史氏鲟的生态习性及其保护性利用

史氏鲟是中国现存鲟鱼中最具经济价值的优质珍稀鱼类,集观赏、美食于一体,具有个体大、寿命长、幼鱼成活率高、生长速度快等特点,经驯化后能迅速生长,对环境有较强的适应性;通过对史氏鲟生态习性、饲料和加工的研究,探讨史氏鲟繁养及利用技术;在对史氏鲟进行保护性利用的前提下深入研究史氏鲟的养殖和加工,为其他鲟鱼的研发积累经验。     

中国大鲵研究概况

中国大鲵(Andrias davidianus)为我国特有物种,也是国家二类保护水生野生动物.野生大鲵多栖息在山区溪流里,喜穴居,怕光怕声,以鱼蟹等水生动物为食,从数量上看,以陕西秦岭山区居多.大鲵经济价值极高,在美食、保健、医药、观赏等方面均具有广泛开发利用的前景,因而颇受社会各界关注.近年来对大鲵的科学研究涉及多个...     

大鲵皮肤色素提取工艺及抗氧化研究

为优化大鲵皮肤黑色素的提取工艺条件,探讨大鲵皮肤黑色素组成成分及体外抗氧化活性,采用酶法和碱溶酸沉法提取大鲵皮肤黑色素,以氢氧化钠浓度、液料比、提取温度为影响色素提取率因素,优化黑色素提取工艺条件,用紫外-可见光谱仪、红外光谱仪和超高效液相质谱仪测定黑色素的光谱特性,测定其抗氧化性。结果表明:大鲵皮肤黑色素最佳提取工艺条件为氢氧化钠浓度1.5 mol/L、液料比1∶15、提取温度45℃,黑色素提取率达0.65%。大鲵皮肤黑色素的紫外最大吸收波长为214 nm,由真黑色素和脱黑色素两种色素组成,其对超氧阴离子自由基的清除率为30.51%,对羟基自由基的清除率为54.17%。大鲵皮肤黑色素具有一定的体外抗氧化能力。     

患病大鲵中弗氏柠檬酸杆菌的分离与鉴定

【目的】确定导致大鲵(Andrias davidianus)细菌性感染死亡的病原。【方法】从大鲵肝脏中分离细菌,通过Biolog微生物自动鉴定系统及分子生物学方法对纯培养的细菌进行鉴定,再用大鲵和鲫鱼分别进行人工感染试验,以确定分离菌的致病性,同时对分离到的病原菌进行药物敏感试验。【结果】从患病大鲵肝脏中分离到一株致病菌JZ01,经人工感染健康大鲵,可复制与自然发病相同的症状,且从人工感染病鲵体内再次分离到相同的病原菌。该致病菌对健康鲫鱼也有致病性。经Biolog微生物自动鉴定系统的鉴定,以及进一步的16S rDNA基因序列和系统发育分析都表明,此致病菌为弗氏柠檬酸杆菌。药物敏感性试验表明,该菌株对氨曲南、头孢三嗪、先锋噻肟等9种药物高度敏感。【结论】弗氏柠檬酸杆菌是大鲵的一种致病菌。本文在国内外首次报道了该菌对大鲵具有致病性。     

Genetic diversity of Chinese giant salamander (Andrias davidianus) based on the novel microsatellite markers

Chinese giant salamander (Andrias davidianus) is a rare amphibian species in the world. Microsatellite markers are a promising tool for accurate estimation population structure and genetic diversity. In this paper, we isolated novel microsatellite marker for Chinese giant salamander using fast isolation by AFLP of sequences containing repeats (FIASCO) method. More than 50% sequences in 132 clones had repeat number over ten times with di or trinucleeotide repeat except of (GA)₁₂. Seventy pairs of primers were designed and eleven polymorphic microsatellite loci were characterized for wild and cultivated Chinese giant salamander populations. The allele number was from 3 to 9 in different loci. Polymorphism information content was from 0.544 to 0.702 in cultivated population. The results implied more alleles and PIC were in the wild population than cultivated population. The observed heterozygosities in two populations were higher than 0.553. The data analysis suggested that the cultivated population has lower genetic diversity than wild population, which it??s perhaps owing to inbreeding in artificial breeding. To our knowledge, it??s the first time to isolated microsatellite markers for Chinese giant salamander. The result indicated that the markers were suitable for the population genetic analysis of Chinese giant salamander.     

