长江上游特有鱼类受威胁及优先保护顺序的定量分析

根据本课题组1997~2002年野外渔获物调查数据并结合相关文献资料,运用濒危系数、遗传损失系数和物种价值系数对长江上游16种特有鱼类的优先保护顺序进行了定量分析.结果表明,达到一级急切保护的有达氏鲟(Acipenser dabryanus)、鲈鲤(Percocypris pingi)2种;达到二级急切保护的有宜宾鲴(Xenocypris fangi)、齐口裂腹鱼(Schizothorax prenanti)、四川白甲鱼(Onychostoma angustistomata)及云南鲴(Xenocypris

从线粒体DNA控制区核苷酸序列论达式鲟、亚洲和北美洲中吻鲟的分类地位(英文)

尽管古老的鲟形目鱼类的分类及系统演化一直是中外学者感兴趣的研究课题 ,但迄今仍有诸多谜团未解。其中 ,关于亚洲远东地区和北美地区的中吻鲟 (Acipensermedirostris)的分类地位争论已久。长江水系的达式鲟 (A .dabryanus)和中华鲟 (A .sinensis)及其它鲟属 (Acipenser)鱼类之间的亲缘关系近年来也有异议。为了给上述争议提供更多的科学依据 ,作者测定了线粒体DNA (mtDNA)控制区(D loop) 的核苷酸序列 ,并进行了分子系统学和遗传差异分析。研究结果表

湖鲟微卫星DNA引物应用于中华鲟亲子关系分析的初步研究

利用湖鲟(Acipenser fulvescens)的4对微卫星引物对中华鲟随机个体样本进行PCR扩增,分析电泳结果发现,4对引物均可在中华鲟个体中得到稳定的同源序列,其中2对引物所探测到的等位基因数目较多,在个体间表现出较高的多态性,利用它们产生的DNA指纹图谱,能够对1999年度获得的中华鲟亲鱼样本进行有效的个体区分。并且这两对湖鲟的微卫星引物在对1999年度已知亲本的同一家系中的中华鲟随机个体的分析中,表现为按照孟德尔方式进行共显性遗传。证明这2对微卫星引物可以用于鉴别中华鲟人工放流个体和自然繁殖个

中华鲟、白鲟组织生化成分分析初报

<正> 中华鲟(Acipenser sinensis Cray)隶属鲟形目、鲟科,在生态类群中属河海洄游鱼类,主要分布于我国长江,也见于渤海(烟台)、黄河下游、钱塘江、闽江及珠江等水域。白鲟(Psephurus gladius Martens)隶属鲟形目、白鲟科,也是一种河海洄游性鱼类,主要分布在长江水系中,自四川宜宾至江苏崇明,有时见于大型湖泊(如洞庭湖)。对于这两种我国特有、珍稀、大型的经济鱼类的形态,解剖、地理分布及生态等方面许多研究者曾作过大量的工作,积累了系统的资料(张春霖1928、伍献文192

长江中游鱼类的复殖吸虫Ⅰ.鲟拟动殖吸虫(动殖科)新属、新种的描述

<正> 从1981到1983年,作者等曾多次在湖北省宜都县和黄冈县团风镇两地,从事长江中游鱼类寄生吸虫的调查研究。在70多种鱼中,获得了一批吸虫标本,将陆续整理后发表。本文首先报告在中华鲟Acipenser sinensis Gray中发现的动殖科Zoogonidae Odhner,1911一新属、新种吸虫。动殖科吸虫在我国发现很少,迄今为止,仅顾昌栋、申纪伟(1979,1983),汪溥钦

Molecular characterization of Chinese sturgeon gonadotropins and cellular distribution in pituitaries of mature and immature individuals

Chinese sturgeon (Acipenser sinensis) is a rare and endangered species, and also an important resource for the sturgeon aquaculture industry. To understand molecular characterization of Chinese sturgeon gonadotropins (GTHs), we cloned the full-length cDNAs of gonadotropin subunits common alpha (GTH-alpha), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from a pituitary cDNA library of mature female. Two subtypes of GTH-alpha were identified. The nucleotide sequences of A. sinensis common alpha I (AsGTH-alpha I), common alpha II (AsGTH-alpha II), FSH beta (AsFSH beta) and LH beta (AsLH beta) subunit cDNAs are 345, 363, 387 and 414 bp in length, and encode mature peptides of 115, 121, 129 and 138 aa, respectively. Then, three polyclonal antibodies were prepared from the in vitro expressed AsGTH-alpha I, AsFSH beta and AsLH beta mature proteins, respectively. Significant expression differences were revealed between immature and mature sturgeon pituitaries. Western blot detection and immunofluoresence localization revealed the existence of three-gonadotropin subunits (AsGTH-alpha, AsFSH beta and AsLH beta) in mature sturgeon pituitaries, but only AsFSH beta was detected in immature individual pituitaries during early stages in the sturgeon life, and obvious difference was observed between males and females. In males, AsFSH beta was expressed in 4-year-old individuals, whereas in females, AsFSH beta was just expressed in 5-year-old individuals. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Molecular phylogenetic systematics of twelve species of acipenseriformes based on mtDNA ND4L-ND4 gene sequence analysis

