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1.
角褐指藻是一种单细胞蛋白,通过测定三角褐指藻藻液中的主要营养指标蛋白质的变化,旨存探讨三角褐指藻藻液的采收,研究三角褐指藻作为蛋白质饲料添加到饲料中的可能性,为饲料蛋门质提供新的来源。 相似文献
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海洋大型绿藻条浒苔与微藻三角褐指藻相生相克作用的研究 总被引：15，自引：0，他引：15
以种群密度为变量,采用实验生态学手段研究了大型海藻条浒苔与赤潮藻类三角褐指藻间的生长竞争关系,以及条浒苔水溶性抽提液对三角褐指藻生长的影响。结果表明,在无营养盐限制条件下,低密度条浒苔(0.3~0.7 g/L)均能抑制三角褐指藻(起始浓度104cell/ml)的生长,最大抑制率为74.5%;低起始浓度(102~103cell/ml)的三角褐指藻,对条浒苔具有促生长效应,而高起始浓度(104~105cell/ml)的三角褐指藻在一定程度上抑制条浒苔的生长。条浒苔水溶性抽提液(0.3~0.7 g/L)对三角褐指藻的生长皆表现出明显的抑制效应,平均抑制率为75.2%,抑制效果较条浒苔鲜组织更为明显;其最大抑制效应(84.8%)表现在接种后的第8天,三角褐指藻的生长抑制量随条浒苔水溶性抽提液浓度的增加而增大。表明条浒苔可能通过相生相克作用影响共培养体系中三角褐指藻的生长。 相似文献
3.
两种藻类饲喂中华哲水蚤的繁殖差异 总被引：1，自引：0，他引：1
通过室内实验研究了中华哲水蚤摄食三角褐指藻(Phaeodactylumtricornutum)和球等鞭金藻(Isochrysis galbana)后产卵率、孵化率变化。22d的实验时间,摄食三角褐指藻的中华哲水蚤平均产卵率为0.24±(0.07)/d,雌体存活率较低,摄食球等鞭金藻的产卵率为7.84±(1.12)/d,雌体存活亦较高。不论在藻类溶出液和过滤海水中摄食三角褐指藻后所产的卵孵化率都低于摄食球等鞭金藻者。这表明对照球等鞭金藻相比,硅藻三角褐指藻对中华哲水蚤产卵和孵化都存在明显的抑制作用。脂肪酸分析结果显示,在三角褐指藻细胞内,对桡足类繁殖十分重要的多不饱和脂肪酸(PU-FAs)和特定脂肪酸(ω3,ω6)的含量皆较低。 相似文献
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设置氮质量浓度和硅质量浓度双因子试验,探讨其对三角褐指藻生长的影响及对藻细胞增殖的交互作用,结果发现,氮质量浓度对三角褐指藻生长有极显著的影响.不论是在低硅质量浓度,还是高硅质量浓度下,与高氮处理相比较,缺氰处理下藻细胞不能存活,低氮处理下藻细胞生长受严重抑制.试验结束时,低硅质量浓度下缺氮、低氮和高氮处理的藻细胞密度分别为0、5.0×105个/mL和7.37×106个/mL.硅质量浓度同样对三角褐指藻的细胞密度产生显著性影响,高硅质量浓度下的藻细胞密度显著高于低硅质量浓度下的藻细胞密度.双因素方差分析结果表明,试验前期,氮和硅对三角褐指藻细胞密度的交互作用不明显(P＞0.05);但试验后期,氮和硅对三角褐指藻细胞密度有显著性的交互作用(P＜0.05). 相似文献
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微藻生物柴油是新能源开发的热点之一.为了提高微藻作为生物柴油原料的性能,研究了接种密度对两种产油微藻(微绿球藻Nannochloropsis oculata和三角褐指藻Phaeodactylum tricornutum)生长性能及细胞油脂特性的影响.结果表明,两种微藻细胞采收密度或采收生物量与接种密度正相关,而细胞增殖效率与接种密度负相关(P＜0.05).微绿球藻和三角褐指藻细胞油脂含量随接神密度升高而降低,微绿球藻和三角褐指藻分别在接种密度为6.0×106 cell/mL和3.0×106 cell/mL时,其细胞内中性脂比例最高.微绿球藻、三角褐指藻的饱和脂肪酸(SFA)和单不饱和脂肪酸(MUFA)比例随着接种密度的提高先升高后显著下降(P＜0.05).从生产生物柴油的效率及其品质等因素综合考虑,室验条件下,培养微绿球藻适宜接种密度为6.0×106 cell/mL;三角褐指藻适宜接神密度为2.0×106 cell/mL. 相似文献
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实验对指数生长期、指数生长末期、静止期和衰亡期的三角褐指藻脂肪酸进行研究,发现在指数生长末期二十碳五烯酸(Eicosapentaenoic acid,EPA)含量最高。实时定量PCR分析三角褐指藻Δ5脂肪酸去饱和酶基因在不同生长时期的表达变化水平差异显著,其中指数生长期表达量最高。为了探讨温度对微藻生长和脂肪酸组成的影响,作者在不同温度下对三角褐指藻进行了培养,并测定其生长和脂肪酸组成。结果表明,三角褐指藻的生长随着温度的升高到达指数生长末期所需时间缩短;不同温度下三角褐指藻的主要脂肪酸为C14∶0、C16∶0、C16∶lΔ9、Cl8∶lΔ9、C18∶2Δ9,12、C20∶5n3(EPA),总脂肪酸随着温度的升高依次呈现先升高后降低的趋势,在15℃时EPA占总脂肪酸的百分含量达到最高值25.71%。 相似文献
10.
