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71.
海南岛近岸海域鱼类物种组成和多样性的季节变动   总被引:2,自引:0,他引:2  
根据2006年~2007年间在海南岛近岸海域进行的4个航次底拖网调查资料,分析了该海域鱼类物种组成和生物多样性特征。发现该海域鱼类种类较为丰富,调查共采集到鱼类292种,隶属于21目100科172属;其中暖水性种类数占83.32%,暖温性种类数占16.78%;与中国黄渤海共有种76种,与东海共有种220种,与南海大陆架、大陆坡和南海诸岛海域共有种分别为279种、42种和51种。鱼类优势种[相对重要性指数(IRI)〉500]依次为发光鲷(Acropoma japonicum)、斑鳍天竺鱼(Apogonichthys carinatus)、黄斑鲾(Leiognathus bindus)、皮氏叫姑鱼(Johnius belengeri)、大头白姑鱼(Argyrosomus macrocephalus)、(Therapon theraps)、棕斑腹刺鲀(Gas-trophysus spadiceus)和麦氏犀鳕(Bregmaceros macclellandi)。以生物量为基础采用5个指数研究了该海域鱼类多样性现状,并采用季节更替指数(AI)和迁移指数(MI)对各季节鱼类群落的稳定性进行了分析。结果显示,该海域鱼类多样性水平较高,相邻季节的鱼类物种相似性也较高,随着鱼类的洄游,群落的稳定性出现较大波动。  相似文献   
72.
杜涛  罗杰  林向阳 《水产科学》2004,23(7):24-26
为建立一套海水鱼类人工育苗技术,分别采用室内水泥池、室外对虾高位池以及室内水泥池与室外对虾高位池相结合的育苗方法进行美国红鱼、花尾胡椒鲷等鱼类人工育苗试验。结果表明:室内水泥池育苗成活率为11%~98 8%,室外对虾高位池育苗成活率最高为6%,室内外相结合育苗的成活率为37 5%~73%。采用前期室内人工培育,幼苗体长约10mm移到室外对虾高位池培育,既可提高育苗成活率,又可降低育苗成本,是目前值得推广的育苗方法。  相似文献   
73.
ABSTRACT:   To explore the potential utility of underutilized fish in the fish sauce industry, fish sauces were prepared from both raw and heat-induced meat of Japanese anchovy Engraulis japonica and rabbit fish Siganus fuscescens using wheat malt, and their quality aspects and sensory properties were assessed. Proximate composition of the fish meat represents protein as the major component (16.0–17.8%), other than moisture. Analyses of free amino acids, peptides including oligopeptides, and organic acids contents in fish sauces revealed suitability of both raw and heat-induced meat of the selected species in commercial fish sauce production. The variations in taste of raw meat fish sauces were species-specific, but the taste of fish sauces from heat-induced meat were similar.  相似文献   
74.
75.
鱼肉酶解物及壳聚糖对鲤鱼涂膜保鲜效果的研究   总被引:1,自引:0,他引:1  
以感官评分、挥发性盐基氮、菌落总数、K值为指标,研究比较了鱼肉酶解物和壳聚糖为原料的涂膜液对鲤(Cyprinus carpio)(4℃)冷藏过程中品质变化的影响。结果显示:贮藏期间,对照组的感官评分显著低于各涂膜组(P<0.05)。贮藏前8 d,涂膜组能够显著抑制K值的升高(P<0.05)。鱼肉酶解物和壳聚糖涂膜组均能够显著抑制细菌的生长,而贮藏2~6 d内鱼肉酶解物涂膜鲤鱼的菌落总数显著低于壳聚糖涂膜组(P<0.05)。贮藏后期,鱼肉酶解物组能延缓TVB-N值的升高,壳聚糖涂膜组能够显著抑制TVB-N值的升高(P<0.05)。鱼肉酶解物可作为一种新的可食性涂膜材料,用于延长鲤鱼的贮藏期。  相似文献   
76.
Waterless live fish transportation is an alternative and promising transport strategy, which may reduce shipping costs, increase stocking density and improve survival of some species. Spotted sea bass is one of the most economically important marine fish in China. However, waterless transportation has not yet been studied on spotted sea bass. To explore the possibility of waterless transportation of spotted sea bass and its sublethal stress responses, the survival rate and dynamics of blood biochemical parameters were evaluated in the present study by preserving it under no water, less water and water (control) conditions for 9 hr. The serum biochemical parameters including total protein, cortisol, glucose, lactate, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total carbon dioxide (TCO2), creatinine, blood urea nitrogen (BUN), ammonia, superoxide dismutase (SOD) activity and malonaldehyde (MDA) were investigated. Results showed that the survival rates of fish in all groups gradually declined with time increasing. At the end of transportation, the survival rates in the control group, less‐water group and no‐water group decreased to 49.11%, 15.60% and 23.96% respectively. Significant changes were observed in several selected serum biochemical parameters, including glucose, lactate, ALT, TCO2, BUN and ammonia during simulated waterless transportation, which might negatively affect the physiological homeostasis of fish, leading to the high mortality in present study. In general, waterless transportation of spotted sea bass was possible, but it might be rather suitable for short time than long time.  相似文献   
77.
