A comparative study of intensive Litopenaeus vannamei culture on four bottom substrates without water change     

Hongwei Shan  Li Zhang  Lei Gao  Yuepeng Su  Weiyang Bao  Shen Ma 《中国海洋大学学报(英文版)》2014,13(4):705-711

The effect of four bottom substrates, oyster shell powder (OP), sugarcane bagasse (SB), a mixture of OP and SB (OS) and fresh soil (FS), on the water quality and bacterial and zooplankton density of intensive shrimp (Litopenaeus vannamei) culture tanks without water change and the growth performance of cultured shrimp were compared in this study. At the end of a 110 days culturing trial, the total ammonium-N (TAN) of the water on SB and the nitrite nitrogen (NO₂-N) on OS was significantly lower than that on the other substrates (P<0.05), which coincided with the high density of ammonium- and nitrite-oxidizing bacteria in the water on SB and OS, respectively. The concentration of chlorophyll a (Chl a) increased slowly on OP, SB and OS but remained low on FS. The density of total bacteria on OP, SB and OS was one order of magnitude higher than that on FS, and the density of zooplankton on SB and OS was significantly higher than that on FS or OP (P<0.05). The improved water quality and increased density of bacteria and zooplankton on SB and OS may have had a synergistic effect on shrimp culture, improving its growth performance (high survival rate and yield and low feed conversion rate). SB and OS were more effective for improving the growth performance of intensively cultured L. vannamei without water change than OP and FS. To our knowledge, this study presents the first evidence regarding the effect of different bottom substrates on intensive shrimp culture.  相似文献   

Multi-technique approach to characterise the effects of cryopreservation on larval development of the Pacific oyster (Crassostrea gigas)     

S Suneja  AB Rusk  JR Morrish  HR Tervit  LT McGowan 《新西兰海洋与淡水研究杂志》2014,48(3):335-349

Cryopreservation experiments were conducted on D-stage larvae of the Pacific oyster (Crassostrea gigas) to investigate the effects of two cryoprotectant solutions and three cooling rates on larval development from 1 to 22 days post-fertilisation. Cryoprotectant solutions were made up to final concentrations (after 1:1 dilution with larvae) of 10% ethylene glycol, 1% polyvinylpyrrolidone and either 0.2 or 0.4 M trehalose. Three cooling rates (0.5, 1 and 2 °C min^?1 between ?10 and ?35 °C post-holding) were tested in an orthogonal design with the two cryoprotectants. Results indicate that control larvae out-performed all cryopreservation treatments for survival, feeding consumption and shell length parameters. However, larvae exposed to 0.4 M trehalose did considerably better than those exposed to 0.2 M trehalose, regardless of cooling rate conditions. Scanning electron and light microscopy observations were used to assess larval morphology and organogenesis, indicating that treatments with surviving larvae were morphologically and developmentally similar to control larvae.  相似文献   

Genome-wide survey and analysis of microsatellites in the Pacific oyster genome: abundance,distribution, and potential for marker development     

王家丰  亓海刚  李莉  张国范 《中国海洋湖沼学报》2014,32(1):8-21

Microsatellites are a ubiquitous component of the eukaryote genome and constitute one of the most popular sources of molecular markers for genetic studies. However, no data are currently available regarding microsatellites across the entire genome in oysters, despite their importance to the aquaculture industry. We present the fi rst genome-wide investigation of microsatellites in the Pacifi c oyster Crassostrea gigas by analysis of the complete genome, resequencing, and expression data. The Pacifi c oyster genome is rich in microsatellites. A total of 604 653 repeats were identifi ed, in average of one locus per 815 base pairs(bp). A total of 12 836 genes had coding repeats, and 7 332 were expressed normally, including genes with a wide range of molecular functions. Compared with 20 different species of animals, microsatellites in the oyster genome typically exhibited 1) an intermediate overall frequency; 2) relatively uniform contents of(A)n and(C)n repeats and abundant long(C)n repeats(≥24 bp); 3) large average length of(AG)n repeats; and 4) scarcity of trinucleotide repeats. The microsatellite-fl anking regions exhibited a high degree of polymorphism with a heterozygosity rate of around 2.0%, but there was no correlation between heterozygosity and microsatellite abundance. A total of 19 462 polymorphic microsatellites were discovered, and dinucleotide repeats were the most active, with over 26% of loci found to harbor allelic variations. In all, 7 451 loci with high potential for marker development were identifi ed. Better knowledge of the microsatellites in the oyster genome will provide information for the future design of a wide range of molecular markers and contribute to further advancements in the fi eld of oyster genetics, particularly for molecular-based selection and breeding.  相似文献   