Acipenseriformes is an endangered primitive fish group, which occupies a special place in the history of ideas concerning fish evolution, even in vertebrate evolution. However, the classification and evolution of the fishes have been debated. The mitochondrial DNA (mtDNA) ND4L and partial ND4 genes were first sequenced in twelve species of the order Acipenseriformes, including endemic Chinese species. The following points were drawn from DNA sequences analysis: (i) the two species of Huso can be ascribed to Acipenser; (ii) A. dabryanus is the mostly closely related to A. sinensis, and most likely the landlocked form of A. sinensis; (iii) genus Acipenser in trans-Pacific region might have a common origin; (iv) mtDNA ND4L and ND4 genes are the ideal genetic markers for phylogenetic analysis of the order Acipenseriformes.

Growth performance of juvenile white sturgeon as affected by feeding regimen

Juvenile (mean +/- SE, 8.6 +/- 0.1 g) white sturgeon Acipenser transmontanus were fed for 8 weeks under one of six feeding regimens: continuously 24 h/d (C24); continuously 12.8 h/d during the day (C12/D), continuously 12.8 h/d at night (C12/N), 6 meals/d (M6), 4 meals/d (M4), and 2 meals/d (M2). Specific growth rate, feed efficiency, and body lipid content were significantly (P < 0.05) affected by the feeding regimen. These variables were highest in the C24 group and lowest in the M2 group; fish in the M6 group showed the second best performance. Specific growth rate and feed efficiency in terms of wet weight in the M6 groups were not significantly different from those in the C24 groups, but specific growth rate in terms of energy and energy retention efficiency were significantly lower. Feeding regimen had no effect on condition factor, hepatosomatic index, coefficient of variation in final body weight, and protein and ash contents. There was no significant difference in these indexes between 12.8-h/d continuous feeding by day or by night. It was concluded that continuous feeding for 24 h/d was the optimum feeding regimen for juvenile white sturgeon.

Effect of ration and body size on the energy budget of juvenile white sturgeon

Growth and energy budget were measured for three sizes(2.4, 11.1 and 22.5 g) of juvenile white sturgeon Acipenser transmontanus held at 18.5 degrees C and fed tubificid worms at different levels ranging from starvation to ad libitum. For each size-class, specific growth rate increased linearly with increasing ration, and conversion efficiency was highest at the maximum ration. Growth rate decreased with increasing fish size at the maximum ration, but increased with size al each restricted ration. Conversion efficiency increased with increasing ration for each size-class and was usually highest at the maximum ration. Faecal production accounted for 3.2-5.2% of food energy. The proportion of food energy lost in nitrogenous excretion decreased with increasing ration. With increases in ration, the allocation of metabolizable energy to metabolism decreased, while that to growth increased. Fish size had no significant effect on the allocation of metabolizable energy to metabolism or growth. Al the maximum ration, on average 64.9% of metabolizable energy was spent on metabolism, and 35.1% on growth. (C) 1996 The Fisheries Society of the British Isles

UROTENSIN II FROM THE RIVER LAMPREY (LAMPETRA-FLUVIATILIS), THE SEA LAMPREY (PETROMYZON-MARINUS), AND THE PADDLEFISH (POLYODON SPATHULA)

Urotensin II was isolated from extracts of the whole brain of the river lamprey (Lampetra fluviatilis) and the sea lamprey (Petromyzon marinus). The primary structure of the peptide from both species is the same (Asn-Asn-Phe-Ser-Asp-Cys-Phe-Trp-Lys-Tyr-Cys-Val) and this amino acid sequence is identical to that of urotensin II from the dogfish and skate. Consistent with previous morphological studies indicating that the Agnatha lack a caudal neurosecretory system, urotensin II was not detected in an extract of P. marinus spinal cord. The data suggest that the urotensin II may have functioned in the earliest vertebrates as a neurotransmitter/neuromodulator in the central nervous system rather than as a neurohormone of the caudal neurosecretory system. Urotensin II was also isolated from an extract of the spinal cord of a chondrostean fish, the paddlefish (Polyodon spathula). The primary structure of the paddlefish urotensin II (Gly-Ser-Thr-Ser-Glu-Cys-Phe-Trp-Lys-Tyr-Cys-Val) is the same as that of another chondrostean, the sturgeon (Acipenser ruthenus). The study provides further evidence for a widespread distribution of urotensin II in vertebrate species and suggests that the primary structure of the peptide is better conserved in these phylogenetically ancient fish than in teleosts. (C) 1995 Academic Press, Inc.

