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1.
分别在基础饲料(对照组)中添加100 mg/kg的虾青素、角黄素,混合色素(50 mg/kg虾青素+50 mg/kg角黄素)饲喂初始体重为(56.60±0.63) g的虹鳟60 d,考察虾青素和角黄素对虹鳟肌肉着色和肝脏总抗氧化能力的影响。结果显示,饲料中添加了虾青素、角黄素和混合色素后对虹鳟增重率、饲料系数及肌肉常规成分、肌肉失水率、含肉率均无显著影响(P> 0.05)。虾青素组、角黄素组和混合色素组虹鳟肌肉的比色卡得分、红度、虾青素含量和血清总类胡萝卜素含量均比对照组有显著提高(P< 0.05);虾青素组虹鳟肌肉比色卡得分(26.25)和红度值(18.40)显著高于角黄素组(22.38, 14.13)和混合色素组(24.00, 15.70)(P< 0.05);虾青素组虹鳟肌肉虾青素含量为4.75 mg/kg (30 d)和6.45 mg/kg (60 d),均显著高于混合色素组的3.87 mg/kg (30 d)和5.48 mg/kg (60 d)(P< 0.05);在虹鳟血清总类胡萝卜素含量方面,虾青素组 > 混合色素组 > 角黄素组;虾青素组、角黄素组、混合色素组虹鳟肝脏的总抗氧化能力之间无显著差异(P> 0.05),分别为2.39 U/mg,2.25 U/mg,2.39 U/mg,均较对照组(2.03 U/mg)显著提高(P< 0.05)。上述结果表明:饲料中添加100 mg/kg虾青素、角黄素及虾青素+角黄素混合(1∶1)均能有效改善虹鳟肌肉颜色,提高肝脏总抗氧化能力,虾青素、虾青素+角黄素混合(1∶1)对虹鳟肌肉的着色效果优于角黄素。  相似文献   

2.
本文目的旨在研究虾青素对微囊藻毒素MC-LR胁迫下(25μg/L)克氏原螯虾的免疫力及生长繁殖的影响。实验设计四个梯度的饲料中虾青素添加比例分别为(0、5、10、20 mg/g)养殖周期持续8星期。结果表明虾青素显著提高了克氏原螯虾肝脏中超氧化物歧化酶(SOD)和碱性磷酸(AKP)的活力(P0.05)。5g/kg虾青素的添加量即可对SOD酶活具有明显提升(P0.05);10 g/kg的虾青素添加量对AKP的提升最为明显(P0.05);研究还发现虾青素可显著提高微囊藻毒素MC-LR胁迫下克氏原螯虾的存活率和特定生长率(SGR)(P0.05),提高克氏原螯虾雌虾的抱卵量。研究表明虾青素作为一种抗氧化剂适宜于在克氏原螯虾饲料中添加,并且具有提高虾体免疫活力,缓解微囊藻毒素MC-LR对虾体氧化胁迫的作用。  相似文献   

3.
毛连环 《河北渔业》2020,(4):1-3,19
通过对赤点石斑鱼(Epinephelus akaara)亲本强化、苗种繁育阶段的饵料进行研究,结果表明:采用牡蛎作为赤点石斑鱼亲本营养强化饵料使得亲本成活率达89.33%,所产的卵子平均受精率达78.9%、孵化率达80.1%,均显著高于使用南美白对虾和蛏子组(P<0.05);苗种培育至摄氏卤虫阶段,采用鱼油(4 g/L)与经小球藻强化轮虫和虾青素(5 g/L)混合代替,成活率29.53%,全长增长率175.00%,效果最佳;苗种培育至摄氏桡足类阶段,采用鱼油(4 g/L)与桡足类和虾青素(5 g/L)培育,成活率和全长增长率均显著高于其他组(P<0.05);而后期采用软颗粒料(鳗粉:鳀鱼=3:2,添加虾青素5 g/kg)可极显著提高赤点石斑鱼的养成成活率和全长增长率(P<0.01)。  相似文献   

