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1.
作者以初体质量为(4.80±0.11)g的大菱鲆(Scophthalmus maximus)为研究对象,在循环水水族箱中进行60 d饲喂实验,研究饲料中添加单一益生菌和复合益生菌对大菱鲆肠道菌群及部分血液免疫指标的影响。以基础饲料为对照组,在基础饲料中分别添加枯草芽孢杆菌(Bacillus subtilis)、地衣芽孢杆菌(Bacillus licheniformis)、枯草芽孢杆菌+地衣芽孢杆菌(1:1)、嗜酸乳酸菌(Lactobacillus acidophi-lus)、双歧杆菌(Bifidobacterium inopinatum)、嗜酸乳酸菌+双歧杆菌(1:1)、枯草芽孢杆菌+地衣芽孢杆菌+嗜酸乳酸菌+双歧杆菌(1:1:1:1),每克饲料约含菌3.0×109个/g干质量,共配制7种实验饲料。实验结果显示,饲料中添加益生菌对肠道中总菌数无显著影响,但显著降低了肠道弧菌数(P<0.05),显著提高了大菱鲆酚氧化酶活力、溶菌酶活性和总抗氧化力。添加不同的益生菌对血细胞数、血清蛋白浓度及超氧化物歧化酶的影响不同,例如添加的益生菌中含有乳酸菌能显著提高大菱鲆血清蛋白浓度(P<0.05),而添加芽孢杆菌无此效果。上述实验结果表明,与添加单一益生菌相比,在饲料中添加复合益生菌对降低大菱鲆肠道弧菌总数,提高机体免疫力具有更好的促进作用。  相似文献   

2.
《海洋科学》2012,36(2)
作者以初体质量为(4.80±0.11)g的大菱鲆(Scophthalmus maximus)为研究对象,在循环水水族箱中进行60 d饲喂实验,研究饲料中添加单一益生菌和复合益生菌对大菱鲆肠道菌群及部分血液免疫指标的影响。以基础饲料为对照组,在基础饲料中分别添加枯草芽孢杆菌(Bacillus subtilis)、地衣芽孢杆菌(Bacillus licheniformis)、枯草芽孢杆菌+地衣芽孢杆菌(1:1)、嗜酸乳酸菌(Lactobacillus acidophi-lus)、双歧杆菌(Bifidobacterium inopinatum)、嗜酸乳酸菌+双歧杆菌(1:1)、枯草芽孢杆菌+地衣芽孢杆菌+嗜酸乳酸菌+双歧杆菌(1:1:1:1),每克饲料约含菌3.0×109个/g干质量,共配制7种实验饲料。实验结果显示,饲料中添加益生菌对肠道中总菌数无显著影响,但显著降低了肠道弧菌数(P〈0.05),显著提高了大菱鲆酚氧化酶活力、溶菌酶活性和总抗氧化力。添加不同的益生菌对血细胞数、血清蛋白浓度及超氧化物歧化酶的影响不同,例如添加的益生菌中含有乳酸菌能显著提高大菱鲆血清蛋白浓度(P〈0.05),而添加芽孢杆菌无此效果。上述实验结果表明,与添加单一益生菌相比,在饲料中添加复合益生菌对降低大菱鲆肠道弧菌总数,提高机体免疫力具有更好的促进作用。  相似文献   

3.
研究了地衣芽孢杆菌(Bacillus licheniformis)对尖吻鲈(Lates calcarifer)的生长及消化酶活性的影响.地衣芽孢杆菌制剂(含量为10×108cfu/g)分别以0.0%(对照组)、0.1%、0.2%、0.3%、0.4%、0.5%和0.6%的比例添加到饲料中,投喂初始体重为17.47±0.19 g的尖吻鲈,养殖时间8周.随着地衣芽孢杆菌添加量的增加,尖吻鲈的增重率和特定生长率逐渐增高,在0.5%组达到最大,增重率提高9.77%,特定生长率提高4.56%;同时该组的肥满度也显著高于对照组(p〈0.05).尖吻鲈的增重率、特定生长率、饲料系数、存活率、脏体比和肝体比在各组间都没有显著差异(p〉0.05).尖吻鲈的前肠蛋白酶在0.2%组达到最大,并显著高于对照组(p〈0.05),其他组别及部位的消化酶则低于对照组或差异不显著.结果表明,地衣芽孢杆菌对尖吻鲈的生长有一定促进作用,但此作用与消化酶变化相关不明显.  相似文献   