Extensive genome duplications in sturgeons:New evidence from microsatellite data

Summary: Genome duplications and polyploidization events are thought to have played relevant roles in the early stages of vertebrate evolution, in particular near the time of divergence of the lamprey lineage. Additional genome duplications, specifically in ray-finned fish, may have occurred before the divergence of the teleosts. The role of polyploidization in vertebrate genome evolution is a thriving area of research. Sturgeons (order Acipenseriformes) provide a unique model for the investigation of genome duplication, with existing species possessing 120, 250 or 360 chromosomes. In the present study, data from 240 sturgeon specimens representing 11 species were used for analysis of ploidy levels. Allele numbers were assessed at eleven microsatellite loci. The results provide further evidence for functional diploidy, tetraploidy and hexaploidy in species possessing 120, 250 and 360 chromosomes, respectively. The analysis also uncovered novel evidence for functional hexaploidy in the shortnose sturgeon (Acipenser brevirostrum). In conclusion, the process of functional genome reduction is demonstrated to be an on-going process in this fish lineage. © 2013 Blackwell Verlag GmbH.

Purificação e caracterização de proteínas Gla nos modelos peixe e mamífero

Dissertação de Mestrado, Biologia Molecular e Microbiana, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2010

Antioxidant defenses and biochemical changes in the neotropical fish pacu, Piaractus mesopotamicus: Responses to single and combined copper and hypercarbia exposure

This study investigated the potentially detrimental effects of copper and elevated aquatic CO2 (hypercarbia), alone or in combination, on pacu, Piaractus mesopotamicus. Fish were exposed for 48 h to control (no copper addition in normocarbia), to 400 mu g Cu2+L-1, to hypercarbic (1% CO2; PCO2=6.9 mm Hg) water and to 400 mu g Cu2+L-1+ hypercarbia. In liver the single factors caused an increase in lipid hydroperoxide concentration that was not observed when the factors were combined. Copper exposure elicited increased hepatic superoxide dismutase activity, irrespective of aquatic CO2 level. On the other hand, the effects of copper on hepatic glutathione peroxidase activity were dependent on water CO2 levels. The two stressors combined did not affect hepatic catalase activity. Hypercarbic water caused a decline in plasma glucose concentration, but this was not observed when hypercarbia was combined with copper exposure. Copper caused a decrease in branchial Na+/K+-ATPase activity that was independent of water CO2 level. Copper caused an increase in branchial metallothionein concentration that was independent of water CO2 level. Thus, branchial metallothionein and Na+/K+-ATPase were effective biomarkers of copper exposure that were not affected by water CO2 level. (C) 2012 Elsevier Inc. All rights reserved.

Seasonal Distribution and Movements of Shortnose Sturgeon and Atlantic Sturgeon in the Penobscot River Estuary, Maine

Relatively little is known about the distribution and seasonal movement patterns of shortnose sturgeon Acipenser brevirostrum and Atlantic sturgeon Acipenser oxyrinchus oxyrinchus occupying rivers in the northern part of their range. During 2006 and 2007, 40 shortnose sturgeon (66-113.4 cm fork length [FL]) and 8 Atlantic sturgeon (76.2-166.2 cm FL) were captured in the Penobscot River, Maine, implanted with acoustic transmitters, and monitored using an array of acoustic receivers in the Penobscot River estuary and Penobscot Bay. Shortnose sturgeon were present year round in the estuary and overwintered from fall (mid-October) to spring (mid-April) in the upper estuary. In early spring, all individuals moved downstream to the middle estuary. Over the course of the summer, many individuals moved upstream to approximately 2 km of the downstream-most dam (46 river kilometers [rkm] from the Penobscot River mouth [rkm 0]) by August. Most aggregated into an overwintering site (rkm 36.5) in mid-to late fall. As many as 50% of the tagged shortnose sturgeon moved into and out of the Penobscot River system during 2007, and 83% were subsequently detected by an acoustic array in the Kennebec River, located 150 km from the Penobscot River estuary. Atlantic sturgeon moved into the estuary from the ocean in the summer and concentrated into a 1.5-km reach. All Atlantic sturgeon moved to the ocean by fall, and two of these were detected in the Kennebec River. Although these behaviors are common for Atlantic sturgeon, regular coastal migrations of shortnose sturgeon have not been documented previously in this region. These results have important implications for future dam removals as well as for rangewide and river-specific shortnose sturgeon management.

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 220 - Anfrage nach einer Übersetzung von Baltasar Graciáns "Criticon" von 1698 aus dem Privatbesitz Schopenhauers

u.a.: Suche nach einem Verleger; spanisches Zitat aus einer Ausgabe der "Historia de la literatura espanola"; Bekanntmachung eigener Übersetzung von Baltasar Graciáns "Criticon" ins Deutsche; Johann Gottlob von Quandt;