4.
为减缓虾青素的氧化速度,提高虾青素的储藏稳定性,以麦芽糊精、羟丙基-β-环糊精(HP-β-CD)为壁材,采用喷雾干燥法对南极磷虾(Euphausia superba)虾青素进行微胶囊化包埋,并对微胶囊化后产品的理化性质进行研究。结果显示,麦芽糊精与HP-β-CD壁材质量比为1∶3、虾青素添加质量分数为4.76%、聚山梨酯-80添加质量分数为0.87%、固形物浓度为0.20 g/ml时,虾青素微胶囊包埋率为98.77%。制备的虾青素微胶囊水分含量为(3.11±0.11)%,溶解度为(94.32±0.08)%,休止角为(34.16±0.24)°。稳定性实验表明,与未微胶囊化的虾青素晶体相比,虾青素微胶囊在高温条件、自然光条件与有氧条件下,虾青素的保留率分别由28.72%、45.27%与20.76%提高到了78.32%、84.88%和74.97%。可见微胶囊化可明显改善虾青素溶解性和稳定性,为虾青素微胶囊化产品制备提供技术支持。  相似文献   

5.
以贵州草海自然水域捕获的新鲜小龙虾(Procambarus clarkii)为材料,采用单因素实验研究了提取溶液、料液比、提取温度、提取时间、提取次数对虾青素提取效果的影响,用分光光度法测定了草海小龙虾不同部位虾青素的含量。结果表明,以乙酸乙酯为提取溶液,料液比为1∶2(g∶mL),在60℃下提取2 h,重复提取两次,再此提取条件下虾壳中虾青素含量最高。在虾壳、虾肉和内脏三个部位中,虾壳中虾青素含量最高,虾肉和内脏中也含有少量虾青素,但是含量远低于虾壳中的含量,说明了小龙虾虾青素主要富集在虾壳中。  相似文献   

6.
<正>虾青素又名虾黄素,抗氧化能力极强,是一种粉红色天然色素,具有清除自由基作用,可提高动物机体免疫力,有良好的着色效果。天然虾青素常存在于某些动物、藻类及微生物体内。雨生红球藻(Haematococcus Pluvialis)是近年来被研究最多,也是被公认为自然界中天然虾青素的积累以及应用于水产动物中的最佳来源之一,其虾青素积累速率和产生总量较其他绿藻高,虾青素的含量可高达细胞干重的4%,是目前所知虾青素含量最高的一种生物体,被看作是天然虾青素的"浓缩品"。植物生长激素不仅对高等植物的生长发育有着明显的促进效果,而且在农业生产领域上也有  相似文献   

7.
虾青素(astaxanthin),又名虾黄质、龙虾壳色素。虾青素的化学结构为长链不饱和双键结构体系,因此性质不稳定,易于异构化和降解。虾青素对热、氧、自然光、紫外照射敏感,加热、光照以及酸、碱等条件都会引起虾青素的异构化。虾青素与脂肪酸结合形成的酯要比游离虾青素稳定得多,而且虾  相似文献   

8.
水温12~18℃,将体质量(435.63±21.32) g的哲罗鲑饲养在6.0 m×2.5 m×1.2 m的流水水泥池中,投喂含100 mg/kg人工合成虾青素(对照组)和10、20、40、60 mg/kg天然虾青素(雨生红球藻)饲料,每两周检测试验鱼肌肉中的虾青素含量和鳃、肝脏、前肠、后肠、幽门垂、肌肉、血清、血细胞的总抗氧化能力和碱性磷酸酶活性,研究人工合成虾青素和天然虾青素对肌肉中虾青素含量及其组织抗氧化力的影响。70 d的饲养结果显示:(1)与对照组相比,20 mg/kg和40 mg/kg组的试验鱼虾青素含量显著升高(P0.05),且40 mg/kg含量组试验鱼虾青素含量显著优于20 mg/kg组(P0.05);(2)各组试验鱼鳃、肝脏、前肠、后肠、幽门垂、血清、血细胞的总抗氧化能力显著高于对照组(P0.05);(3)各组试验鱼鳃、后肠、幽门垂、肌肉、血清、血细胞的碱性磷酸酶活性显著高于对照组(P0.05)。试验结果表明,与添加100 mg/kg人工合成虾青素相比,饲料中添加20~40 mg/kg天然虾青素,能显著提高哲罗鲑肌肉虾青素含量、总抗氧化能力以及碱性磷酸酶活性,建议哲罗鲑饲料中天然虾青素添加量为40 mg/kg。  相似文献   

