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1.
大弹涂鱼受精卵孵化技术   总被引:10,自引:3,他引:7  
在水温23.0-28.0℃,盐度20.8-23.5,PH8.0-8.1的条件下,大弹涂鱼受精卵经96h胚胎发育后开始孵出仔鱼,孵化时间延长至168h。人工授精卵在筛绢网上上的平均孵化率为4.2-20.5%;在塑料桶内的平均孵化率为36.3%-70.6%。  相似文献   

2.
双棘黄姑鱼人工育苗技术研究   总被引:4,自引:0,他引:4  
2002年5月,在集美大学水产学院水产试验场对双棘黄姑鱼人工育苗技术进行了研究。共135万粒受精卵,孵出68万尾仔鱼,孵化率50.3%.在育苗水温为25.4~29.4℃,海水盐度为26.6~30.6,饵料系列为轮虫一卤虫无节幼体一桡足类的条件下,经34d培养,育出全长14.5~24.3mm的双棘黄姑鱼幼鱼18万尾,育苗成活率达26.5%,确立了一套较完善的育苗生产工艺。  相似文献   

3.
本实验是应用鲤鱼♂和鲢鱼♀为材料,观察了杂交卵胚胎的发育过程和杂交鱼幼苗孵出后的变化,并做了杂交受精卵的石腊切片,用H.E染色,用光镜观察并照象。实验的结果如下: (1)实验证明鲤鱼♂和鲢鱼♀杂交卵的受精率,在三次观察中分别为74%,85%,86%,对照组受精率三次观察分别为73%,89.3%,90%。 (2)鲤♂×鲢♀杂交鱼的孵化率,二次观察计数分别为41%,51%。对照组(鲢♀×鲢♂)孵化率分别为60%,62%,74%,杂交种孵化的时间处于鲢和鲤鱼的中间类型。 (3)鲤鱼♂×鲢鱼♀杂交种鱼苗外部性状,在池塘喂养一个月后,尾鳍条是红的似鲤鱼性状,头部及躯体似鲢鱼,待鱼苗在池塘培育二个月后,完全似鲢鱼性状。 (4)鲤鱼♂×鲢鱼♀杂交后,鱼卵胚胎发育不规则。孵化出来的鱼苗有畸形,其形状为胸部膨大,尾部弯曲。  相似文献   

4.
采用人工催产、人工授精、去巢流水孵化等技术进行泥鳅人工繁殖技术初步研究。共计催产雌鳅67尾,获卵43.79万粒,平均催产率86.1%。平均受精率81.0%,平均孵化率78.4%,平均出苗率59.2%。另还描述了泥鳅胚胎发育主要阶段的观察结果。  相似文献   

5.
采用新的性腺发育控制技术和温控转换受精技术,对皱纹盘鲍与黑足鲍进行了杂交和自交育苗比较研究.结果表明,皱纹盘鲍♀×黑足鲍6的杂交受精率和孵化率分别为23.4%和32.87%,皱纹盘鲍自交受精率和孵化率分别为77.97%和76.86%,二者附着率和变态率相近;在水温20℃,盐度3.0%的条件下,杂交鲍胚胎发育速度明显比自交鲍滞后,但生长速度明显高于皱纹盘鲍,体现出较好的杂交优势.  相似文献   

6.
黄姑鱼♀与大黄鱼♂杂交试验与AFLP分析   总被引:1,自引:0,他引:1  
开展了黄姑鱼♀与大黄鱼♂杂交试验,并对杂交F1初孵仔鱼进行了AFLP分析.黄姑鱼♀与大黄鱼♂杂交能够正常受精,杂交受精率为93.54%,受精卵正常发育、孵化,孵化率为86.23%,但仔鱼在开口后一周内全部死亡.利用8对选择性扩增引物组合对亲本和杂交后代(家系)初孵仔鱼进行AFLP分析,共得到456个条带,其中母本特异条带(Female Special Band,FSB)178条、父本特异条带(Male Special Band,MSB)187条、双亲共有条带(Mutual Band,MuB)91条.且其中84条(47.2%)FSB、89条(47.6%)MSB和75条(82.4%)MuB为全部杂交仔鱼共有,其余94条(52.8%)FSB、98条(52.4%)MSB和16条(17.6%)MuB在杂交后代中发生了分离.分离的FSB和MSB中分别有33.0%和28.6%表现为偏分离.AFLP分析结果表明,黄姑鱼♀与大黄鱼♂杂交的初孵仔鱼含有双亲的条带,是真正的杂交种,是构建大黄鱼与黄姑鱼遗传图谱以及研究杂种在细胞和分子水平隔离机制的适合材料.  相似文献   