牡蛎不同组织细胞核DNA含量比较   总被引：7，自引：3，他引：4  

郑晓东  王昭萍  张筱兰  张海滨  王如才 《中国海洋大学学报(自然科学版)》1999,(3)

以太平洋牡蛎新鲜的鳃、闭壳肌及性腺组织为试材,利用流式细胞计分别测定三个组织细胞核ＤＮＡ的含量。其中,鳃及闭壳肌组织细胞核ＤＮＡ相对含量在个体间及组织之间比较恒定,而性腺组织细胞核ＤＮＡ含量受温度影响比较大,个体间差异明显,且与鳃及闭壳肌组织细胞核ＤＮＡ含量均呈明显差异。结果说明,鳃及闭壳肌组织是测定牡蛎细胞核ＤＮＡ含量用于倍性鉴定的理想试材。  相似文献   

单体“海大1号”长牡蛎苗种室内人工培育模式的优化     

张哲  于瑞海  李海昆  马培振  李玲蔚  王永旺 《中国海洋大学学报(自然科学版)》2021,(2)

为提高单体“海大1号”长牡蛎(Crassostrea gigas)的培育效率,本研究以3种培育模式(下降流、上升流和静水)、6个水流量梯度(20、35、50、65、80和95 mL/s)和6个培育密度梯度(2.5、5、7.5、10、12.5和15个/mL)对单体“海大1号”长牡蛎苗种中间培育生长情况进行了研究。研究表明,单体“海大1号”长牡蛎苗种中间培育时,上升流和下降流均比静水培育效果好,培育前5天采用下降流、第6~29天采用上升流时,稚贝生长快、死亡率低;水流量小于65 mL/s时,随水流量的增加,稚贝生长加快,死亡率降低,水流量在65~80 mL/s时,单体牡蛎稚贝生长存活最优,第29天时最大壳高达(1534.81±65.23)μm。单体“海大1号”长牡蛎稚贝苗种中间培育时,随着培育密度的增大,挤迫效应逐渐显现,密度为7.5个/mL时,死亡率相对较低,且稚贝生长速度快,在第29天时稚贝壳高最大可达(1520.63±51.72)μm。基于以上研究结果,建议在规模化单体“海大1号”长牡蛎稚贝中间培育时,采用上升流和下降流相结合的流水培育方式,适当增加水流量,及时疏散密度。本研究优化了单体“海大1号”长牡蛎室内培育模式,为单体牡蛎规模化培育提供了参考方法和理论依据。  相似文献   

渤海湾西部浅海区活牡蛎礁调查结果及资源保护建议     

范昌福  裴艳东  田立柱 《地质通报》2010,29(5):660-667

采用旁侧声呐、浅地层剖面仪和单波束水深测量多种物探仪器联机,同步调查天津大神堂浅海区的水下活牡蛎礁资源,为合理保护活牡蛎礁资源提供科学依据。调查结果表明,该区活牡蛎资源由3个分散礁体组成,总面积仅约3km2,礁体最大厚度1.2m,平均厚度0.6m;调查区海底地形平坦,水深介于3.4~5.6m之间,因受人类活动严重破坏,仅在有礁体发育的局部范围内有高程约1m的起伏波动。为了生态资源的完整,必须对现存的活牡蛎礁体进行保护和恢复。  相似文献   