9.
虾青素生物学来源和功能的研究进展   总被引:16,自引:0,他引:16  
董玉华  赵元凤 《水产科学》2005,24(10):50-52
虾青素(Astaxanthin)即3,3’—二羟基-4,4’二酮基-β,β’胡萝卜素,又称虾黄质、虾黄素、龙虾壳色素、还原型虾红素。虾青素的分子式为C40H52O4,是一种萜烯类非维生素A源胡萝卜素,呈艳丽的红色,易溶于二硫化碳、丙酮、苯和氯仿,因其具有着色功能和极强的抗氧化性,提高免疫力;近年来越来越受到国内外食品、医药、化妆品、养殖、饲料等领域研究人员的重视。1虾青素的生物学来源虾青素在动物体内和羽毛中,尤其是水生动物体内(如虾、蟹)普遍存在。早在20世纪30年代虾青素就已从虾、蟹中分离出来。除了从水产品加工的废弃物中提取虾青素外,从…  相似文献   

10.
以26S rDNA法将实验室保藏的1株产虾青素的海洋酵母菌YS-185鉴定为粘红酵母。以海洋酵母菌YS-185为试验菌株,运用摇瓶发酵优化的方式,探索培养基组分和发酵工艺条件对该菌发酵的影响。实验结果表明,该菌生长最适培养基组分为葡萄糖8 g/L、蛋白胨8 g/L,最适生长起始pH值为5.5、转速220 r/min、接种量8%、温度20℃;虾青素合成的最佳培养基组分葡萄糖8 g/L、蛋白胨8 g/L,最佳虾青素合成条件:pH 5.5,转速220 r/min,接种量8%,培养温度25℃。发酵优化后的虾青素产量2.670μg/ml,较优化前的1.572μg/ml提高了69.8%。温度对酵母菌的生长和虾青素的合成都有显著影响。海洋酵母菌YS-185优化后的发酵条件有规模化生产虾青素的应用潜力。  相似文献   

11.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

12.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

13.
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.  相似文献   

14.
Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.  相似文献   

15.
This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO2 and ions should be more often evaluated. Plasma Na+ and Cl are very useful markers of acidosis, due to their respective exchange for H+ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.  相似文献   

16.
Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.  相似文献   

17.
The toxic effects of Cd2+ on Ca2+ influx kinetics in developing tilapia (Oreochromis mossambicus) larvae were evaluated. Addition of 20 µg l-1 of Cd2+ to the environment of 0 and 3 day-old larvae competitively inhibited the Ca2+ uptake within 4h resulting in a great increase in Km values for Ca2+ influx (19.3 and 17.4 fold, respectively) as compared with their respective controls. Consequently, the actual Ca2+ influx of larvae in solutions of 0.2 mM Ca2+ are suppressed by 32–45%. Also, 3 day-old larvae were more sensitive to internally accumulated Cd2+ than 0 day-old larvae. Although the Ca2+ influx in 0 and 3 day-old larvae may be restored to the levels of their respective controls with 24h of being transferred to a 20 µg l-1 Cd2+ solution, total body Ca2+ content was significantly reduced in 3 day-old larvae. Increased Ca2+ uptake efficiency ensures sufficient Ca2+ for normal growth. However, rapid increase in Ca2+ influx after hatching also leads to higher Cd2+ uptake. Exposure to Cd2+ will lead to a drop in body Ca2+ content resulting in retardation of larval growth. Therefore, we conclude that if Ca2+ uptake is interfered with at this critical stage of development, larvae will not be able to maintain normal levels of body Ca2+ and will show signs of Cd2+ poisoning.  相似文献   

