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21.
多溴联苯醚(PBDEs)作为一种典型的持久性有机污染物,对海洋生物和生态系统的可持续性构成严重威胁。以2,2’,4,4’-四溴联苯醚(BDE-47)作为胁迫因子,以褶皱臂尾轮虫(Branchionus plicatilis)作为受试生物,基于代谢组学技术探讨褶皱臂尾轮虫应对BDE-47胁迫时的能量代谢变化。24 h胁迫实验的结果表明:褶皱臂尾轮虫的滤水率(F)和摄食率(G)显著降低,抑制了其对能源物质的获取;褶皱臂尾轮虫α-淀粉酶、脂肪酶、胰蛋白酶活性均受到抑制,降低了其对能源物质的消化效率;褶皱臂尾轮虫的总腺苷酸含量(TAP)随着BDE-47胁迫浓度的增加而不断下降,其能量状态发生了不利变化;褶皱臂尾轮虫的细胞能量分配(CEA)降低,是能量储备(Ea)减少和能量消耗(Ec)增加共同作用的结果。代谢组学分析表明褶皱臂尾轮虫的氨基酸代谢、脂质代谢和糖代谢产生了显著变化,发现了与氨基酸代谢、脂质代谢和糖代谢相关的26种差异代谢物和20条代谢通路,氨基酸、脂肪酸以及果糖水平显著下调,溶血磷脂酰胆碱(lysoPC)和磷酸乙醇胺(PE)显著上调。以上结果表明,BDE-47急性毒性胁迫影响了褶皱臂... 相似文献
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褶臂尾轮虫(Brachionus plicatilis O.F. Müller，以下简称Bp)和圆形臂尾轮虫(B.rotundiformis Tschugunoff，简称Br)(Segers，1995)是轮虫门(Rotifera)单卵巢纲(Monogononta)的两个海水种或半咸水种，过去曾分别被认为是褶皱臂尾轮虫的L型和S型品系，现统称为褶皱臂尾轮虫复合种(B.plicatilis complex)(Yufera，2001)。由于该种分布广，在世界范围内被广泛用作多种海水鱼的种苗培育的重要开口饵料，因而成为单卵巢纲中最具经济意义和极受各国研究者关注的种类。作为单卵巢纲轮虫的共同特征Bp和Br轮虫进行无性生殖(或孤雌生殖)兼有性生殖，两种生殖世代交替发生而完成其生活周期，休眠卵即是有性生殖的最终产物——卵膜加厚的受精卵(King et al，1977a，b；Snell，1987).在实际生产中，休眠卵是轮虫储存、运输和孵化应用的最理想形式；而在生物学意义上，它不仅是轮虫用以抵抗或度过不良环境期，并向新的生存空间散布或拓展的特殊生活阶段，而且可通过一定时间的休眠和一定条件下的孵化，决定着下一生活周期的起始，从而控制着轮虫生活周期的节奏。尤其是休眠卵经孵化而启动新一轮无性生殖世代，一方面承传和实现了前一世代的遗传特性和基因重组结果，另一方面也为轮虫的生殖表现和遗传特性得以在新环境下产生新的适应性变化提供了条件。鉴于上述重要的实际和理论意义，多年来对休眠卵的休眠与孵化的研究深受各国学者的重视。Gilbert(1974)、 Pourriot等(1983)已就国际上的有关研究进行了详细综述，最近席贻龙等(1999)结合国内的有关报道对该领域的进展亦作了进一步概括。这些论述均泛指单卵巢纲诸多种类的休眠与孵化问题，且多数结果来自淡水轮虫的研究。本文的讨论将主要针对海水或半咸水的褶皱臂尾轮虫复合种，就有关调控或影响其休眠卵孵化的各种内、外因子及其作用机理的研究概况作一综述。 相似文献
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The impacts of Prorocentrum donghaiense Lu and Alexandrium catenella Balech, causative species of the large-scale HAB in the East China Sea, were studied under laboratory conditions. According to bloom densities, the effects of monoculture and mixture of the two species were examined on the egg-hatching success of Argopecten irradians Lamarck, and the population growth of Brachionus plicatilis Müller and Moina mongolica Daday. The results showed that monoculture of A. catenella had a significant inhibition on the egg hatching success of A. irradians, and the population growth of B. plicatilis and M. mongolica. The median effective densities (ED_50) inhibiting the egg hatching success of A. irradians for 24 h and the population growth of B. plicatilis and M. mongolica for 96 h were 800, 630, and 2 400 cells/cm3, respectively. Monoculture of P. donghaiense has no such inhibitory effect on the egg hatching success of A. irradians; P. donghaiense at lower suitable densities could sustain the population growth of B. plicatilis (1×104~3×104cells/cm3) and