大鲵保护生物学及其研究进展

大鲵（Andrias davidianus)为我国特有的珍稀两栖动物,已列入国家二级保护动物名录,并列入CITES公约附录Ⅰ中。自20世纪50年代起,由于过度收购、非法捕杀和栖息地丧失等原因,大鲵种群数量下降极为严重,湖南、安徽等地的大鲵产量在20世纪50年代至70年代下降超过80％,分布区也极度萎缩,形成了12块岛屿状区域,目前分布于以我国中部山区的长江流域为主的17个省区。部分已建立的大鲵保护区经费短缺,人员不足,管理不力,状况不容乐观。非法捕捉和栖息地丧失仍是威胁大鲵生存的主要因素,保护管理力度还需进一步加强。     

大鲵皮肤cDNA文库构建及Arpc5l基因cDNA序列和组织表达分析

以健康大鲵背部皮肤为材料,采用Smart技术构建大鲵皮肤cDNA文库,经检测文库容量为150×106 cfu,文库重组率为98%,插入片段平均长度约为1 kb. 通过对大鲵皮肤cDNA文库的随机筛选,分离获得了大鲵肌动蛋白相关2/3复合物亚基 5样蛋白(Arp2/3 complex subunit 5-like, Arpc5l)基因cDNA序列.生物信息学分析表明,大鲵Arpc5l基因全长cDNA为 699 bp, 包含459 bp的开放阅读框,分子量为17 154.36,等电点(pI)为5.43;该基因编码的Arpc5l蛋白分别在7-29 AA处和44-66 AA处具有跨膜结构域及多种二级结构,且三级结构与Arp2/3 complex家族成员相似. 实时定量PCR结果表明,该基因在大鲵皮肤、肌肉、肠、肝、脾、肺、胃以及肾等组织中广泛表达,且在肾、肠、肌肉中的表达量极显著高于其它组织(P<0.01). 进化分析结果表明, 大鲵Arpc5l氨基酸序列和小鼠(77％)等陆生动物同源性最高,和爪蟾同源性为73％,大鲵处于水生到陆生之间的过渡类型,且与陆生动物的亲缘关系更近.     

Determining threatened species distributions in the face of limited data: Spatial conservation prioritization for the Chinese giant salamander (Andrias davidianus)

The purpose of this study was to determine whether limited occurrence data for highly threatened species can provide useful spatial information to inform conservation. The study was conducted across central and southern China. We developed a habitat suitability model for the Critically Endangered Chinese giant salamander (Andrias davidianus) based on one biotic and three abiotic parameters from single‐site locality records, which represent the only relevant environmental data available for this species. We then validated model quality by testing whether increased percentage of predicted suitable habitat at the county level correlated with independent data on giant salamander presence. We randomly selected 48 counties containing historical records which were distinct from, and independent of, the single‐site records used to develop the model, and 47 additional counties containing >50% predicted suitable habitat. We interviewed 2,812 respondents near potential giant salamander habitat across these counties and tested for differences in respondent giant salamander reports between counties selected using each method. Our model predicts that suitable giant salamander habitat is found widely across central and southern China, with counties containing ≥50% predicted suitable habitat distributed in 13 provinces. Counties with historical records contain significantly more predicted suitable habitat than counties without historical records. There are no statistical differences in any patterns of respondent giant salamander reports in surveyed counties selected from our model compared with the areas of known historical giant salamander distribution. A Chinese giant salamander habitat suitability model with strong predictive power can be derived from the restricted range of environmental variables associated with limited available presence‐only occurrence records, constituting a cost‐effective strategy to guide spatial allocation of conservation planning. Few reported sightings were recent, however, with most being over 20 years old, so that identification of areas of suitable habitat does not necessarily indicate continued survival of the species at these locations.     