渤海湾西北岸埋藏牡蛎礁礁顶上下沉积物中硅藻对“礁泥转换”古沉积环境的重建     

方晶  王宏  王福  商志文  胡克  杨永强  范昌福  王海峰 《沉积学报》2012,30(5):879-890

渤海湾西北岸大吴庄牡蛎礁是近年来研究程度最高的礁体,天津空港物流中心牡蛎礁则是近年来新发现的礁体。该两处礁体上部的牡蛎个体内部充填的泥、个体之间的泥以及礁体上覆沉积泥层中的硅藻研究表明,礁顶上下（即礁体的上部-顶部和上覆沉积泥层的下部）均富含潮间带环境指示种的Auliscus caelatus,表明礁体发育后期和上覆沉积泥层的初期,均为潮间带环境。尽管如此,从礁顶向上覆沉积泥层转换方式在两处礁体却不相同:（1）大吴庄:Auliscus caelatus种向上逐渐减少,暗示着大吴庄剖面由礁体上部的潮间带中上部、直至上覆沉积泥层下部的潮间带上部、进一步向上覆沉积泥层上部的潮上带转化的趋势。（2）空港:牡蛎礁上覆沉积泥层出现了比例达6%~23%的河口咸水-半咸水种Achnanches brevipes,而下伏礁体内则未见该种,暗示此处泥层受河口作用显著影响。此种不同揭示了礁体停止发育的原因有所不同:在5 520cal BP时,大吴庄礁顶进入潮间带中上部,礁体经常脱离海水而发育停止;在约4 000 cal BP时,空港礁体所在位置因河流作用突然增强,在时间上看很可能是黄河改道在天津入海,古黄河携带大量泥砂入海,掩盖了潮间带的牡蛎礁而导致牡蛎礁发育停止。  相似文献   

渤海湾西北岸牡蛎礁体对区域性构造活动与水动型海面变化的响应   总被引：9，自引：2，他引：7       下载免费PDF全文

范昌福  王宏  李建芬  裴艳东  王福  商志文 《第四纪研究》2005,25(2):235-244

渤海湾地区广泛分布的古海面标志物,为建立该地区的相对海面变化曲线提供了良好的基础。过去20年来该地区已相继建立了一些相对海面变化曲线,但在讨论影响古海面标志物高程的因素时,未将构造活动与水动型海面变化及均衡作用对高程的贡献量加以区分。文章以该地区7个点的古海面标志物及相关层位的高程测量与年代学测定结果,经与地区性预测海面变化曲线进行对比后,定量讨论了该地区海面变化(包括绝对海面变化与冰川、水均衡作用)与构造活动对古海面标志物高程的贡献;并以壳体的稳定同位素、地层记录与古地震研究资料讨论了牡蛎礁体在建礁过程中所记录的构造下沉。  相似文献   

Feasibility of co-culture of the Australasian sea cucumber (Australostichopus mollis) with the Pacific oyster (Crassostrea gigas) in northern New Zealand     

LN Zamora  J Dollimore  AG Jeffs 《新西兰海洋与淡水研究杂志》2014,48(3):394-404

The Australasian sea cucumber (Australostichopus mollis) has attracted commercial attention for aquaculture development, partly due to its potential for co-culture with shellfish and finfish species. However, minimal attention has been given to the possibility of co-culturing this species with oysters. In this study we evaluated the growth of juvenile sea cucumbers (36.7 ± 0.9 g, wet weight) caged underneath Pacific oyster farms in northern New Zealand. Co-culture started at the end of the summer, and after 304 days the juveniles had doubled in size (79.8 ± 3.3 g, wet weight), but their subsequent growth appeared to be constrained by overstocking of the cages and summer water temperatures, reaching a carrying capacity of 720 g m^?2. Overall, the results of this study indicate that the co-culture of juvenile sea cucumbers with Pacific oysters is feasible, if sea cucumber losses are reduced (between 33% and 52% lost in this study) and careful attention is given to stocking rates and the water temperature regimes of oyster farms in order to maintain adequate growth rates.  相似文献   

马氏珠母贝早春育苗,缩短母贝养成期试验     

陈兆和  周庆堂  何水养  王忠 《广东海洋大学学报》1989,(Z1)

在室内人工飼养马氏珠母贝亲贝,进行早春育苗。比常规生产育苗提前二个月。生长快,贝体健壮,经养殖18个月长至壳高7.1厘米,体重52克。60％以上达施术贝标准,相当于常规生产贝苗26个月的生长水平。相对地缩短了养殖周期,提高了经济效益。且设备简单,操作方便,利于推广。  相似文献