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11.
Worldwide, most sea‐urchin populations are in decline. Future market demands will likely be met through aquaculture, which may consist of gonad enhancement of wild‐caught sea urchins. In this context, we examined three land‐based containment systems for suitability in maintaining commercial‐size green sea urchins (Strongylocentrotus droebachiensis). Mortality rate, gonad quantity, gonad quality (colour, brightness, firmness, texture) and cleaning efficiency associated with each containment system were the criteria for comparing the effectiveness of the systems (large raceways, small raceways and washtub tanks). After 6 weeks, urchins maintained in large raceways displayed significantly higher mortality rates than urchins maintained in either the small raceways or washtub tanks (mean±SD: 24.3±10.4%, 8.0±3.5% and 4.3±1.5% respectively). Significant differences in cleaning time were detected among the three systems with washtub tanks requiring significantly more cleaning time (0.11±0.02 min urchin?1) than the other two systems and large raceways requiring significantly less cleaning time (0.06±0.02 min urchin?1) than the other two systems. No significant differences in gonad characteristics were detected among the three containment systems. Because of the higher mortality rate in the large raceways and the increased cleaning time required for the washtub tanks, the small raceways were considered to be the best of the three systems tested. 相似文献
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ABSTRACT: As a possible factor leading to the low recruitment level of sea urchins in kelp forests, the inhibitory effect of 2,4-dibromophenol (DBP) and 2,4,6-tribromophenol (TBP) released from the large perennial brown algae Ecklonia kurome and Eisenia bicyclis on survival and metamorphosis of eight-armed larvae of the sea urchin Strongylocentrotus nudus was examined. The percentage of larvae that underwent metamorphosis in filtered sea water after 1 h exposure to one-half dilution of saturated dibromomethane solution (∼60 ppm) as a chemical inducer reached approximately 100% after 1 h, while that in filtered sea water containing 1 ppm TBP was reduced to 73%. This was further reduced to less than 40% in the presence of 10 and 20 ppm TBP after 2 h. In filtered sea water containing 1 and 10 ppm DBP, the proportion of metamorphosed larvae was reduced markedly to 43 and 5% after 2 h, respectively. All larvae exposed to 50 ppm TBP and to 20 and 50 ppm DBP died after 1 h. These findings suggest that DBP is more toxic than TBP for sea urchin larvae, strongly inhibiting their metamorphosis. 相似文献
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强壮弧菌Vibrio fortis是虾夷马粪海胆Strongylocentrotus intermedius的一种致病菌.为建立强壮弧菌的PCR检测方法,根据强壮弧菌gyrB基因的高度变异区序列设计引物,筛选出特异性强的3对引物VF-6、VF-7及VF-8,分别对强壮弧菌S0907及20株参比菌株进行PCR扩增,结果显示,3对引物均对强壮弧菌扩增出与预期大小一致的目的基因片段且参考菌株无扩增条带.以不同稀释度的菌悬液制备的DNA模板进行PCR扩增,结果显示,3对引物VF-6、VF-7及VF-8可检测的最低细菌浓度分别为4.1×104、4.1×103、4.1 ×102cfu/mL;对不同稀释度的细菌DNA模板进行PCR扩增,结果显示,3对引物VF-6、VF-7及VF-8可检测的最低DNA含量分别为1.4、0.14、0.014 pg/μL.试验结果表明:3对引物的特异性均较好,但灵敏度存在差异,其中以VF-8为引物的PCR检测方法最佳;使用以VF-8为引物的PCR检测方法对实验室养殖海胆及其生境样品进行初步检测,健康海胆、养殖海水及投喂的海带均为阴性,而自然海域海水中带有一定量的强壮弧菌. 相似文献
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采用RT-PCR、PCR-SSCP等分子生物学技术和关联分析等方法对虾夷马粪海胆Strongylocentrotus intermedius CYP51基因的cDNA序列进行了克隆和单核苷酸多态性分析.结果表明:虾夷马粪海胆的CYP51基因包括一个1491 bp的开放阅读框,编码496个氨基酸;其开放阅读框的第161个核苷酸处存在1个单核苷酸多态性,即核苷酸发生了A→G突变.关联分析结果表明,该单核苷酸多态性与虾夷马粪海胆的体质量、性腺质量之间存在显著相关性(P<0.05).本研究中首次克隆了虾夷马粪海胆CYP51基因的cDNA序列并进行了SNPs分析,研究结果可为虾夷马粪海胆的分子标记辅助育种提供参考. 相似文献
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皱纹盘鲍与光棘球海胆越冬期筏式混养的初步研究 总被引:10,自引:3,他引:7
实验分越冬前期和越冬后期两个阶段进行。越冬前期鲍与海胆在生长方面的结果无显著差异,但混养可防止苔藓虫的附着,海胆的混养效果以20个/格略好;越冬后期海胆混养的密度则以5个-10个/格为最佳,混养可有效地防止多种敌害生物附着。 相似文献
17.