18.
Migratory dynamics of stream-spawning longnose gar (Lepisosteus osseus)   总被引:1,自引:1,他引:0  
Abstract– Literature evidence suggests that lake-dwelling longnose gar (Lepisosteus osseus) enter tributary streams to spawn, Until the present study, the dynamics of this breeding migration had never been investigated quantitatively. During the summers of 1991 and 1992, longnose gar were captured as they entered Weaubleau Creek, Missouri, a tributary of Harry S. Truman Reservoir. The in-stream spawning migration began in early April and ended in late May, and was positively correlated with stream flow and water level, and negatively correlated with water temperature. In-stream residence times ranged from 15 to 94 days, with males exhibiting longer residence times than females. Once in-stream, longnose gar travelled as far as 10 km upstream and occupied certain pools at greater relative frequencies. Although the reason for this preferential utilization is not completely understood, it may relate to pool depth and riffle proximity. Longnose gar disperse from the spawning stream great distances, with gar captured in Weaubleau Creek being recaptured up to 48 km away. This information should provide fisheries biologists the means to consider the reproductive ecology of this species in their conservation and management decisions.  相似文献   

19.
The desaturation and elongation of [1-14C]18:3n-3 was investigated in hepatocytes of the tropical warm freshwater species, zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus). The hepatocyte fatty acid desaturation/elongation pathway was assayed before and after the fish were fed two experimental diets, a control diet containing fish oil (FO) and a diet containing vegetable oil (VO; a blend of olive, linseed and high oleic acid sunflower oils) for 10 weeks. The VO diet was formulated to provide 1% each of 18:2n-6 and 18:3n-3, and so satisfy the possible EFA requirements of zebrafish and tilapia. At the end of the dietary trial, the lipid and fatty acid composition was determined in whole zebrafish, and liver, white muscle and brain of tilapia. Both zebrafish and tilapia expressed a hepatocyte fatty acid desaturation/elongation pattern consistent with them being freshwater and planktonivorous fish. The data also showed that hepatic fatty acid desaturation/elongation was nutritionally regulated with the activities being higher in fish fed the VO diet compared to fish fed the FO diet. In zebrafish, the main effect of the VO diet was increased fatty acid Δ6 desaturase activity resulting in the production of significantly more 18:4n-3 compared to fish fed the FO diet. In tilapia, all activities in the pathway were greater in fish fed the VO diet resulting in increased amounts of all fatty acids in the pathway, but primarily eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). However, the fatty acid compositional data indicated that despite increased activity, desaturation of 18:3n-3 was insufficient to maintain tissue proportions of EPA and DHA in fish fed the VO diet at the same level as in fish fed the FO diet. Practically, these results indicate that manipulation of tilapia diets in commercial culture in response to the declining global fish oil market would have important consequences for fish fatty acid composition and the health of consumers. Scientifically, zebrafish and tilapia, both the subject of active genome mapping projects, could be useful models for studies of lipid and fatty acid metabolism at a molecular biological and genetic level. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Controlled incorporation of selected microalgae and bacteria in aquaculture systems can be beneficial because they can act as microbiological control. That is why the characteristics of biofilm generated naturally in Seriola lalandi culture cages were analysed, their potential benefit to the growth of larvae was studied, and their controlled use for improving the larval viability and as a vector to improve incorporation of previously studied probiotic bacteria was tested. According to biodiversity results, these biofilms are composed of a diatom–bacteria mix showing a decrease in biodiversity in laboratory culture conditions being dominated by Navicula phyllepta and bacteria of the family Rhodobacteraceae. This can be produced on mesh substrates incorporated in bioreactors with rapid growth rate and adhesiveness. Preliminary results from the addition of substrates with this specific biofilm in larvae culture systems showed that it is consumed by the larvae without negative effects, while positive effects on the viability of larvae in combination with probiotics were observed. Considering preliminary results, the addition of these specific substrates with diatom–bacteria biofilms could be a good improvement for aquaculture systems and together with the use of probiotics can contribute to maintaining a stable and controlled system improving the viability of the larval fish culture in its early stages.  相似文献   

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