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81.
82.
比较研究了卯形鲳够(Trachinotus ovatus)成鱼和幼鱼阶段消化酶(蛋白酶、淀粉酶、脂肪酶)在不同消化器官中的活性。结果表明:1)成鱼蛋白酶在不同消化器官中的活性大小依次为胃〉前肠〉中肠〉幽门盲囊〉后肠〉肝;淀粉酶活性为前肠〉后肠〉幽门盲囊〉中肠〉肝〉胃;脂肪酶活性为前肠〉中肠〉后肠〉幽门盲囊〉肝〉胃。2)幼鱼蛋白酶在不同消化器官中的活性大小依次为胃〉肠〉幽门盲囊〉肝;淀粉酶活性为肠〉幽门盲囊〉肝〉胃;脂肪酶活性为肠〉幽门盲囊〉肝〉胃。3)成鱼不同消化器官中蛋白酶和淀粉酶的活性均小于幼鱼,成鱼胃和幽门盲囊的淀粉酶活性与幼鱼的差异显著;幼鱼胃脂肪酶活性大于成鱼,但其他器官的活性均小于成鱼。卵形鲳鳕幼鱼不同消化器官中的3种消化酶活性大小顺序与成鱼基本相似。 相似文献
83.
Linking spatial pattern of bottom fish assemblages with water masses in the North Sea 总被引:2,自引:0,他引:2
Understanding the links between large scale spatial structuring of fish assemblages and shaping factors is essential to develop comprehensive ecosystem-based fisheries management. In this study, we investigated spatial patterns of bottom fish assemblages in the North Sea in relation to prevailing water masses in the region. We based our analysis on catch data from the German Small-Scale Bottom Trawl Survey conducted between 1987 and 2005 and used both ordination techniques and Mantel tests. Spatial variability of bottom fish assemblages was larger than inter-annual variability. Five significantly different bottom fish assemblages were associated with the following prevailing hydrographical regimes: i) the English Channel, ii) Continental Coastal, iii) central North Sea, iv) northern North Sea, and v) northern Atlantic water masses. Associations were generated by gradients in relative proportions of abundant species such as grey gurnard ( Eutrigla gurnardus ), dab ( Limanda limanda ), whiting ( Merlangius merlangus ), haddock ( Melanogrammus aeglefinus ) and Norway pout ( Trisopterus esmarki ). Taking into account large scale spatial structuring of catch data Mantel tests confirmed significant correlation between the fish assemblages and hydrographical variables. In summary, our results strongly support the hypotheses that hydrographical features such as water masses, fronts, and residual currents could shape bottom fish associations in the North Sea. Spatial demarcations of bottom fish assemblages indicated by this study can be used to support ecosystem-based fisheries management strategies. 相似文献
84.
85.
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
86.
87.
Kazufumi?OsakoEmail author Mohammed?Anwar?Hossain Koichi?Kuwahara Akira?Okamoto Atsuko?Yamaguchi Yukinori?Nozaki 《Fisheries Science》2005,71(6):1347-1355
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
88.
89.
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
90.
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