M. mongolica (2×104~5×104cells/cm3); P. donghaiense at higher densities had significantly adverse effect on the population growth of B. plicatilis (4×104~10×104cells/cm3) and M. mongolica (10×104cells/cm3). When the two algae were mixed according to bloom densities, P. donghaiense at suitable densities to some extent could decrease the toxicity of A. catenella to B. plicatilis and M. mongolica. The results indicated that the large-scale HAB in the East China Sea could have adverse effect on zooplankton, and might further influence the marine ecosystem, especially when there was also Alexandrium bloom. 相似文献
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Effect of UV-B radiation on the feeding behavior of the rotifer Brachionus plicatilis 总被引：3，自引：0，他引：3
Effect of UV-B radiation on the feeding behaviour of marine zooplankton is important to assessing the health harm of marine ecosystem due to the gradually enhanced UV-B radiation in air. However, there are a few studies on this topic. The feeding behavior of the rotifer, Brachionus plicatilis, under the treatment of UV-B radiation on five species of microalgae, i.e., Chlorella sp., Tetraselmis chuii, Isochrysis galbana Park 8701, Chaetoceros muelleri Lermumerman, and Nitzschia clostertum, was studied. The results showed that the filtering and feeding rates of the rotifer decreased significantly with the dose increase of UV-B radiation when fed with five species of microalgae respectively (P<0.05) which indicates UV-B radiation inhibits the feeding activities of the rotifer on microalage. The mixed culture experiments shows the rotifer preferred to feed Chlorella sp., then C. muelleri,I. galbana, N. clostertum and T. chuii in turn if without UV-B radiation. Under the highest dose of UV-B radiation treatment (2.70 kJ/m2), the rotifer preferred to feed C. muelleri, then Chlorella sp., N. clostertum, I. galbana and T. chuii in turn. Chlorella sp., I. galbana and C. muelleri became the more favorite foods of the rotifer while T. chuii and N. clostertum became less favorite foods. The change of feeding rate and feeding selectivity of zooplankton driven by the enhanced UV-B radiation will lead to the change in the structure of phytoplankton community. 相似文献
25.
光合细菌对褶皱臂尾轮虫的饵料价值 总被引：3，自引：0，他引：3
我们自青岛栈桥浅海海泥中分离到一株光合细菌,经鉴定为球形红假单胞菌(Rhodopseudomonas spheroides)。对其生化特性、生长条件以及做为褶皱臂尾轮虫(Brachionus plicatilis)的饵料价值,进行了研究。结果表明,以球形红假单胞菌的新鲜培养物,混以青岛大扁藻(Platymonas helgolandica var.tsingtaoensis)喂养轮虫,轮虫的增殖率明显高于单独使用光合细菌、扁藻和海洋酵母,也高于光合细菌与海洋酵母的混合。提示在轮虫的生产性培养中,以一定浓度的光合细菌与单胞藻混合投喂轮虫,可能取得较高产量。 相似文献
26.