大鲵栖息地环境的初步研究

2001年4月至8月,对湖南省壶瓶山自然保护区河流中大鲵(Andrias davidianus)的栖息洞穴,首次使用量化指标进行分析。通过主成分分析发现,大鲵栖息洞穴处的水深、洞口宽、水流速度和河底的组成是影响大鲵选择洞穴的主要因子,而海拔高度和洞口高的影响不大。同时,对重庆市酉阳县、陕西省太白县、河南省卢氏县大鲵自然保护区和新安县青要山大鲵自然保护区大鲵的栖息河流特征进行了调查。结果表明大鲵的栖息河流类型可分为溪流、U型河流、平底型河流和暗河4类,而且大鲵对其栖息洞穴的质量要求较高。     

黄山市大鲵资源古今及保护

本文记述了黄山市大鲵资源分布及其演变概况,大鲵资源枯竭的原因和对保护大鲵资源的建议。     

多普勒B超鉴定中国大鲵性别

首次报道了从影像学水平上鉴定中国大鲵性别的研究结果。采用多普勒B超,常规方法直接扫描雌雄中国大鲵腹部,并记录大鲵的精巢或卵巢的形状、内部回声。实验结果表明,雌雄中国大鲵的检测结果存在明显的差畀,在雄性中国大鲵的腹部,可检测到精巢组织;在雌性中国大鲵的腹部,可检测到为卵巢组织和卵泡。初步分析了实验结果,并认为将多普勒B超鉴定法与泄殖孔法鉴定相结合可以作为中国大鲵性别鉴定的可靠方法。     

甘草对大鲵抗嗜水气单胞菌感染的作用

通过投喂甘草提取物, 研究了甘草对大鲵(Andrias davidianus)抗嗜水气单胞菌(Aeromonas hydrophila)感染的作用。连续投喂56d, 从28d开始, 药物组血清溶菌酶活性先升后降, 呈抛物线趋势, 低剂量组在42d出现最大值(158.4±34.7) U/mL, 高剂量组在35d出现最大值(178.3±28.8) U/mL, 两者都显著高于同期对照组(P<0.05)。药物组在最后两次采样期, 即42d和56d时, 肾脏巨噬细胞吞噬活性显著高于对照组(P<0.05)。低剂量组和高剂量组最大值均出现在42d, 分别为(59.4±8.5)%和(58.4±5.2)%。同期相比, 药物组白细胞比容值均高于对照组。其中, 高剂量组在28d时白细胞比容值为(5.8±1.7)%, 低剂量组在56d时为(5.5±0.8)%, 高剂量组在56d时为(5.9±1.7)%, 三者都显著高于同期对照组(P<0.05)。药物组和对照组的脾脏脏器系数之间没有显示出显著差异。最后一次采样(56d)后人工感染嗜水气单胞菌, 对照组死亡率为90%, 低剂量组和高剂量组都为60%, 均低于对照组, 而药物组免疫保护率为33.3%, 也都高于对照组。结果表明, 投喂甘草提取物可在一定程度上提高大鲵对嗜水气单胞菌的抗性。     

配合饲料和鲢鱼肉对大鲵生长的比较试验

为探讨人工配合饲料和鲢鱼肉对大鲵生长、消化和抗氧化能力的影响,试验选取初始体重为(20.99±0.15) g的大鲵幼体48尾,随机分成2组,每组3个重复,每个重复8尾,分别投喂人工配合饲料(粗蛋白55.67%,粗脂肪6.83%)和鲢鱼肉(粗蛋白18.03%,粗脂肪4.11%)共92d。结果显示:(1)饲料组大鲵的增重率(WGR)、特定生长率(SGR)、蛋白质沉积率(PRR)和肌肉蛋白质合成能力均显著高于鱼肉组,饲料系数(FCR)和存活率(SR)在两个试验组之间无显著差异(P>0.05)。(2)在大鲵摄食人工配合饲料后,全鲵粗蛋白、皮肤胶原蛋白及粗灰分含量均显著高于鱼肉组(P<0.05),而全鲵水分、粗脂肪与肌肉的粗脂肪和粗灰分含量显著低于鱼肉组(P<0.05)。(3)饲喂鲢鱼肉的大鲵胃蛋白酶活性显著高于饲料组(P<0.05),而两个试验组的胃H⁺-K⁺-ATP酶和肠道消化酶活性均无显著差异(P>0.05)。(4)饲喂人工配合饲料的大鲵肝脏总抗氧化能力(TAOC)和超氧化物歧化酶(SOD)活性显著高于鱼肉组(P&l...     