4.
试验以半透膜法收集地衣芽孢杆菌(Bacillus licheniformis)De株的胞外产物(extracellular products,ECP),以匀浆离心法提取凡纳滨对虾(Litopenaeus vannamei)成虾的肝胰腺和肠道消化酶,将芽孢杆菌胞外产物和对虾消化酶按体积比10∶90混合,采用体外分析法研究在不同温度、pH及胞外产物添加量等条件下胞外产物对对虾淀粉酶活性的影响.试验共设A、B、C、D、E 5个试验组,每组三个平行.其中空白组A为地衣芽孢杆菌的胞外产物,试验组B、C组分别为添加了胞外产物的对虾肝胰腺消化酶、肠道消化酶,对照组D、E分别为未添加胞外产物的对虾肝胰腺消化酶和肠道消化酶样品.温度为20~40℃时试验组B、C的淀粉酶活性要明显高于对照组(p<0.05),其中肝胰腺淀粉酶和肠道淀粉酶的活性分别提高了25.9%和19.3%,但该温度要远低于芽孢杆菌胞外淀粉酶的最适温度60~90℃.在pH为5~6时,试验组B、C的淀粉酶活性明显高于对照组(p<0.05),对虾肝胰腺淀粉酶和肠道淀粉酶的活性分别较对照组提高了33.3%和122.2%,而该pH同样要低于芽孢杆菌胞外淀粉酶的最适pH值(6~9).此外,研究还表明试验组的淀粉酶活性随胞外产物添加量的升高而降低,即胞外产物在一定条件下可能抑制对虾内源淀粉酶的生物学活性.从本研究看,地衣芽孢杆菌胞外产物在一定程度上可促进对虾的淀粉酶活性,而当胞外产物活性高于0.02 U/mg蛋白质时,对虾淀粉酶活性将受到抑制.  相似文献   

5.
研究了泼洒蜡样芽孢杆菌(Bacillus cereus)BC-01对刺参(Apostichopus japonicus)生长的影响,并应用PCR-DGGE技术分析了养殖水体和肠道细菌群落结构的变化。芽孢杆菌的泼洒浓度分别为106、108和1010cfu/m3(分别命名为BC6、BC8和BC10),每7d全量换水1次,以未泼洒芽孢杆菌处理为对照组2(CT2)。另外设置每隔3d全量换水1次的未泼洒芽孢杆菌处理作为对照组1(CT1)。8周的养殖实验表明,BC6处理组刺参的末体重显著高于2个对照组(P0.05),BC8和BC10处理组刺参的末体重显著高于对照组CT1(P0.05)。而BC6和BC8处理组的刺参特定生长率均显著高于CT1和CT2处理组(P0.05)。研究发现,刺参养殖水体中的优势菌群归属于α-变形菌纲(α-Proteobacteria)、γ-变形菌纲(γ-Proteobacteria)、δ-变形菌纲(δ-Proteobacteria)、黄杆菌纲(Flavobacteria)、拟杆菌纲(Bacteroidetes)和疣微菌纲(Verrucomicrobiae),各处理水体中细菌群落结构明显不同,蜡样芽孢杆菌未能在养殖水体中形成优势菌群。刺参肠道内含物中优势菌群归属于α-变形菌纲、γ-变形菌纲、ε-变形菌纲、黄杆菌纲、拟杆菌纲和芽孢杆菌纲,以BC8和BC10处理组之间的相似度最高。芽孢杆菌纲(Bacilli)细菌在3个处理组刺参肠道内含物中成为优势菌群,并在BC6处理组成为第一优势菌群,而相对于CT2对照组,拟杆菌纲细菌相对丰度在3个处理组中显著下降。刺参肠道固定菌群的优势菌群归属于α-变形菌纲、γ-变形菌纲、黄杆菌纲和芽孢杆菌纲,相对于对照组CT1和CT2,3个处理组刺参肠道γ-变形菌纲的相对含量明显下降。相对于对照CT2,BC6和BC8处理组中芽孢杆菌成为第一优势菌群。黄杆菌纲细菌比例随芽孢杆菌添加量的增加而升高。本研究表明,水体中泼洒该芽孢杆菌制剂对水体和刺参肠道菌群结构均具有显著影响,在适宜的泼洒浓度下可以有效提高刺参的生长速度。  相似文献   

