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1.
以凡纳滨对虾(Litopnnaus vannamei)幼虾为实验动物,在其基础饲料中分别添加芽孢杆菌(Bacillus sp.)胞外蛋白粗提物(1.0%,胞外蛋白组)、胞内多糖粗提物(1.0%,胞内多糖组),以基础饲料为对照组饲料,进行为期28d的养殖实验,探讨芽孢杆菌胞外蛋白和胞内多糖粗提物对幼虾生长、能量代谢及抗病能力的影响。研究表明,芽孢杆菌2种粗提物对凡纳滨对虾的生长和成活率影响不显著(P>0.05)。饲喂2种粗提物影响了凡纳滨对虾肝胰腺和肌肉中能量代谢相关酶活力。胞外蛋白组肝胰腺中磷酸果糖激酶(PFK)、乳酸脱氢酶(LDH)活力在养殖实验前期显著高于对照组(P<0.05),而肌肉中PFK、LDH活力显著低于对照组(P<0.05);胞内多糖组肝胰腺中己糖激酶(HK)活力及肌肉中PFK、LDH活力显著低于对照组(P<0.05)。饲喂2种粗提物均显著提高了凡纳滨对虾肌肉中琥珀酸脱氢酶(SDH)活力和肝胰腺中电子传递系统(ETS)活力(P<0.05),胞外蛋白粗提物对肝胰腺中的SDH活力也有显著的提高作用(P<0.05)。饲喂2种粗提物显著降低了凡纳滨对虾肝胰腺及肌肉组织中脂肪酸合酶(FAS)含量(P<0.05)。此外,饲喂2种粗提物均会显著提高凡纳滨对虾肠道蛋白酶活力(P<0.05),而胞外蛋白粗提物使凡纳滨对虾肠道脂肪酶活力显著降低(P<0.05)。白斑综合征病毒(WSSV)感染后,与对照组相比,胞外蛋白组和胞内多糖组凡纳滨对虾半致死时间分别延长了26.19%和7.14%。根据以上结果推测,芽苞杆菌2种粗提物能够影响凡纳滨对虾能量代谢水平并提高其抗WSSV能力,且二者之间密切相关。  相似文献   

2.
本文探讨了三种植物油全部替代饲料中鱼油对虹鳟生长性能与各组分能量收支分配的影响。实验设置以鱼油为对照组,三个实验组脂肪源分别为大豆油、棕榈油、菜籽油,各组脂肪水平为20%。在16℃下饲养52d,每天饱食投喂两次。实验结果表明:(1)三种植物油替代鱼油对虹鳟生长性能无显著差异,但饲料中添加不同脂肪源对虹鳟各组分能量值以及能量分配影响显著;(2)添加大豆油组消化率93.19%,高于鱼油组92.07%、菜籽油组92.08%与棕榈油组92.03%,同时大豆油组粪便能分配率最低5.01%,但代谢能分配率最高41.04%(P0.01);(3)菜籽油组排泄能分配最低为29.09%,表现出最佳能量分配策略。实验结果表明,虹鳟饲料中脂肪以添加菜籽油的能量分配策略最佳,棕榈油和鱼油效果相似。  相似文献   