大鲵免疫分子CD9的克隆与鉴定

CD9是4次跨膜蛋白家族成员,对机体的免疫调控发挥着重要作用．本文首次报道了大鲵CD9的鉴定及其对免疫刺激的应答．大鲵CD9（Chinese giant salamander CD9, cgsCD9）由232个氨基酸组成,被4个跨膜结构域分割成1个胞内环、2个胞外环和2个短的胞内末端,这是4次跨膜蛋白的主要结构特征．1个糖基化位点NDS、1个CCG模体和7个半胱氨酸残基保守地存在于cgsCD9．cgsCD9与其它脊椎动物CD9具有最高77%氨基酸序列一致性,并与两栖动物CD9归属一族．实时定量RT-PCR结果显示,cgsCD9在大鲵中分布广泛,脾脏组织的表达水平最高,并且脂多糖能显著提高cgsCD9 mRNA的表达．过表达于Jurkat细胞中的cgsCD9能促进核因子κB的活化以及白介素-6的表达,而cgsCD9的作用在CCG模体突变为AAA后几乎丧失．上述结果表明,cgsCD9在大鲵抵抗细菌的免疫应答中发挥重要作用．     

Historical museum collections clarify the evolutionary history of cryptic species radiation in the world's largest amphibians

Inaccurate taxonomic assessment of threatened populations can hinder conservation prioritization and management, with human‐mediated population movements obscuring biogeographic patterns and confounding reconstructions of evolutionary history. Giant salamanders were formerly distributed widely across China, and are interpreted as a single species, Andrias davidianus. Previous phylogenetic studies have identified distinct Chinese giant salamander lineages but were unable to associate these consistently with different landscapes, probably because population structure has been modified by human‐mediated translocations for recent commercial farming. We investigated the evolutionary history and relationships of allopatric Chinese giant salamander populations with Next‐Generation Sequencing methods, using historical museum specimens and late 20th‐century samples, and retrieved partial or near‐complete mitogenomes for 17 individuals. Samples from populations unlikely to have been affected by translocations form three clades from separate regions of China, spatially congruent with isolation by either major river drainages or mountain ranges. Pliocene–Pleistocene divergences for these clades are consistent with topographic modification of southern China associated with uplift of the Qinghai‐Tibet Plateau. General Mixed Yule Coalescent model analysis indicates that these clades represent separate species: Andrias davidianus (Blanchard, 1871) (northern Yangtze/Sichuan), Andrias sligoi (Boulenger, 1924) (Pearl/Nanling), and an undescribed species (Huangshan). Andrias sligoi is possibly the world's largest amphibian. Inclusion of additional reportedly wild samples from areas of known giant salamander exploitation and movement leads to increasing loss of biogeographic signal. Wild Chinese giant salamander populations are now critically depleted or extirpated, and conservation actions should be updated to recognize the existence of multiple species.     