4种重金属离子及其混合液对壶状臂尾轮虫的急性毒性试验 总被引：3，自引：0，他引：3
研究了铜、锌、镉、铅离子及其混合液对壶状臂尾轮虫(Brachionusurceus)的急性毒性影响,实验结果表明,Cu2+、Zn2+、Cd2+、Pb2+对壶状臂尾轮虫的24hLC50分别为83 .18μg/L、4 .27mg/L、7. 60mg/L、23 44mg/L,将4种离子按照质量比120∶20∶6∶1的比例配成混合金属溶液,其混合液对壶状臂尾轮虫的24hLC50为0 42mg/L。 相似文献
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We tested the effect of two algal diets (Chlorella vulgaris at 1 · 106 cells mL?1and Scenedesmus acutus at 0.57 · 106 cells mL?1) offered alone or in combination (50 % each, 75 % or 25 % of either alga), at a total dry weight of 14.2 μg mL?1on the life table demography of two rotifer species, Brachionus calyciflorus and Brachionus patulus. Data on fecundity indicated that, for any given algal food type or combination of food types, B. calyciflorus had a higher rate of offspring production than B. patulus. Regardless of the rotifer species, the average lifespan varied from 4 to 6 days. The gross and net reproductive rates were higher for B. calyciflorus than for B. patulus. These values ranged from 45 to 71 offspring female?1 lifespan?1 and 15 to 24 offspring female?1 lifespan?1, respectively, for B. calyciflorus. Generation times (around 4…5 days) were similar for both rotifer species in most of the treatments. Whatever the algal food combination, the rate of population increase (d?1) of B. patulus was less than half (i.e. 45 %) of that for B. calyciflorus. The observed differences in the life history variables of Brachionus probably explain species‐specific adaptations to the changing phytoplankton composition occurring seasonally in natural waterbodies. 相似文献
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5种淡水浮游藻对萼花臂尾轮虫饵料效果的比较研究──藻的最适投喂密度及轮虫相应的种群增长 总被引：1，自引：0，他引：1
于1993年9月在山东省胶南市鱼苗繁殖地池塘采得萼花臂尾轮虫,采用种群累积培养法,对其摄食5种淡水浮游藻的最适密度及其相应的种群增长进行研究。结果表明,该轮虫摄食这5种藻的最适密度（×106cell／ml）分别是：蛋白核小球藻,45;斜生栅藻,25;小球衣藻,5;卵形隐藻,0．2;中型裸藻,0．1。导出了藻的细胞大小（x）和最适投喂密度（y）之间的回归方程为：y＝－15．5＋216／x（r＝0．9826,P＜0．01）。在5种藻的最适密度下比较了投喂轮虫的饵料效果,结果是,5种藻中以蛋白核小球藻和斜生栅藻为最优,其它依次为卵形隐藻、小球衣藻和中型裸藻。据此,认为蛋白核小球藻和斜生栅藻是该轮虫批量培养乃至工厂化培养的首选饵料。 相似文献
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不同地理区域湖泊中萼花臂尾轮虫的生活史特征 总被引：2，自引：2，他引：0
以3.0×106cells/ml的斜生栅藻(Scenedesmus obliquus)为食物,应用生命表统计学等方法比较研究了于2008年冬季采自芜湖市汀棠湖和广州市荔湾湖的萼花臂尾轮虫(Brachionus calyciflorus)在不同温度(10℃、15℃和20℃)下的生活史特征.结果显示,10℃下,芜湖种群除内禀增长率外的其他各生命表统计学参数均显著大于广州种群.15℃下,芜湖种群仅世代时间和后代混交率显著大于广州种群.20℃下,芜湖种群的世代时间和后代混交率显著大于广州种群,而总生殖率、净生殖率和内禀增长率则相反.两地理种群轮虫出生时的生命期望、世代时间和平均寿命均随温度的升高而逐渐显著地缩短,内禀增长率随温度的升高而逐渐显著地增大;但缩短或增大的速率在两地理种群间存在着差异.芜湖种群的总生殖率和净生殖率不受温度的显著影响;而广州种群的总生殖率随温度升高而逐渐显著地增大,净生殖率在20℃和15℃下无显著差异,但都显著高于10℃下.芜湖种群的后代混交率在10℃下显著高于20℃下,但均与15℃间无显著性差异;广州种群的后代混交率随温度的升高而逐渐显著地增大.两地理种群内禀增长率间的差异可能与各自对所栖息的水环境年平均温度的长期适应有关,而后代混交率间的差异则是它们对水温季节变化长期适应的结果. 相似文献