3.
养殖水环境中的离子浓度会因气候和季节的变化发生波动,对凡纳滨对虾的摄食、存活和生长产生影响。在实验室条件下,凡纳滨对虾养殖水体Ca~(2+)/Mg~(2+)保持在1∶3左右,以恒定Ca~(2+)浓度150 mg/L、Mg~(2+)浓度450 mg/L为对照组(CC0组),4 d为一个离子浓度波动周期,分别以Ca~(2+)浓度100 mg/L、Mg~(2+)浓度300 mg/L和Ca~(2+)浓度45 mg/L、Mg~(2+)浓度135 mg/L为离子浓度波动处理组(CCM1组和CCM2组),研究Ca~(2+)、Mg~(2+)浓度波动对凡纳滨对虾稚虾生长和鳃中能量代谢物质含量的影响。结果表明:在本实验条件下,Ca~(2+)、Mg~(2+)浓度波动对凡纳滨对虾稚虾的存活无显著影响。在CCM1组中,对虾的食物转化效率(FCE)、特定生长率(SGR)显著高于CC0组和CCM2组对虾(P0.05),蜕皮率也达到最高,但蜕皮率与其他两组差异不显著(P0.05)。在检测出的21种能量代谢物质中,丙酮酸等3种能量代谢物含量随水体Ca~(2+)、Mg~(2+)浓度波动幅度的升高而降低,且在CC0组对虾体内含量较高;草酰乙酸等4种能量代谢物含量随水体Ca~(2+)、Mg~(2+)浓度波动幅度的升高而降低,且在CCM1组对虾体内含量较高;NAD+等14种能量代谢物含量随水体Ca~(2+)、Mg~(2+)浓度波动幅度的升高而升高。其中,NADP+、环腺苷酸、丙酮酸和α-酮戊二酸的含量变化达到显著水平(P0.05)。研究结果表明:周期性Ca~(2+)、Mg~(2+)浓度波动条件下,凡纳滨对虾具有生长差异,且在能量平衡上产生积极响应。适宜范围内的Ca~(2+)、Mg~(2+)浓度波动,促进凡纳滨对虾的生长,这与其能量储备和平衡相关。  相似文献   

4.
为探讨斜带石斑鱼(Epinephelus coioides)在低盐水体下最适的摄食水平,在水体盐度12、温度28℃±1℃的条件下,作者投喂人工配合饲料,研究了不同摄食水平(分别为体质量的2.36%、2.83%、3.31%、3.79%、4.25%及饱食)对斜带石斑鱼幼鱼(初始体质量为29.28 g±2.63 g)生长和能量收支的影响,并建立了生长-摄食关系和不同摄食水平下的能量收支方程。结果表明,在低盐下幼鱼鱼体粗蛋白及灰分含量在各摄食水平组间无显著差异(P0.05);脂肪含量在3.79%、4.25%及饱食组显著高于其他摄食水平组(P0.05);干物质含量在4.25%、饱食组显著高于其他摄食水平组(P0.05);能量含量随摄食水平降低而下降。摄食水平对幼鱼摄食率有显著影响(P0.05)且随摄食水平的降低而下降。幼鱼湿质量特定生长率、干质量特定生长率、蛋白特定生长率、能量特定生长率均随着摄食水平的增加而增加。特定生长率与摄食水平呈减速增长曲线关系,可用对数方程描述。幼鱼饲料湿质量转化效率、饲料干质量转化效率、饲料蛋白转化效率均随摄食水平的增加先增大后减少的变化,在3.79%组达到最大值,饲料能量转化效率随摄食水平的增加呈一直增加,在饱食组达到最大值。随着摄食水平的增加,生长能(G)呈先升后降的变化,在3.79%组有最大值,与摄食水平之间可用一元二次方程表述;排粪能(F)与排泄能(U)呈一直增大的变化,在饱食组有最大值,与摄食水平之间均可用线性方程表述;代谢能(R)则呈降低并逐渐趋于平稳的变化。在3.79%组,幼鱼获得最佳的能量收支方程为:100.00C=12.29F+13.73U+31.33R+42.65G。综合考虑认为,斜带石斑鱼幼鱼在低盐水体下最适的摄食水平为体质量的3.79%。  相似文献   

5.
以0.04%的Y2O3为外源性指示剂,按照70%基础饲料:30%待测原料的比例配制成实验饲料,测定军曹鱼(Rachycentron canadum L.)对白鱼粉、虾壳粉、血粉、水解羽毛粉、酪蛋白、明胶和棉籽粕干物质、蛋白质、氨基酸和能量的表观消化率。结果表明,干物质表观消化率范围为54.1%~73.4%,鱼粉、血粉和水解羽毛粉干物质消化率最高(70.2%~73.4%),而血粉最低(P<0.05)。除血粉外各原料蛋白质表观消化率均高于85%,其中白鱼粉、虾壳粉和酪蛋白蛋白质消化率均高于90%,而血粉显著低于其它各原料(75.1%)(P<0.05)。原料氨基酸表观消化率变化趋势与蛋白质消化率相一致。能量表观消化率范围为70.6%~86.7%,白鱼粉、水解羽毛粉、酪蛋白和明胶能量消化率显著高于虾壳粉、血粉和棉籽粕,而棉籽粕能量消化率最低(P<0.05)。  相似文献   

