黄海中部小黄鱼摄食习性的体长变化与昼夜变化

根据2001年3月至2002年1月在黄海中部海域进行的4个季节的定点底拖网调查,应用聚类分析、单因素方差分析和列联表检验等方法,对小黄鱼(PseudosciaenapolyactisBleeker)摄食的体长和昼夜变化进行研究。结果表明:摄食强度没有明显的体长变化,而食物组成却有明显的体长变化。随着体长的增大,鱼类和虾类的比例有所增加,而磷虾类、桡足类和端足类的比例则减少。饵料生境宽度在体长大于109mm后有明显的增加。经检验,小黄鱼平均每个胃中含有的饵料个数显著减少而饵料重量则增加,这符合"最佳摄食理论"。聚类分析的结果表明,小黄鱼在体长达到109mm时,出现了明显的食物转换现象。小黄鱼的摄食强度在各个季节都有明显的昼夜变化,午夜24:00和早晨08:00是2个摄食高峰期。     

用逆转录多聚酶链式反应从凡纳对虾中检出传染性皮下组织和造血器官坏死病毒

传染性皮下组织和造血器官坏死病毒 (ＩＨＨＮＶ) ,是一种细小病毒 ,它能感染所有起源于中胚层和外胚层的对虾组织细胞[1] 。在许多养殖对虾的国家都有ＩＨＨＮＶ ,特别是中美洲国家和地区[2 ] 的对虾养殖业深受其害。随着各国间对虾贸易的急剧增长 ,ＩＨＨＮＶ地理分布范围日益广泛 ,迄今为止 ,已扩散到中国台湾、新加坡、马来西亚、泰国、印度尼西亚、澳大利亚、菲律宾、厄瓜多尔、秘鲁等国家和地区[2 -4] 。红额角对虾 (Ｐｅｎａｅｕｓｓｔｙｌｉｒｏｓｔｒｉｓ)、斑节对虾 (Ｐ .ｍｏｎｏｄｏｎ)、短沟对虾 (Ｐ .ｓｅｍｉｓｕｌｃａｔｕ…     

Virus infections of the European Eel in North Rhine Westphalian rivers

Viral infections have been suggested to play a role in the decline of the panmictic population of the European eel (Anguilla anguilla). However, despite the importance of knowledge about pathogenic eel viruses, little is known about their spread in the wild European eel population and only a few eel pathogenic viruses have been described so far. In this study, we aimed to investigate the health status of the A. anguilla stock in North Rhine Westphalia (NRW) State of Germany. For this purpose, we examined tissue samples of 16 elvers, 100 yellow eels and 6 silver eels, sampled from the rivers Rhine, Lippe and Ems. Virus detection was performed via a combination of cell culture and PCR. Next to the detection of frequently encountered pathogenic eel viruses (anguillid herpesvirus 1 and eel virus European X (EVEX)), we isolated the eel picornavirus 1 (EPV-1) from tissue of yellow eels and elvers and demonstrate the distribution of EPV-1 in wild eel population in NRW.     

Detection of antigenic proteins expressed by lymphocystis virus as vaccine candidates in olive flounder, Paralichthys olivaceus (Temminck & Schlegel)

Although the major capsid proteins (MCPs) of lymphocystis disease virus (LCDV) have been characterized, little is known about the host-derived immune response to MCPs and other LCDV antigenic proteins. To identify antigenic proteins of LCDV that could be used as vaccine candidates in olive flounder, Paralichthys olivaceus, we analysed the viral proteins responsible for its virulence by applying immuno-proteomics. LCDV proteins were separated by one-dimensional gel electrophoresis, transferred to polyvinylidene difluoride membrane, and probed with homogeneous P. olivaceus antisera elicited by LCDV natural infection and vaccination with formalin-killed LCDV. Four immune-reactive proteins were obtained at 68-, 51-, 41- and 21 kDa using antisera collected from natural infection while two proteins at 51- and 21 kDa exhibited response to antisera from vaccinated fish, indicating that the latter two proteins have vaccine potential. Using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and nanoelectrospray MS/MS, the 51 and 21 kDa proteins were identified as MCP and an unknown protein, respectively.     

Gill-associated virus and its association with decreased production of Penaeus monodon in Australian prawn farms

Gill‐associated virus (GAV) was found to be associated with decreased prawn, Penaeus monodon, production when prawns from three farms (n = 45 ponds, 1800 prawns) were monitored for GAV over the production season using a graded RT‐nPCR. The grading system used was a visualization of either the outer or inner nested PCR products. Prevalence and loading of GAV were associated with disease severity. Ponds with a higher initial prevalence and a larger increase in GAV load over the production period suffered disease outbreaks. Ponds with low initial prevalence of GAV but a larger increase in prevalence and large increase in load over the production period suffered chronic disease with no disease outbreak identified, yet low production. However, the ponds with moderate to low initial prevalence of GAV with a low increase in prevalence and load of GAV over the production period incurred no disease outbreak and comparatively high production. Ponds with GAV prevalence greater than 75% at 1 month post‐stocking should be considered for termination as they have a high probability (95%) of having a disease outbreak. Emergency harvest when a disease outbreak occurs will significantly limit mortality losses.     