6.
本研究比较了饲料中添加粪肠球菌(Enterococcus faecalis LYB1)、嗜酸乳杆菌(Lactobacillus acidophilus W2)和凝结芽孢杆菌(Bacillus coagulans NJ17)对凡纳滨对虾(Litopenaeus vannamei)幼虾的生长、抗病力及肠道菌群结构的影响。以基础饲料中分别添加1.0×1010 cfu/kg浓度的3种不同乳酸菌为实验组,以基础饲料为对照组,以投喂方式养殖对虾42 d。养殖结束后,进行14 d的副溶血弧菌(Vibrio parahaemolyticus)攻毒实验。研究表明:投喂3种乳酸菌的实验组对虾的体重、特定生长率、饲料效率和表观消化率均显著高于对照组(P<0.05),其中以添加凝结芽孢杆菌组效果最佳。攻毒实验显示,添加粪肠球菌和嗜酸乳杆菌均可显著降低对虾的累计死亡率(P<0.05)。添加乳酸菌的各实验组对虾的肠道细菌群落结构与对照组相比均发生了明显变化,其中以添加粪肠球菌组差异最大。在门水平上,变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidetes)为对虾肠道优势菌群。在纲分类水平上,α-变形菌纲(Alphaproteobacteria)、丹毒丝菌纲(Erysipelotrichia)和黄杆菌纲(Flavobacteriia)为对虾肠道优势菌群。研究结果显示,凝结芽孢杆菌NJ17对凡纳滨对虾促长效果最佳,而嗜酸乳杆菌W2对对虾抗病力提高效果最佳,3种乳酸菌均明显改善了对虾肠道微生物群落的组成和丰度。  相似文献   

7.
本文研究了不同饲料添加物对凡纳滨对虾(Litopenaeus vannamei)肠道菌群结构的影响。实验设计了5种不同的饲料添加物,分别为破壁酵母(A,添加量为0.6%)、中草药提取物(B,添加量为0.3%)、柠檬酸(C,添加量为0.3%)、益生菌(D,蜡样芽孢杆菌Bacillus cereus BC-01,添加量为109cfu/kg)和氟苯尼考(E,添加量为15mg/kg),以投喂实验用基础饲料组作为对照(F)。每个处理组分别设置了5个重复,每个重复10尾虾,实验进行了42d。采用PCR-DGGE技术分析了饲料中不同添加物对凡纳滨对虾肠道菌群结构的影响,研究结果表明:凡纳滨对虾肠道内菌群归属于γ-变形菌纲、黄杆菌纲和芽孢杆菌纲,它们分别为埃希氏菌属(Escherichia)、弧菌属(Vibrio)、假交替单胞菌属(Pseudoalteromonas)、芽孢杆菌属(Bacillus)、志贺氏菌属(Shigella)、Tamlana属和Formosa属。A、B、C和D处理组以埃希氏菌属为主要优势菌,E组和对照组以弧菌属为主要优势菌。其中,对照组中弧菌的相对含量最高为37.74%,其次是E组,相对含量为23.79%。总体比较,添加中草药提取物、柠檬酸及芽孢杆菌处理组对虾肠道菌群结构相似,而与添加破壁酵母、氟苯尼考和对照组的细菌群落结构有所差异。饲料中添加适量的破壁酵母、中草药提取物、柠檬酸、芽孢杆菌及氟苯尼考均对凡纳滨对虾肠道内的弧菌属细菌有一定的抑制作用,其中以添加0.6%的破壁酵母效果最佳,可有效抑制对虾肠道中的弧菌属细菌。  相似文献   

8.
几种益生菌对大菱鲆幼鱼生长及消化酶活性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
作者以初体质量为(4.80±0.11)g 的大菱鲆(Scophthalmus maximus)为研究对象,在循环水水族箱中进行60 d 饲喂实验,研究饵料中添加单一益生菌和复合益生菌对大菱鲆生长及消化道酶活性的影响.以基础饲料为对照组,在基础饲料中分别添加枯草芽孢杆菌(Bacillus subtilis)、地衣芽孢杆菌...  相似文献   