6.
几种虾、贝、藻混养模式能量收支及转化效率的研究   总被引:1,自引:0,他引:1  
实验采用围隔实验方法,对凡纳滨对虾(Litopenaeus vannamei)、青蛤(Cyclina sinesis)、菊花心江蓠(Gracilarialichevoides)和活菌净水剂的不同单、混养生态系统的能量收支和转化效率进行了研究。实验结果表明,实验期间系统接受的总太阳光辐射能为1 983.2 MJ/m2。浮游植物对光能的利用效率在各处理间无差异(0.147±0.007)%,混养江蓠显著地提高了总利用效率(0.308±0.019)%。总能量的转化效率,虾藻混养(28.36%)和江蓠单养(27.65%)最高,其次是虾贝藻混养(26.70%),对虾单养(12.24%)最低。单位净产量对饲料能的消耗,对虾单养(21.24 MJ/kg)最多,虾菌、虾贝混养(18.76~18.97 MJ/kg)次之,而虾藻、虾贝藻混养(2.64~3.24 MJ/kg)则显著地降低了饲料消耗量。实验中投喂组都有较多的能量沉积,对虾单养沉积量达到1.10 MJ/m2,虾贝混养(1.30 MJ/m2)稍高,而虾贝藻、虾菌、虾藻混养平均为0.53 MJ/m2,显著地低于对照。结果表明,混养青蛤和菊花心江蓠显著地提高了对虾养殖中的光能利用率和能量转化效率,减少了能量沉积,从而大大地提高了能量的利用效率。  相似文献   

7.
以酪蛋白和明胶为蛋白源 ,添加豆油、鱼油、糊精、纤维素以及适量的维生素和矿物质混合剂配制试验饲料 ,饲料配成5个蛋白质水平 ,每个蛋白水平分别包括5个能量级 ,以体质量增长倍数、蛋白质效率和饲料系数为评判依据 ,对体质量为8.73g±0.79g的中华鲟(Acipensersinensis)的适宜蛋白质含量及其蛋白能量比进行了研究。经过为期8周的试验 ,结果表明 :中华鲟幼鲟配合饲料中的适宜蛋白质含量范围为35.7%~41.8% ,饲料的最佳蛋白能量比范围为21.85~30.05ng/J。当试验饲料蛋白质含量为40.3% ,蛋白能量比为27.85ng/J时 ,试验鲟鱼获得最大体质量增长倍数为11.60±1.20,最低的饲料系数为1.68±0.23,以及最高的蛋白质效率为1.58%±0.14%。  相似文献   

8.
泥蚶(Tegillarca granosa)精氨酸激酶的基因克隆与表达   总被引:1,自引:1,他引:0  
利用PCR扩增技术,从泥蚶的cDNA文库中克隆出了精氨酸激酶(arginine kinase)基因,并进行了原核表达.精氨酸激酶是调节能量代谢的重要酶类,在无脊椎动物体内能量平衡过程中起重要作用.结果表明,泥蚶的精氨酸激酶全长1601bp,包括5'非翻译区(5'-UTR)序列332bp,3'非翻译区(3'-UTR)序列...  相似文献   

9.
卵黄囊期是鱼类早期发育中的一个重要阶段,是鱼类由内源营养向外源营养转化的一个关键时期。从能量学的角度来分析,则表现为主要能源物质在发育过程中有规律的变化,各能量物质按一定顺序被利用。探讨卵黄囊期海洋硬骨鱼类的能量转化规律,定量分析发育中生化成分和能量物质的变化,预测维持仔鱼生命活动和提供生长所必需的合适饵料营养成分,可为养殖生产中提高早期育苗成活率提供理论依据。作者着重探讨褐牙鲆卵黄囊期能量代谢特点及生化物质变化规律。  相似文献   