三种海胆性腺总脂的脂肪酸组成的研究 总被引:8,自引:1,他引:7
本文采用了FFAP石英毛细和气相色谱柱,对光棘球海胆,虾夷马粪海胆及海刺猬的性腺中总脂的脂肪酸组成进行了研究。结果表明这几种海胆含有四十种以上的脂肪酸,分布十分相似。主要的HUFA为18:4n-3(3.2%-7.4),20:4n-6(6.4%-16.7%)及20:5n-3(6.6%-12.1%),并含有非常罕见的n-5及n-7烯酸。 相似文献
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Measuring density effects on growth and survival of two size classes of juvenile sea urchins (Strongylocentrotus droebachiensis) held in sea‐based holding systems and impacts on holding system design and management 下载免费PDF全文
Assessing density in intensive sea urchin culture systems by measuring the percentage coverage of available surface area is an effective means of calculating the available space within a holding system, the proximity of the animals in the system to each other and the probable effects of the stocking density. The results of this study show that density plays a critical role in regard to both somatic growth (increase in test diameter measured in millimetres) as well as mortality of juvenile sea urchins ranging in size from 5 mm to 26 mm test diameter (the size range tested in the current experiments). These effects appear to be greater for smaller urchins. The critical percentage coverage densities are in the order of 50%‐60% coverage for juvenile sea urchins, and the authors advise farmers growing Strongylocentrotus droebachiensis to maintain stocking densities below this point and to reduce the stocking densities as and when stocks reach these critical density points. Percentage cover must be constantly monitored as the results from this study indicate that the growth rates of juvenile urchins can alter percentage coverage rapidly and reductions in density may be required as frequently as every 3‐4 months at the early juvenile stage. Holding system design should take these factors into account and incorporate a method of rapidly reducing stocking densities with minimal stress and handling of sea urchin stocks. 相似文献
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以初始体重为15.49±0.03 mg的方格星虫稚虫为实验对象,分别投喂以葡萄糖、蔗糖、糊精、木薯淀粉、土豆淀粉、玉米淀粉、糊化玉米淀粉作为饲料糖源的7种等氮(45%蛋白)等脂(9%脂肪)饲料56d,研究饲料中的糖源对稚星虫生长、成活率及体组成的影响.结果表明,糊化玉米淀粉组增重率和特定生长率最高,显著高于其他各糖源处理组(P<0.05),而饲料中糖源对稚星虫存活率没有显著影响(P>0.05).体组成分析的结果显示,不同糖源对稚星虫的体水分和体粗蛋白含量均有显著的影响(P<0.05),其中,葡萄糖处理组方格星虫稚虫的体水分含量最高,且显著高于土豆淀粉组(P<0.05),其他各实验组差异不显著;葡萄糖处理组方格星虫稚虫的体粗蛋白含量最低,显著低于糊化及非糊化淀粉组(P<0.05).不同糖源对稚星虫的体粗脂肪含量及灰分含量没有显著影响(P>0.05).在本实验条件下,稚星虫对大分子糖类(淀粉)的利用能力显著优于双糖(蔗糖)和单糖(葡萄糖).另外,玉米淀粉预糊化显著提高了方格星虫稚虫对玉米淀粉的利用. 相似文献