为了解赤水河的鱼类资源现状,于2010年5~6月和9~10月在赤水河赤水镇、赤水市和合江县的3个江段进行了渔获物调查工作。通过统计各江段的渔业捕捞情况,计算年捕捞量。采用体长股分析的方法,对云南光唇鱼(Acrossocheilus yunanensis)、大鳍鳠(Mystus macropterus)和张氏歺鱼又(Hemiculter tchangi)的资源量进行了估算,并以此推算各江段鱼类的总资源量。结果显示,赤水镇江段的鱼类年总资源量为10.76t,其中云南光唇鱼为1.23t;赤水市江段的年总资源量为  相似文献   
78.
A 30‐day experiment was conducted to evaluate the effect of C/N ratio on water quality and bacterial community in an integrated system comprising one molluscan species (pearl mussel Hyriopsis cumingii) and two fish species (gibel carp Carassius gibelio and silver carp Hypophthalmichthys molitrix) at five C/N ratios (6, 8, 10, 12 and 14). The mussel and fishes were reared in the experimental tanks (400 L), but gibel carp received formulated feed. Water quality in the experimental tanks was analysed on day 0, 10, 20 and 30, and bacterial community in the water column and sediment was analysed on day 30. Total nitrogen, total phosphorus and total organic carbon accumulated in the tanks over time. Ammonia and nitrite decreased with the increase in C/N ratio. Bacterial community in the water column and sediment changed at the phylum and genus levels with the increase in C/N ratio, and the critical C/N ratio causing a functional shift of bacterial community occurred at 10 in water column and 12 in sediment. The increase in C/N ratio benefited the growth of both potential probiotics and pathogenic bacteria. The high C/N ratio enhanced the bacterial functions of chemoheterotrophy and hydrocarbon degradation, but depressed the functions of nitrification and denitrification in the water column and sediment respectively. This study reveals that the C/N ratio can be used as a tool to manipulate the bacterial community and water quality in the mussel‐fish integrated system.  相似文献   
79.
The current high demand and cost of fish meal (FM) necessities the evaluation of alternative plant protein ingredients in diets of farmed marine fish. A 56‐day feeding trial was performed to study the effects of replacement of FM with soy protein concentrate (SPC) in diets of Acanthopagrus schlegelii. Diets were prepared at levels of 0%, 30%, 47.5%, 65%, 82.5% and 100% SPC, respectively, replacing FM. The results indicated no significant differences (p > .05) in % weight gain (WG) and specific growth rate of fish fed S30% to S82.5% diets compared with the control diet while, further inclusion at 100% significantly depressed growth performance. SPC inclusion and phytase supplementation significantly affected the phosphorous discharge (P‐load) showing lowest value (3.83 ± 0.53 g/kg WG) in S100% compared to control (14.79 ± 0.37 g/kg WG) and in fish fed S30% diet (13.24 ± 0.89 g/kg WG) (p < .05). The results of this study showed that FM could be substituted up to 82.5% by SPC in the diet of Acanthopagrus schlegelii fingerlings (5.53 ± 0.12 g) without any adverse effects. Phytase supplementation SPC based diets could be effective in reducing the phosphorus load in the aquatic culture environment.  相似文献   
80.
刘念  黄琪琳  李沛  郭江勇  覃先武 《水产学报》2021,45(7):1089-1100
为探究添加不同种类酵母抽提物对生鲜鱼片风味及质构的影响,实验以调理乌鳢鱼片为原料,通过同时蒸馏萃取法(SDE)提取挥发性成分,利用GC-MS联合电子鼻、电子舌对6组调理乌鳢鱼片(空白对照CK组、FA02组、KU012组、FG10组、FA39组和F55组)进行风味成分分析,再结合感官、色度和质构进一步评价了6组调理乌鳢鱼片的品质。结果显示,CK组检测出42种挥发性物质,而添加5种酵母抽提物后(FA02、KU012、FG10、FA39、F55),挥发性物质的种类显著增多,分别为60、66、56、52、46种。鱼片中主要特征挥发性物质为醛类,如庚醛、癸醛以及(E, E)-2, 4-癸二烯醛等;添加不同种类酵母抽提物后,各组鱼片挥发性物质增加了(E)-4-癸烯醛、2-壬酮和3-壬烯-2-酮等。其中KU012组挥发性物质种类及含量增加最多,如具有清新气味的(E)-2-戊烯醛、黄瓜味的(E, Z)-2, 6-壬二烯醛以及提高整体风味的(Z)-2-(2-戊烯基)呋喃。电子鼻和电子舌的测定结果显示,各酵母抽提物组与CK组在气味、滋味方面存在显著差异。相对于CK组,添加酵母抽提物调理的乌鳢鱼片色泽呈浅黄,质构略有降低,但感官评分有所升高。研究表明,不同种类酵母抽提物均能一定程度改善调理乌鳢鱼片的风味、质构及感官品质,其中KU012组综合表现最佳。本研究为酵母抽提物在水产品中的调味应用提供了参考,具有实践价值。  相似文献   
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