Heterogeneous Vesicles in Mucous Epithelial Cells of Posterior Esophagus of Chinese Giant Salamander (Andrias Davidianus)

The Chinese giant salamander belongs to an old lineage of salamanders and endangered species. Many studies of breeding and disease regarding this amphibian had been implemented. However, the studies on the ultrastructure of this amphibian are rare. In this work, we provide a histological and ultra-structural investigation on posterior esophagus of Chinese giant salamander. The sections of amphibian esophagus were stained by hematoxylin & eosin (H&E). Moreover, the esophageal epithelium was observed by transmission electron microscopy (TEM). The results showed that esophageal epithelium was a single layer epithelium, which consisted of mucous cells and columnar cells. The esophageal glands were present in submucosa. The columnar cells were ciliated. According to the diverging ultrastructure of mucous vesicles, three types of mucous cells could be identified in the esophageal mucosa: i) electron-lucent vesicles mucous cell (ELV-MC); ii) electron-dense vesicles mucous cell (EDV-MC); and iii) mixed vesicles mucous cell (MV-MC).Key words: Amphibian, esophagus, ultrastructure, mucous cells, heterogeneous vesicles     

中国大鲵肝脏的超微结构

应用透射电镜对中国大鲵的肝脏进行了超微结构研究.观察表明,大鲵肝不具肝小叶,与其他脊椎动物有所不同.肝细胞含有单个卵圆形的核;细胞质内含有粗面内质网、高尔基囊泡、线粒体、糖原颗粒和脂滴等细胞器和内含物.胆小管由两个相邻肝细胞质膜凹陷围成,而肝血窦则由内皮细胞的胞质构成.胆小管腔和窦周隙内浸润许多由肝细胞发出的微绒毛结构.还发现了枯否氏细胞和贮脂细胞.还讨论了中国大鲵肝脏的一般形态结构特点.     

Transcriptome Profiles in the Spleen of the Chinese Giant Salamander (Andrias davidianus) Challenged with Citrobacter freundii

Russian Journal of Bioorganic Chemistry - The Chinese giant salamander (Andrias davidianus) is one of the most important ecological breeding species with distinct characteristics and is cultured in...     

人工养殖大鲵全长与体重关系的回归分析

大鲵(Andrias davidianus)隶属两栖纲,有尾目,隐鳃鲵科,大鲵属,为我国特有的珍稀濒危两栖动物。目前在我国一些主要历史分布区掀起了一股大鲵养殖高潮,但是对当前养殖效果缺乏成熟的评价手段,因此本研究通过对陕西省汉中市和安康市两大鲵养殖场养殖的1530尾大鲵的体重和全长进行实际测量,利用SPSS分析软件对数据进行了回归分析。结果表明,体重与全长之间存在极显著的相关关系,体重与全长之间的关系主要表现为幂函数关系,其关系式为:Y=0.010X2.867。本研究的顺利完成,为今后评价大鲵的人工养殖效果提供了科学的方法。     

正常和蛙病毒感染后大鲵血清和黏液蛋白图谱比较分析

为了更好地了解大鲵在感染蛙病毒过程中的生理生化及抗病毒反应, 通过十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDS-PAGE) 辅以密度分析, 对大鲵正常血清和感染血清、正常黏液和感染黏液的蛋白图谱分别进行测试比较。结果显示: 在正常血清(CS)、包括自然感染血清(NS)和人工感染血清(AS)在内的感染血清中,蛋白带集中在6080 kD, 其含量超过血清蛋白总量的42%; 正常血清在1457 kD 之间有16条蛋白带: 57、53、50、43、40、38、36、31、27、26、25、22、16、15.5、15 和14 kD, 其中正常与感染血清(包括NS和AS)比较, 有10条共有蛋白带: 57、43、40、31、27、26、25、15.5、15 和14 kD和4条差异蛋白带: 53、33、22 和16 kD。正常黏液(CM)和感染黏液(NM或AM)共有11条蛋白带: 116、100、75、57、53、45、27、18、17、16和15 kD, 但感染黏液多出7 条蛋白带: 90、52、43、32、26、20 和13 kD。还有些蛋白带含量出现变化, 如45 kD条带在CM中占总蛋白量的19.3%, 而在AM中仅占总蛋白的3.8%。研究证实蛙病毒感染能导致大鲵黏液和血清蛋白图谱发生变化, 也为深入探寻两栖类抗病毒相关的蛋白生物标记提供了有价值的信息。