UV-B辐射对三角褐指藻的膜酯脱酯化伤害 总被引：3，自引：0，他引：3
UV－B辐射对三角褐指藻的生长有明显的抑制效应，其96h半抑制剂量（96h EC50）为1.91J/m^2。进一步的结果表明，UV－B辐射增强能够引起藻细胞活性氧含量的增加，从而导致三角褐指藻的膜酯脱酯化伤害。 相似文献
11.
饲料蛋白质水平对拉萨裸裂尻鱼幼鱼肌肉氨基酸及蛋白质代谢的影响 总被引：2，自引：2，他引：0
本实验旨在探索饲料蛋白质水平对拉萨裸裂尻鱼(Schizopygopsis younghusbandi Regan)幼鱼肌肉氨基酸及蛋白质代谢的影响。选用初始体重为(22.42±0.56) g 的拉萨裸裂尻鱼 540 尾,随机分成 6 组,每组 3 个重复,每个重复30 尾鱼,分别投喂蛋白质水平为 20%、25%、30%、35%、40%、45%的实验饲料,养殖时间为 60 d。结果表明:随着饲料蛋白水平的增加,拉萨裸裂尻鱼氮摄入量(NI)和绝对氮摄入量(ANI)均呈逐渐升高的变化趋势。氮沉积(ND)、蛋白质效率(PER)、净蛋白质利用率(NPU)均呈先升高后降低的变化趋势。肌肉总必需氨基酸(TEAA)、总呈味氨基酸(TFAA)、总非必须氨基酸(TNEAA)、总氨基酸(TAA)随饲料蛋白的升高呈先升高后趋于稳定的变化趋势。饲料蛋白水平超过 30%后,血氨(ammonia)、尿素氮(urea)、白蛋白(ALB)显著升高。总蛋白(TP)在饲料蛋白低于 35%时呈逐渐升高的变化趋势。拉萨裸裂尻鱼肝脏谷丙转氨酶 ALT、谷草转氨酶 AST 均呈先升高后趋于稳定的变化趋势,血清 ALT呈先降低后升高的变化趋势,血清 AST在饲料蛋白含量高于 35%后显著升高。综合考虑饲料蛋白利用率、血液总蛋白含量、肝脏及血清转氨酶活性,建议拉萨裸裂尻鱼饲料蛋白含量为 30%~35%。 相似文献
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Fishmeal replacement by mixed plant proteins and effect on growth and sensory attributes in on‐growing turbot 
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下载免费PDF全文 A.K.D. Imsland T. Helmig S. Gunnarsson G.Ö. Kristjánsson 《Aquaculture Nutrition》2018,24(3):1041-1047
Fishmeal replacement with a mixture of plant protein (PP) raw materials (soya, wheat gluten meal, corn gluten meal and rapeseed meal) in diets for 300‐950 g turbot was tested. Eight different diets with fishmeal protein stepwise varying from 53.7% of crude protein (CP) to 93% of CP of the total protein in the diet were tested. The fish was weighed at monthly intervals for following of weight development and calculation of specific growth rates, daily feed intake and feed conversion ratio. At the end of the experiment, fish was sampled for sensory evaluation. Average final weight was 950 g and did not vary between the experimental groups. There were no effects of dietary treatment on specific growth rates, daily feed intake, feed conversion ratio or sensory attributes measured. The least‐cost diet (with 53.7% fishmeal protein) is about 12% lower in raw material cost (based on material price of diet components) than the all fishmeal diet. The results therefore indicate that the raw material cost in feed for on‐growing turbot can be reduced considerably without any negative effect on growth and feed utilization. 相似文献
13.
