浙江淡水水母一新亚种--永康桃花水母

2002年11月18日于浙江省永康市花街镇一池塘采得多个淡水水母标本。其触手伸展时呈细长线状,按其长短及着生位置分为6级。伞缘触手479～719条,平均608条。4条主辐触手不显著长于其它触手,长约为伞径的3/5;4个生殖腺褐黄色,着生在主辐管下方,呈光滑的三角扁囊状,向下有一细长的指状突起;平衡囊管状,数目为163～208个,平均183个;伞径大;触手数目、触手级数、平衡囊数目多,这些特征与桃花水母属已知种和亚种有明显区别,兹订为一新亚种,永康桃花水母(CraspedacustasowerbyiyongkangensisWangetXu,subsp.nov.)     

浙江淡水水母一新亚种--永康桃花水母

2002年11月18日于浙江省永康市花街镇一池塘采得多个淡水水母标本。其触手伸展时呈细长线状,按其长短及着生位置分为6级。伞缘触手479～719条,平均608条。4条主辐触手不显著长于其它触手,长约为伞径的3/5;4个生殖腺褐黄色,着生在主辐管下方,呈光滑的三角扁囊状,向下有一细长的指状突起;平衡囊管状,数目为163～208个,平均183个;伞径大;触手数目、触手级数、平衡囊数目多,这些特征与桃花水母属已知种和亚种有明显区别,兹订为一新亚种,永康桃花水母(CraspedacustasowerbyiyongkangensisWangetXu,subsp.nov.)     

颤蚓对水田沉积物颗粒垂直运移的生物扰动效应(摘要)(英文)

[目的]研究颤蚓扰动对水田沉积物颗粒垂直运移的作用,探讨底栖环节动物在水层-底栖界面耦合过程中的生物扰动作用和机制。[方法]以化学性质稳定的玻璃珠作为示踪颗粒,对比分析水田沉积物颗粒垂直运移在有/无颤蚓活动时的差异。[结果]颤蚓扰动10d后,沉积物表层示踪颗粒有41.3%向下迁移,最大迁移深度为9.4cm,垂直迁移率为1.370×10-3(g.cm2.d)。6cm深处的示踪颗粒分别有25.8%和17.3%在扰动后向上和向下迁移,向上和向下最大迁移距离分别为5.2和2.7cm,垂直向上和向下迁移率分别为8.557×10-4和5.738×10-4(g.m2.d)。[结论]颤蚓通过自身的活动,使水田表层和深层沉积物颗粒在垂直方向上发生运移,改变了沉积环境。     

Dynamics of experimental production of Thelohanellus hovorkai (Myxozoa: Myxosporea) in fish and oligochaete alternate hosts

The dynamics of development and production of Thelohanellus hovorkai (Myxozoa) were examined to investigate factors inducing haemorrhagic thelohanellosis in carp, Cyprinus carpio L. Fresh actinospores of T. hovorkai were harvested from the oligochaete alternate host, Branchiura sowerbyi, and used for infection experiments with myxosporean-free carp. Visualization of actinospores by fluorescent labelling revealed that sporoplasms penetrated the gill filaments of carp immersed in an actinospore suspension as early as 30 min post-exposure (PE). Plasmodia of T. hovorkai developed in the connective tissues of various organs and matured 3-5 weeks PE; dispersion of myxospores from degenerate plasmodia occurred 5-7 weeks PE. Challenges with a high dose of actinospores (4.5 x 10(6) spores per fish) resulted in the onset of disease, which was more easily achieved by the oral intubation of actinospores than by immersion in an actinospore suspension. Actinosporean-free B. sowerbyi were exposed to different densities of myxospores (10(4)-10(6) spores per oligochaete) and subsequently reared at different temperatures (15, 20, 25 degrees C). At 20 and 25 degrees C, actinospore releases were first detected 40-43 days PE, with multiple peaks of release (max. 7 x 10(5) actinospores day(-1)) during the next 60 days. We concluded that the developmental cycle of T. hovorkai was completed within 3-5 months at 20-25 degrees C, and that the ingestion of large numbers of actinospores orally, possibly by feeding on infected oligochaetes, resulted in a disease condition in carp.     

苏氏尾鳃蚓寄生放射孢子虫的形态描述

笔者在江苏省溧阳某鲫养殖塘底泥采集的苏氏尾鳃蚓(Branchiura sowerbyi)中检测到一种放射孢子虫,经形态特征观察和比较分析,鉴定其隶属于棘放射孢子虫(Echinactinomyxon)类群。该放射孢子虫孢体呈圆柱形,长18.95μm(18.5～19.4μm),宽9.55μm;极囊长6.11μm(5.97～6.26),宽2.98μm(2.38～3.58);尾柄长161.2μm(161.2～167.16),宽3.24μm(2.98～3.58),孢体与尾柄的夹角约为160°。将其与国内外文献中已记述的放射孢子虫作比较研究,发现其在寄生宿主、形态大小、尾柄特征等方面有明显差异。本文描述的该类放射孢子虫为国内外首次报道。     

索式桃花水母全长cDNA文库的构建

[目的]构建索式桃花水母的全长cDNA文库,为桃花水母的生长、发育、衰老过程功能基因的进一步筛选、克隆和表达奠定基础。[方法]利用RNAiso试剂盒提取桃花水母的总RNA,采用SMART技术合成全长cDNA,经SfⅠi酶切消化后,将cDNA克隆到质粒载体pDNR-LIB,并对cDNA文库进行质量评价。[结果]经鉴定,原始文库的滴度为7.9×10^5cfu/ml,库容量约为1.0×10^6cfu。随机挑取28个克隆,经PCR快速鉴定,插入片段大小在0.5～2.5kb,平均大小在1.0kb左右,重组率达94%,表明获得了高质量的桃花水母cDNA文库。[结论]该试验成功构建了桃花水母cDNA文库,其cDNA原始文库的库容,根据真核生物能够满足建库的要求,同时文库的cD-NA插入片段序列是完整的,从而证实构建的文库质量较好,可以用于桃花水母目的基因的筛选。     

福州地区发现的一种桃花水母的分类鉴定

采用形态鉴定和18SrDNA基因序列分析技术对采自福州一金鱼养殖场蓄水池中的桃花水母（freshwaterj ellyfish）进行分类鉴定。结果显示：样品的平衡囊管状,主辐触手较其它触手长,刺丝囊疣为乳突状呈螺旋状或环状排列,形态鉴别特征与己知的索氏桃花水母及其亚种相同;触手密集度11．06±0．71,平衡囊密集度5．66±0．43,与索氏桃花水母也最相近;样品18SrDNA序列与GenBank中索氏桃花水母有99％的相似性。因此,经鉴定本次在福州地区发现的桃花水母为索氏桃花水母（Craspedacusta sowerbyi Lankester, 1880）。