近10 a黄河三角洲LUCC及其驱动因素分析

研究滨海脆弱生态区的土地利用/土地覆被时空变化过程,可以为区域土地资源的规划、开发和管理提供科学依据。该文应用遥感和GIS技术,分析黄河三角洲区域1995－2004年间土地利用/土地覆被的时空变化特征,并对区域土地利用/土地覆被变化的驱动因子进行了探讨。结果表明,近10 a来黄河三角洲的土地利用/土地覆被类型发生了复杂变化;黄河三角洲土地利用/土地覆被动态受到自然因素和人类活动的共同作用,而人类活动是近10 a区域土地利用/土地覆被变化的主要驱动因子。尽管近年来黄河三角洲的开发取得了快速发展,但部分人类经济活动给区域土地资源及其生态环境的可持续发展带来巨大压力,甚至导致区域土地质量的进一步退化。     

不同含盐土壤圆盘入渗特征试验

不同含盐土壤水分入渗特征是获得准确的土壤水力参数的基础。该文通过圆盘入渗试验,分析了4种土壤在5个（-1、-3、-6、-9和-12 cm）负水头下的入渗特征。结果表明,随着水头的减小,4种土壤的吸湿率线性减小,稳定入渗率和非饱和导水率呈不同程度减小。随土壤含盐量增加稳定入渗率和导水率呈增大规律。根据实测资料确定了不同负水头下非饱和导水率的Gardner指数模型参数,为盐渍化土壤水力参数的确定提供理论参考。     

黄河三角洲农业用地动态变化模拟与情景分析

为明确农业用地变化的动态特征和影响要素,预测不同情景下的农业用地的时空变化格局。利用遥感和地理信息系统技术对黄河三角洲地区4期TM和ETM+影像进行解译判读,获取区域内1992－2005年间农业用地动态演化特征,并构建元胞自动机模型对2001年和2005年的农业用地格局进行模拟。2001年和2005年农业用地模拟的总体精度分别为82.90%和84.48%,Kappa系数分别为0.658和0.689。模拟结果表明元胞自动机模型能够较好地模拟研究区域内农业用地动态变化,为农业用地的演变模拟提供了一种适用的工具。利用元胞自动机模型对4种情景下（面积减少5%、增加5%、10%和15%）的农业用地演变进行了预测。情景分析表明刁口故道附近的农业用地并不稳定,容易发生变化,是需要重点关注的区域。     

多重实时RT-PCR快速检测新型甲型H1N1流感病毒

从GenBank中获取新型甲型H1N1流感病毒(2009年流行株)HA和NA基因序列,通过多重序列比对之后,设计合成H1和N1基因特异性的引物和探针,用来建立新的甲型H1N1亚型流感病毒的多重实时RT-PCR检测方法.合成的两条荧光探针分别标记FAM和CY5荧光报告基团,荧光淬灭均使用BHQ基团.多重实时RT-PCR实验在ABl7500实时PCR仪上进行,经过40个循环的扩增之后,阳性对照出现标准的S型曲线,并且具有良好的特异性,可以很好地将新的甲型H1N1与传统的甲型H1N1以及H3N2、H5N1、H6N2和H9N2等流感病毒区分.多重实时RT-PCR可以检测到10个拷贝的模板,灵敏度接近检测方法的极限.检测时间短,从加样到反应结束只需要90 min.在对243例发热病人临床样品检测过程中发现7例阳性,1351份猪临床样品检测中未发现阳性,该检测结果和采用中国检验检疫科学研究院研制的试剂盒获得的检测结果一致.本研究所建立的快速、准确和高敏感性的多重实时RT-PCR方法非常适用于新型甲型H1N1流感病毒的实验室筛查.     

宁都黄鸡卵巢中卵泡生长速度的研究

试验以我省名地方鸡种－宁都黄鸡成年母鸡为研究对象，每天间隔饲喂脂类染色剂ＳｕｄａｎⅢＳｕｄａｎＢｌａｃｋ，其卵泡因其脂质被染色而形成红墨相间的染色环，根据染色环圈数判断卵泡成熟前迅速生长的天然，根据染色环半径计算出卵泡第天沉积量。