Hanne Dvergedal Jrgen
degrd Liv Torunn Mydland Margareth
verland Jon
vrum Hansen Ragnhild Martinsen nestad Gunnar Klemetsdal 《Aquaculture Research》2019,50(4):1153-1161
In growing animals, individual variation in feed efficiency may arise from individual differences in growth rate and protein metabolism. Over a period of time, these factors will affect the ratio between ‘new’ vs. ‘old’ protein, which can be quantified using isotope profiling. The aim of this study was to investigate the relationship between relative weight gain and atom percentage excess 15N in the muscle, liver and mid‐intestine. A 50‐day experiment was conducted with a total of 375 fish initially fed a standard diet, subsequently replaced by one out of five experimental diets, enriched with 15N. In general, fast‐growing fish are expected to have a better feed efficiency, and the results show that this is captured by isotope profiling in liver and muscle tissues. Furthermore, individual variation in isotope content, that is relative fraction of ‘new’ protein, among fish with comparable growth rates was observed, most expressed around ~50% isotope saturation, indicating differences in protein degradation and replacement not attributed to growth. The results suggest that isotope profiles can be used as individual indicator traits for feed efficiency and that inclusion levels of stable isotopes of 1%–2% gave the most reliable results. 相似文献
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The present paper gives an overview on the use of plant protein and plant oils as replacers for fish meal and fish oil in diets for Atlantic cod Gadus morhua L. In focus are effects on growth, feed utilization, digestibility, gut health, muscle and liver uptake and retention of nutrients, and muscle quality. Plant oil can replace fish oil without affecting growth provided that the requirement of marine long chain (LC) n‐3 fatty acids is met, but the altered dietary fatty acid profile in diet will be reflected in both muscle and liver. This can reduce the value of cod liver as an oil source for cod liver oil production. For the fish itself, there are more challenges replacing fish meal than fish oil, due to the amount of fibre and antinutrients in plant protein meals. However, A. cod seems to tolerate a wide range of plant types and their inclusion levels provided that the amino acids requirements are met. It is our view that there is sufficient knowledge to be able to design an A. cod diet based on a mixture of plant and marine ingredients and be able to predict performance such as growth, feed utilization, digestibility, liver size and fish health in general. 相似文献
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Sirirat Chatvijitkul Claude E. Boyd D. Allen Davis 《Journal of the World Aquaculture Society》2018,49(3):477-483
Nitrogen, phosphorus, and carbon concentrations were measured from 203 samples of starter, fingerling, and grower aquaculture feeds from several countries and for several common species. The feed protein concentrations reported by manufacturers often were slightly greater than the measured crude protein concentrations. The correlation coefficients (R2) between feed nitrogen and carbon concentrations were less than 0.50, and nitrogen and phosphorus concentrations in feed were not correlated. There were considerable differences in elemental concentrations among feeds, but the overall averages for carbon, nitrogen, and phosphorus concentrations, respectively, were as follows: starter feed 41.36, 7.78, and 1.57%; fingerling feed 39.75, 5.95, and 1.36%; grower feed 39.97, 5.36, and 1.22%. Concentrations of carbon, nitrogen, and phosphorus in feeds are required in estimating the pollution potential of aquaculture facilities. The crude protein concentration – if provided by the manufacturer – can be used to estimate nitrogen concentration in feed, but carbon and phosphorus concentrations should be measured. 相似文献
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大菱鲆幼鱼的蛋白质与能量需求 总被引：6，自引：0，他引：6
饲料中蛋白质的含量对大菱鲆幼鱼的生长起着决定性作用，适宜的能蛋比，既有利于能量的利用，又有利于蛋白质的利用，提高了饲料的利用率。设计4个蛋白质含量梯度和4个能量梯度的16组饲料，试验证明，蛋白质含量大于42％、能蛋比小于115，鱼体日增重率明显增大，饲料系数明显降低，表现出较高的饲料效率，本研究认为大菱鲆幼鱼配合饲料适宜的蛋白质含量为42％～45％、适宜的能蛋比为92．7～102．5。 相似文献
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鱼肉蛋白质挤压过程中操作参数对挤出物水分含量及堆积密度的影响 总被引：1，自引：0，他引：1
研究了鱼肉蛋白质在双轴挤压蒸煮处理过程中,主要操作参数末段腔体温度,螺杆转速和供料水分含量对挤出物的水分含量和堆积密度两个物理性质的影响。研究的3个操作参数每一个变量设5个水平,测量相应挤出产物的水分含量和堆积密度,分别建立挤出物水分含量与操作参数,挤出物堆积密度与操作参数的回归拟合方程。结果表明,供料湿度明显影响挤出物的水分含量。供料水分含量、腔体温度和螺杆转速对挤出物的堆积密度都有影响;水分含量与操作参数,堆积密度与操作参数的回归拟合方程的相关系数R2分别是1.000和0.926,拟合的统计模型可信度高。 相似文献
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Atlantic halibut (Hippoglossus hippoglossus) achieve a mature gastrointestinal tract approximately 2 months after first feeding (12 °C). The immature digestion may be the reason that compound diets fail to sustain growth and survival in first feeding halibut larvae and in larvae of other marine fish species. On the other hand, larvae fed with live feeds are capable of extraction of sufficient quantities of nutrients to sustain high growth rates. A lower availability of the protein in formulated diets compared with live prey is considered to be an important reason for the low performance of formulated diets. One approach to increase dietary protein availability is supplementation of pre‐digested proteins. Experiments using tube fed individual larvae show that halibut larvae are able to utilize hydrolysed protein