10.
饲料中主要能量物质对大菱鲆幼鱼生长的影响   总被引:9,自引:0,他引:9  
于1999年6-8月,采用正交设计统计方法,对主要能量物质蛋白质、脂肪和糖类对大菱Ping幼鱼生长的影响进行研究。利用L16(4^3)正交设计了16组大菱Ping幼鱼饲料,在各级饲料中,蛋白质、脂肪和糖类的含量范围分别为36%-45%、8%-20%和0%-6%,共进行了60d的喂养实验,并对饲料及鱼体成分进行分析测定。结果表明,各主要能量物质对鱼体增重和配合饲料转化率的影响顺序为蛋白质>糖类>脂肪,且蛋白质的变化对增重率的影响极显著,对饲料转化率的影响显著。  相似文献   

11.
In studies with larval stages of the American lobster (Homarus americanus) exposed to a sublethal concentration of South Louisiana crude oil, the normal patterns of lipid storage, utilization and synthesis during larval development and metamorphosis were altered with oil exposure. Increased rates of protein catabolism, delayed molting and reduced growth were also evident among oil-exposed lobster larvae and suggest either deficiency or immobilization of lipid reserves. From analyses of lipid class composition of control and oil-exposed lobster larvae, it is evident that oil-exposed larvae have consistently lower levels of triacylglycerols (the major energy store) and higher levels of sterols than control larvae. Decreased ratios of non-essential fatty acids (both saturated and unsaturated) and increased ratios of essential fatty acids were detected in the neutral lipid pools of oil-exposed larvae that suggest both decreased storage of fatty acids in energy reserves and decreased mobilization of essential fatty acids into phospholipid pools. The fatty acid distribution in the phospholipid pools of oil-exposed larvae, however, varied little from control values and reflects a tendency to preserve the integrity of these structural lipids. Increases in sterol levels may be related to decreased mobilization of cholesterol or other sterols and/or transformation of cholesterol into metabolic pathways including the biosynthesis of ecdysterone.Oil-exposed animals contained trace quantities of benzene, thiophene, toluene, alkylcyclohexane and alkylbenzenes, detected with GC-MS analyses. No naphthalene, dimethylnaphthalene, higher molecular weight aromatics or their phenolic derivatives were detected; their absence may be related to either the detection limits of the methodology used or extremely rapid metabolism and turnover of these components. Alterations in lipid metabolism may account for the developmental and energetic abnormalities observed in marine crustaceans. It cannot be ruled out, however, that decreased lipid utilization, synthesis and mobilization may be a defense mechanism against incorporating lipophilic components of petroleum hydrocarbons in metabolic pathways, and that disruption in energetics and development is a consequence of the reduction in energy available for growth and molting.  相似文献   

12.
Energy contents of several freshwater animal species collected from Lake Ellesmere, Canterbury, were determined by bomb calorimetry. Values are shown to vary seasonally and between size classes. Because of this variability the use of a single energy value of an organism in an energetics study is not recommended.  相似文献   

13.
Current development plans indicate that during the next decade there will be an increase in tidal stream and wave (TSW) power generation activity in Scottish Waters, together with the designation of additional offshore areas for seabird conservation. This paper summarises how TSW developments could affect seabirds, based on experience from other forms of disturbance, and explores the possible changes in behaviour and habitat that have the potential to increase a seabird's rate of energy acquisition (e.g. through enhancing prey abundance), or energy expenditure (e.g. through causing birds to commute further to find food, if they avoid foraging around developments placed in regular feeding areas). Changes to energy budgets could impact rates of reproduction and survival. Simulation modelling of seabird energetics and behaviour is one possible tool for predicting the direction and magnitude of population impacts caused by alterations to energy budgets, but is dependant on the availability and accuracy of necessary parameters. The later sections of the paper review the information needed for such models and shows that although some data are available regarding rates of energy expenditure during specific activities, more information is needed on seabird foraging rates. The paper also highlights how the susceptibility of a species to be impacted by future TSW development is likely to be related to their method of foraging, flight behaviour and ability to buffer against environmental fluctuations.  相似文献   