9.
选取初始体重(3.58±0.32)g的凡纳滨对虾,在饲料中分别添加溶藻弧菌(Vibrio alginolyticus)活菌、溶藻弧菌破碎菌、芽孢杆菌(Bacillus sp.)活菌和芽孢杆菌破碎菌和使其菌含量为108 CFU/g,通过49d的养殖实验研究饲料中添加芽孢杆菌和溶藻弧菌对凡纳滨对虾的消化酶、免疫相关酶和抗病力的影响。结果显示:(1)4个处理组对虾的肠道蛋白酶水平均显著提高。25d时各处理组淀粉酶水平均显著高于对照组,49d时弧菌破碎组和杆菌破碎组对虾的淀粉酶水平高于对照组(P0.05),其中杆菌破碎组对虾肠道的消化酶水平最高,杆菌组对虾肠道消化酶水平低于其他处理组。(2)49d时弧菌组对虾的超氧化物歧化酶(SOD)水平上升(P0.05);弧菌破碎组对虾的SOD、酚氧化酶(PO)和抗菌酶水平上升(P0.05);杆菌组对虾PO水平上升,抗菌酶水平下降(P0.05);杆菌破碎组对虾SOD和PO水平均上升,抗菌酶水平下降(P0.05)。(3)WSSV攻毒的半致死时间为杆菌破碎组弧菌破碎组弧菌组杆菌组对照组。研究表明,饲料中添加芽孢杆菌和溶藻弧菌及其破碎菌体均能在一定程度上提高对虾的消化酶活力和抗病力。其中添加弧菌破碎菌体能更好的提高对虾的免疫酶水平,添加杆菌破碎菌体能促进对虾消化和抗病力。  相似文献   

10.
旨在探究养殖水体中添加球形赖氨酸芽孢杆菌对斑马鱼幼鱼生长、抗氧化免疫、肠道菌群与代谢的影响。将初体重为(0.019±0.003) g的270尾斑马鱼随机均分为3组, ZF0组(对照组, 基础饲料)、ZF5组(基础饲料+105CFU/mL球形赖氨酸芽孢杆菌)与ZF7组(基础饲料+107CFU/mL球形赖氨酸芽孢杆菌), 每组3个平行,试验周期为33 d。实验结果表明: (1) 各组间的终末体重、增重率和特定生长率都没有显著性差异(P>0.05)。(2) ZF5和ZF7组的GPT活性显著高于ZF0组(P<0.05), ZF5组AKP的活性显著高于其他组(P<0.05)。(3) ZF7组胰蛋白酶和脂肪酶的活性相对于ZF0和ZF5组显著提高(P<0.05)。(4) ZF7组肠道绒毛高度、V/C都显著高于ZF0与ZF5组(P<0.05); ZF7组的隐窝深度显著低于其他两组(P<0.05)。(5) 从肠道菌群组成来看, 各组间优势菌门均为变形菌门(Proteobacteria), ZF5和ZF7组显著降低了肠道中梭杆菌门(Fusobacteriota)的丰度并显著提高了放线菌门(Actinobacteriota)的丰度(P<0.05)。属水平上, 对照组与试验组的优势菌属为鲸杆菌属(Cetobacterium), 试验组显著减少了邻单胞菌属(Plesiomonas)的丰度同时显著提高了戈登氏菌属(Gordonia)、细杆菌属(Microbacterium)等有益菌属的丰度(P<0.05)。(6)ZF5和ZF7组与ZF0组的肠道代谢物差异明显, 其中Lipoxin a4、Prostaglandin g2和11-dehydrothromboxane b2显著上调(P<0.05), 5''-phosphoribosyl- 5-amino-4-imidazolecarboxamide (aicar)显著下调(P<0.05)。差异代谢物主要富集在ABC转运蛋白、神经活性配体-受体相互作用以及丙氨酸、天冬氨酸和谷氨酸通路中。综上所述,养殖水体中添加球形赖氨酸芽孢杆菌有利于改善斑马鱼幼鱼的肠道消化性能、组织结构和微生物多样性及其代谢产物。  相似文献   

11.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

12.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   

13.
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.  相似文献   

14.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

15.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.  相似文献   

16.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

17.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

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《海洋学报(英文版)》2014,(11):161-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

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