more efficiently than intact protein. However, Atlantic halibut in culture did not respond well to dietary supplementation of hydrolysed protein, in contrast to some other species. One reason may be extensive leaching of pre‐hydrolysed proteins from the microparticulate feed. Atlantic halibut are slow feeders and may thus suffer more from nutrient leaching than species eating more rapidly. Feed formulation techniques affect dietary protein leaching, and in this paper, different techniques and their impact on feed properties are described. Microbound diets are most widely used in larval rearing, but show high rates of nutrient leaching. Lipid‐based capsules seem to have the best potential to prevent leaching, however, they are not able to deliver a complete diet. The high need for improvements in larval feed formulation techniques are clearly stated, and some suggestions are given. Among these are production of complex particles, where small lipid‐based capsules or liposomes containing the low molecular weight water‐soluble nutrients are embedded. In such feed particles the water‐soluble molecules are protected from leaching. Techniques for delivery of water‐soluble nutrients that are needed in large quantities, i.e. free amino acids or hydrolysed and water‐soluble protein, remain to be developed. 相似文献
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Anders Aksnes Britt Hope Øistein Høstmark Sissel Albrektsen 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):1102-1110
Fish hydrolysate was evaluated as feed ingredient in high plant protein diets in an 89 days feed experiment with Atlantic cod (Gadus morhua). The fish hydrolysate was size fractionated by ultra- and nano-filtration and the various fractions were tested specifically as feed ingredients to trace any effect observed with the hydrolysate. All diets contained 68% of total protein as plant protein, added as a mixture of corn gluten, full-fat soy bean meal, soy protein concentrate and extracted soy bean meal. The diets were equal in protein, lipid and energy. The control diet contained 21.8% fish meal. Fish hydrolysate was tested in another diet where one third of the fish meal protein was exchanged with the fish hydrolysate. Retentate after ultra-filtration of fish hydrolysate and retentate and permeate after nano-filtration were used in three separate diets at dietary inclusion levels corresponding to the absolute dry matter level of the fractions in the hydrolysate. The cod tripled in weight during the experimental period. No significant differences were observed for growth or feed intake for any groups. The diets containing retentate from ultra- and nano-filtration showed lower feed efficiency than the control diet with fish meal or the diet containing fish hydrolysate or permeate after nano-filtration. In conclusion the results show that fish hydrolysate may successfully be used as a protein source in high plant protein diets for Atlantic cod in exchange of fish meal. Removal of small molecules from the fish hydrolysate by filtration reveals poorer feed utilization indicating that this marine fraction of small compounds is important for optimal growth of Atlantic cod. This may be important in the discussion of increased dietary utilization of plant protein sources in feed for fish. 相似文献
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动植物蛋白源替代鱼粉研究进展 总被引：42，自引：5，他引：37
With the fast development of aquaculture, fish meal needs increased in recent years, however the quantity of fish catching decreases gradually. Fishmeal is a limited feed resource, and serious concem exists on the future availability of this feedstuff for incorporation in fish diets. Undoubtedly, fish meal is well recognized as the best dietary protein source for most marine carnivorous fishes which required high dietary protein levels compared to omnivorous or herbivorous fish. Fishmeal is known for their high content of essential amino acids and fatty acids, low carbohydrates, high digestibility, low levels of anti-nutritional factors (for fresh fish meal) and is a very good source of minerals and is highly palatable. Thus fish meal is in high demand as the protein source for many formulated diets. However, production of fish meal consumes approximately 35 % of the total global fish catch, and the increasing price and potentially unstable supply in the market could be limiting factors for marine fish culture. There have been strong efforts to define and develop cost-effective protein sources that can, at least partly, substitute for expensive high-quality fish meals in least-cost feed formulations. The search for fish meal substitutes and altemative dietary protein sources is an international research priority that could be of considerable economic advantages. Therefore it is urgent task to find animal and plant protein sources in place of fish meal. Among these, plant feedstuffs have received most attention in recent years, but due to their amino acid unbalances, .presence of anti-nutritional factors and low palatability, a high level of replacement of fish meal with plant feedstuffs in omnivorous fish is generally not well accepted. This paper reviews the research status for other protein sources replacing fish meal based on available information in the literature. Animal and plant protein sources nutrient values are evaluated from the aspect of digestibility, antinutrients, physiological status and suitable supplementation. 相似文献