14.
The variability of the geostrophic eddy kinetic energy (EKE) in the Sea of Japan derived from weekly altimetric sea level anomalies spanning from 1992 through 2009 is studied. Nonorthogonal modes of variability are revealed accounting for more than 60% of the total variance. They capture the seasonal variation of the mesoscale energetics in the entire Sea of Japan with the EKE growing in the warm season up to the maximum in October through November and diminishing in the cold season down to the minimum in March through April. In the northern Sea of Japan (northward of the Subarctic Front), where the mean EKE is several times less than in the southern sea, areas of considerable variability are detected. Quasi-biennial EKE oscillations are revealed but not the trends covering the whole record.  相似文献   

15.
用一种新的泛函工具——多尺度子空间变换(multiscale window transform, MWT),得到如实的东海涡动能分布,发现东海黑潮上下游区域的涡动能有着完全不同的季节变化特征。根据功率谱分析,东海黑潮流系可正交地重构到背景流尺度子空间(大于64 d)与涡旋尺度子空间(小于64 d),并用MWT得出相应子空间的能量,后者即为涡动能。结果表明,上游涡动能在8月达到峰值,冬季最弱;而下游涡动能在4月和9月存在两个峰值,冬季最弱。利用基于MWT的正则传输理论以及局地多尺度能量分析方法,发现正压不稳定和斜压不稳定是东海黑潮涡动能的主要来源,且这两个来源决定了其上下游不同的季节变化。其中上游涡动能的季节变化主要受正压不稳定路径(即背景流动能向涡动能的正则传输)控制,而下游涡动能在4月的峰值主要由斜压不稳定路径(即背景流有效位能向涡旋有效位能作正则传输并进一步转化为涡动能)决定,其在9月的峰值受到正压不稳定和斜压不稳定的共同影响。  相似文献   

16.
Two important nonlinear properties of seawater thermodynamics linked to changes of water density, cabbeling and elasticity(compressibility), are discussed. Eddy diffusion and advection lead to changes in density; as a result, gravitational potential energy of the system is changed. Therefore, cabbeling and elasticity play key roles in the energetics of lateral eddy diffusion and advection. Vertical eddy diffusion is one of the key elements in the mechanical energy balance of the global oceans. Vertical eddy diffusion can be conceptually separated into two steps: stirring and subscale diffusion. Vertical eddy stirring pushes cold/dense water upward and warm/light water downward; thus, gravitational potential energy is increased. During the second steps, water masses from different places mix through subscale diffusion, and water density is increased due to cabbeling. Using WOA01 climatology and assuming the vertical eddy diffusivity is equal to a constant value of 2×103 Pa2/s, the total amount of gravitational potential energy increase due to vertical stirring in the world oceans is estimated at 263 GW. Cabbeling associated with vertical subscale diffusion is a sink of gravitational potential energy, and the total value of energy lost is estimated at 73 GW. Therefore, the net source of gravitational potential energy due to vertical eddy diffusion for the world oceans is estimated at 189 GW.  相似文献   

17.
The energetics of the most destructive tsunami in historical time, and that of the under ocean earthquake that triggered this tsunami of 26 December 2004 in the Indian Ocean have been briefly reviewed. This latest tsunami has several other unique characteristics besides being one of the worst natural disasters in human history. It is the first truly global tsunami after modern seismographic and sea level monitoring networks have been put in place. It was the first tsunami on record detected by a satellite, even though at present, global satellite coverage of the oceans for real time tsunami detection is not adequate. Finally, the energy associated with the tsunami and the earthquake that triggered it is so large that speculation has been made about the normal modes of oscillation of the earth, that were triggered by the earthquake as well as some suggestions, that some of the earth's rotational characteristics may have temporarily changed to a discernible degree. Here, we briefly review the energetics of the tsunami and the earthquake that triggered it.  相似文献   