7.
温度对花尾胡椒鲷胚胎发育的影响   总被引:13,自引:1,他引:12  
研究了花尾胡椒鲷(Plectorhinchus cinctus)胚胎发育与孵化温度的关系,实验共设10个温度梯度组,实验结果表明:花尾胡椒鲷胚胎发育的适温范围为18-30度,最适温度范围为21-27度,在35度下,胚胎发育终止于尾芽期,而9-15度各组的胚胎发育终止于原肠期,24度试验组的孵化率最高,为96.5度,政党仔鱼孵出率也最高,为95.3%,在24度条件下孵化,初孵仔鱼平均全长最大(1.885mm),而卵黄囊体积最小,统计结果表明,孵化温度T与孵化时间H呈明显的曲线关系,相关方程为:H=0.0896T2-6.1123T+118.86,R2=0.9986,温度与积温S的相关方程则为:S=0.896T3-6.1123T2+118.86T。  相似文献   

8.
本文观察了25±10C条件下小菜蛾杂交品系与近亲交配品系的产卵规律及卵的孵化率。结果表明,两种饲养方式的小菜蛾在产卵总量、产卵前期、产卵期、雌成虫寿命等方面无明显差异,分别为83.1-239.3粒/雌、1.6-3.2 d、6.8-11.1 d、10.7-15.4 d。但近亲交配的小菜蛾到一定代数后出现卵的孵化率下降、雌成虫不产卵的个体,即不育个体增多的现象。在本文观察中,近亲交配的小菜蛾连续培养到第3代时,卵的孵化率为71.1%,显著低于杂交系的93.9%;第4代自交系的孵化率为60.1%,亦显著低于第4代杂交系的96.1%。第3、4代近亲交配品系的小菜蛾雌成虫不育率分别为9.0%、17.9%。  相似文献   

9.
日本黄姑鱼胚胎发育及温度对其过程的影响   总被引:2,自引:0,他引:2  
用Nikon显微镜观察了日本黄姑鱼胚胎发育全过程,并比较了受精卵在13种温度下胚胎的发育状况。结果表明:在水温为20~22.5℃、盐度29.9和pH 8.2条件下,从受精卵至孵化出膜总历时34 h 55 min,胚胎发育过程可划分为21期;孵化水温对受精卵的孵化率、畸形率和孵化时间有显著影响,孵化时数(h)、孵化积温(A)与平均水温(θ)密切相关,h=4265.9θ-1.547 9,A=3.420 1θ2-168.99θ+2 786.1;有效积温为480.04~553.96℃.h,阈温度为7.01℃,但实际孵化水温须高于12℃,14~28℃胚胎均能正常孵化。适宜孵化水温为17~22℃,孵化率高于89%,畸形率低于16%。  相似文献   

10.
白甲鱼(♀)与瓣结鱼(♂)杂交种的胚胎和胚后发育   总被引:4,自引:1,他引:3  
以白甲鱼为母本,瓣结鱼为父本进行人工杂交,在110~168℃自然水温条件下静水孵化,历时71小时30分孵化出膜.在138~232℃水温条件下,出膜30d后完成稚鱼发育,进入幼鱼发育阶段.经测定结果显示,受精率87%,胚胎畸形率67%,孵化率33%,出膜仔鱼畸形率20%.杂交种鱼既具有父本性状,又具有母本部分性状,证实绝非单性生殖.鱼巴亚科这两种不同属间鱼杂交表现出亲和性.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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