15 fibreglass tanks (15 fish/tank, in triplicate). Fish were assigned to one of five dietary treatments at 19.1 ± 1.5°C for 8 weeks: control diet (crude protein and crude lipid at 514.6 and 188 g/kg_, respectively) and four experimental diets with 20, 50, 75 and 100 g/kg OP to replace wheat flour in the experimental diets. No significant difference was observed in the final weight, feed conversion ratio, specific growth rate, hepatosomatic index, viscera‐somatic index and survival rate among the treatments (p > 0.05). No change was seen in digestibility of protein and lipid in diets containing 20 g/kg and 50 g/kg OP compared to control group, while these values decreased with increasing in OP above 50 g/kg. Digestibility of dry matter and gross energy among the treatments demonstrated no significant difference (p > 0.05). Polyunsaturated fatty acids, especially C22:6n3 (DHA), in the muscle of the fish fed 75 g/kg and 100 g/kg OP in diets were significantly higher than control group (p < 0.05). These data show that OP could be recommended as a substitute for wheat flour in diet of S. sturgeon but its utilization for other species warranted future works.     

高脂或低蛋白日粮中添加发酵桑叶对大口黑鲈生长、代谢与抗氧化能力的影响

为研究发酵桑叶对大口黑鲈(Micropterus salmoides)生长、代谢与抗氧化能力的影响,选用初始体重为11 g的大口黑鲈,随机分成3组,每组4个重复。分别饲喂基础饲料、含10%桑叶高脂饲料和含10%桑叶低蛋白饲料8周。试验结果表明:同基础饲料相比,饲料中添加发酵桑叶显著抑制低蛋白组大口黑鲈的生长,而不影响高脂组大口黑鲈的生长性能。基础饲料组大口黑鲈血清中谷丙转氨酶(ALT)活性以及甘油三酯(TG)、胆固醇(CHO)和低密度脂蛋白胆固醇(LDL-C)含量显著高于低蛋白组,与高脂组无显著差异,同时,低蛋白组血清中HDL-C/CHO和HDL-C/LDL-C比值显著高于基础饲料组和高脂组。试验组大口黑鲈血糖含量显著低于基础饲料组(P0.05)。饲料中添加发酵桑叶显著提高大口黑鲈血清中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性以及CAT/SOD比值。各组鱼体的水分、粗蛋白、粗脂肪和粗灰分含量无显著差异。由此可见,饲料中添加发酵桑叶会降低大口黑鲈血脂、血糖,增强其机体的抗氧化作用。     

胆汁酸对草鱼(Ctenopharyngodon idellus)的生长性能、肌肉营养成分及消化酶活性的影响

为研究胆汁酸对草鱼(Ctenopharyngodon idellus)生长性能、肌肉营养成分及消化酶活性的影响,选取初始体重为(13.11±0.58)g的草鱼540尾,随机分成6个实验组,分别饲喂胆汁酸添加量为0、75、150、225、300、375 mg/kg的等氮等能饲料(粗蛋白含量34.56％,总能13.54 kJ/g),养殖时间为60 d.结果显示,随着胆汁酸浓度的增加,草鱼的增重率(WGR)、特定生长率(SGR)均呈先上升后下降的变化趋势,且均在胆汁酸添加量为300 mg/kg时达到最大值(分别为281.18％和2.23％/d);饲料系数(FCR)则呈先下降后上升的趋势,且在胆汁酸添加水平为225 mg/kg时达最低值(1.26).由二次回归方程可知,WGR、SGR、FCR等生产性能最优时,胆汁酸添加水平分别为222.15、265.00、242.86 mg/kg.实验鱼肌肉粗脂肪含量随胆汁酸添加量的增加而呈先下降后趋于稳定的变化趋势,粗蛋白质含量则呈先上升后降低的变化趋势.肠道各段及肝胰脏的消化酶活性均随胆汁酸添加量的增加呈先升高后下降的趋势.由此说明,适量的胆汁酸能提高草鱼生长性能,促进其脂肪代谢,降低机体脂肪沉积,改善其肌肉品质.本研究考虑到草鱼消化酶活性、肌肉品质及生长性能等因素,其饲料中胆汁酸适宜的添加量为222.15-265.00 mg/kg.     

不同饵料比对黄鳝生长及生理生化指标的影响

以冰鲜鱼与配合饲料5个不同比例饵料饲养黄鳝(Monopterus albus)14周,设定配合饲料所占比例分别为0％、25％、50％、75％、90％,研究不同饵料比处理对黄鳝生长、体成分及部分血清生理生化指标的影响.结果显示,各处理组黄鳝增重率、成活率均无显著差异(P＞0.05);粗蛋白及粗脂肪含量随饵料中配合饲料比例增大呈先升高、后降低的趋势,且均以90％配合饲料组最低;而各组体灰分和水分差异不显著(P＞0.05);各处理组黄鳝的血清谷草转氨酶(GOT)、谷丙转氨酶(GPT)、甘油三酯、总胆固醇及血糖有显著差异(P＜0.05);与完全投喂冰鲜鱼(0％组)相比,其它各处理组血清GOT和GPT显著降低;75％配合饲料组血清GOT、GPT(50％组除外)、总胆固醇均为所有处理组最低;表明黄鳝投喂以25％冰鲜鱼和75％配合饲料的混合饵料为宜.     

Effect of Dietary Charcoal and Wood Vinegar Mixture (CV82) on Body Composition of Olive Flounder Paralichthys alivaceus

The effects of dietary charcoal and wood vinegar mixture (CV82) were determined on growth, body composition, and vitality of olive flounder Paralichrhys alivaceus . Five experimental diets were formulated to contain 0% (control), 0.5%, 1.0%, 1.5%, and 2.0% CV82. Weight gain was lowest in the control diet group (47.7 g) and highest in the 1.0% CV82 group (53.0 g). Feed efficiency was lowest in the control diet group (87.3%) but significantly higher in the 0.5% CV82 diet group (95.8%), ( P > 0.05). The condition factor and hepatosomatic index were not affected by the dietary level of CV82. Moisture and crude protein content did not significantly differ among the treatments. However, crude lipid was lower in the 1.0% and 1.5% CV82 diet groups of 3.4% and 3.5%, respectively. Serum glutamic oxaloacetic acid and glutamic pyruvic transaminase activities decreased significantly with increasing dietary CV82 level. Therefore, these results suggested that the suitable dietary CV82 level could be between 0.5% and 1.0% in olive flounder for the maximum weight gain, feed efficiency, and vitality.