18.
An internal gravity wave model was employed to simulate the generation of internal solitary waves(ISWs) over a sill by tidal flows. A westward shoaling pycnocline parameterization scheme derived from a three-parameter model was adopted, and then 14 numerical experiments were designed to investigate the influence of the pycnocline thickness, density difference across the pycnocline, westward shoaling isopycnal slope angle and pycnocline depth on the ISWs. When the pycnocline thickness on both sides of the sill increases, the total barotropic kinetic energy, total baroclinic energy and ratio of baroclinic kinetic energy(KE) to available potential energy(APE) decrease, whilst the depth of isopycnal undergoing maximum displacement and ratio of baroclinic energy to barotropic energy increase. When the density difference on both sides of the sill decreases synchronously, the total barotropic kinetic energy, ratio of baroclinic energy to barotropic energy and total baroclinic energy decrease, whilst the depth of isopycnal undergoing maximum displacement increases. When the westward shoaling isopycnal slope angle increases, the total baroclinic energy increases whilst the depth of turning point almost remains unchanged. When the depth of westward shoaling pycnocline on both sides of the sill reduces, the ratio of baroclinic energy to barotropic energy and total baroclinic energy decrease, whilst the total barotropic kinetic energy and ratio of KE to APE increase. When one of the above four different influencing factors was increased by 10% while the other factors keep unchanged, the amplitude of the leading soliton in ISW Packet A was decreased by 2.80%, 7.47%, 3.21% and 6.42% respectively. The density difference across the pycnocline and the pycnocline depth are the two most important factors in affecting the characteristics and energetics of ISWs.  相似文献   

19.
Growth and energy budget of marine amphipod juvenile Eogammarus possjeticus at different temperatures(20°C,24°C, 26°C, 28°C, 30°C, 32°C and 34°C) were investigated in this study. The results showed that the cumulative mortality rate increased significantly with rising temperature(p0.01), and exceeded 50% after 24 h when temperature was above 30°C. With the temperature increasing from 20°C to 26°C, the ingestion rate and absorption rate increased, but decreased significantly above 28°C(p0.01), indicating a decline in feeding ability at high temperatures. The specific growth rate increased with rising temperature, but decreased significantly(p0.01) after reaching the maximum value at 24°C. Similarly, the oxygen consumption and ammonia emission rates also showed a trend of first increase and then decrease. However, the O:N ratio decreased first and then increased with rising temperature, indicating that the energy demand of E. possjeticus juvenile transferred from metabolism of carbohydrate and lipid to protein. In the energy distribution of amphipods, the proportion of each energy is different. With rising temperature, the ratio of the energy deposited for growth accounted for ingested gross energy showing a trend of decrease, while the energy lost to respiration, ammonia excretion, and feces accounted for ingested gross energy being showed a trend of increase. It seemed that rising temperature increased the metabolism and energy consumption of the amphipods and, meanwhile, decreased the energy used for growth, which may be an important reason for the slow growth and small body size of the amphipods during the summer high-temperature period.  相似文献   

20.
企鹅珍珠贝耗氧率和排氨率的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
采用室内实验生态学方法对企鹅珍珠贝的耗氧率和排氨率进行了研究。旨在为企鹅珍珠贝养殖容量(carrying capacity for aquaculture)的调查及育珠生理的研究提供参考,并可为海洋生态系统动力学和贝类能量学研究提供科学依据。研究结果表明,在实验温度(13~33℃)范围内,企鹅珍珠贝的耗氧率(OR)和排氨率(NR)与体重(W)都呈负相关,可分别表示为Y1=a1W-b1和Y2=a2W-b2,其中,a1的取值范围是1.330~4.128,b1的取值范围是0.453~0.651,a2的取值范围是0.150~0.354,b2的取值范围是0.446~0.634。在实验室温度(13~33℃)条件下,企鹅珍珠贝的耗氧率为0.329~7.303 mg/(g·h),排氨率为0.035~0.489 mg/(g·h),其中耗氧率在28℃时达到最高值,33℃时开始下降,而排氨率则呈持续升高趋势。企鹅珍珠贝呼吸和排泄Q10值范围分别为0.210~2.494和1.193~2.483。在23~28℃温度范围内,不同规格企鹅珍珠贝的耗氧率和排氨率的比值(原子数O/N)较高。方差分析表明,体重、温度及二者的交互作用对企鹅珍珠贝的耗氧率和排氨率均有极显著的影响(P<0.01)。企鹅珍珠贝的日常代谢明显高于标准代谢,耗氧率和排氨率平均值分别提高32.1%和76.7%。  相似文献   

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