鄱阳湖水系鲢群体的形态差异

应用多变量形态度量学和框架结构形态学相结合的方法,对采自鄱阳湖湖口水域及赣江、信江、抚河的148尾鲢标本的10个传统可量性状和20个框架性状数据进行测量。通过聚类、主成分、判别三种多元统计方法分析得出:四个鲢群体在形态上已产生一定程度的分化,可以较明显地区分开来。     

滇池金线鲃、西畴金线鲃及其杂交F1代的形态分析

根据传统形态度量学和框架结构形态学法测量了15月龄的杂交F1代(滇池金线鲃Sinocyclocheilus grahami♀×西畴金线鲃S.xichouensis♂)以及滇池金线鲃(S.grahami)和西畴金线鲃(S.xichouensis)的10项传统可量性状数据和24项框架结构数据以及鳍条、侧线鳞和脊椎骨等可数性状数据。并用方差分析和多元统计分析法(聚类分析,判别分析和主成分分析)对三者的传统可量性状和框架结构数据进行分析。结果显示:三者的可数性状差别不大,杂交F1代体表花纹与双亲相比发生一定变化。聚类分析结果表明,杂交F1代的形态与母本滇池金线鲃形态较为相似。采用逐步判别分析方法建立了3种鱼的判别函数,判别准确率较高(90%,90%,100%)。主成分分析结果及主成分散点图显示:三者均有重叠区域不容易从形态上清楚分开,但杂交F1代明显更接近母本滇池金线鲃。结合方差分析和主成份分析发现杂交F1代与双亲不同的性状主要集中在头部和尾部。     

澜沧江多鳞荷马条鳅种群间形态差异的比较

为探讨澜沧江水系不同采集地的多鳞荷马条鳅(Homatula pycnolepis)形态差异,将168尾多鳞荷马条鳅标本按采集地分为5组;将9尾拟鳗荷马条鳅(Homatula anguillioides)和19尾无量荷马条鳅(Homatula wuliangensis)作为对照组,共计196尾荷马条鳅标本做多变量形态度量学研究。测量了13个框架特征和23个常规特征,经3次主成分分析,澜沧江多鳞荷马条鳅不同地理种群间的形态差异超出了多鳞荷马条鳅分别与拟鳗荷马条鳅和无量荷马条鳅之间的形态差异;除多鳞荷马条鳅地模标本以外,仍有3个与同属鱼类形态特征不同的种群。经进一步对比,该3个种群应是荷马条鳅属未被描记的新种。     

3个地理群体宽口裂腹鱼形态差异分析

采用多变量形态度量学方法,对托什干河、塔什库尔干河和渭干河宽口裂腹鱼(Schizothorax eurystomus)65尾个体框架结构测量中的31个形态比例指标进行了多元统计分析。结果显示:3个群体在4个可变量上存在显著差异,在12个变量上存在极显著差异。主成分分析前3个主成分贡献率分别为22.28%、13.428%和8.90%,累计贡献率为44.60%;根据前3个主成分构建的散点图显示,3个地理群体不同个体之间有个体发生重叠,3个地理种群并未形成明显的独立组群;聚类分析发现,托什干河群体和塔什库尔干河群体距离最近,最先聚为一支,后与渭干河群体汇为一大支。结果表明,托什干河群体与塔什库尔干河群体最为接近,与渭干河群体存在较大差异。     

哲罗鲑和川陕哲罗鲑群体多变量形态特征比较

为探明珍惜濒危鱼类哲罗鲑(Huchotaimen)种內及其与川陕哲罗鲑(Huchobleekeri)种间的外部形态差异,以新疆、黑龙江的哲罗鲑和陕西的川陕哲罗鲑为研究对象,采用传统形态学方法和框架度量法结合的方式,对3个群体的9个分节特征和35项标准化量度特征进行了统计分析。结果显示：(1)哲罗鲑两个地理群体在侧线鳞平均数上存在显著性差异(P<0.05),但整体上,两个群体在全部9个分节特征上均存在个体交叉,无法进行区分。川陕哲罗鲑的臀鳍分支鳍条、侧线鳞和幽门盲囊平均数显著小于哲罗鲑(P<0.05),且二者不存在个体交叉,区分明显。(2)主成分分析共筛选出4个特征值大于1的主成分,累计贡献率达88.928%,其中第一主成分贡献率最高,主要解释了3个群体的躯干斜向形态差异。构建主成分二维散点图发现, 3个群体虽能形成相对独立的组,但彼此之间仍存在个体交叉。(3)单因素方差分析显示哲罗鲑种內仅有14项主要描述头部和尾部的度量特征存在显著性差异(P<0.05),而哲罗鲑和川陕哲罗鲑之间则有29项主要描述躯干部的量度特征存在显著性差异(P<0.05)。(4)判别分析共筛...     

虹鳟不同养殖群体形态性状变异的初步研究

本文采用鱼类形态度量学和框架度量学相结合的方法，对五个不同虹鳟养殖群体（1．渤海群体2．丹麦群体3．道氏群体4．挪威群体5．加州群体）20个比例性状进行了主成分分析，结果表明：虹鳟的形态指标大致可归纳为“大小因子”、“摄食因子”、“游泳因子”、“形态因子”和“头型因子”能较完整（82．66％）地描写虹鳟的外形特征；道氏以外的4个虹鳟群体的形态学特征存在较大的相似性，道氏群体与其他4个虹鳟群体的形态差异较大；通过比较其形态性状以便评估其种内的变异以及各个性状伴随着生长而产生的变化，为今后虹鳟的选育方案设计及选择应答的预测提供参考。     

中国金线鲃鱼类的体鳞研究

本文对分布于滇桂黔三省区的18种金线的体鳞覆盖程度、侧线鳞（孔）数、体鳞大小、侧线鳞与体鳞比较、体鳞辐射沟数和辐射沟的分布等七个性状作了比较研究，证明体鳞特征可作为金线肥鱼类属种间分类的重要依据，文中对金线鱼类体鳞进化趋势作了补步探讨，证明作者将侧线鳞与体鳞一致的金线并入近金线属是合理的。此外，由鳞片结构证明无眼金线鱼与麦田河金线亲缘上较相近，可能由共同祖先分化而成。     

五种蚌的形态变异与判别分析

运用多变量形态度量学方法，采用6个形态性状对褶纹冠蚌、三角帆蚌、圆背角无齿蚌、椭圆背角无齿蚌和球形无齿蚌5种蚌的种间以及地理种群间的形态变异进行了研究。主成分分析构建了2个主成分，第一主成分受4个性状的影响，贡献率为54.17%；第二主成分受1个性状的影响，贡献率为34.08%。主成分分析和聚类分析表明，褶纹冠蚌与三解帆蚌形态相近，随圆背角无齿蚌与球形无齿蚌外形相拟。方差分析和t检验表明，褶纹冠蚌和三解帆蚌的不同地理种群分别表现出形态上变异。建立了5种蚌的判别函数，三角帆蚌和圆背角无齿蚌的判别准确率均为100%，褶纹冠蚌、椭圆背角无齿蚌和球形无齿蚌的判别准确率依次为98.92%、86.36%和96.88%，总判别准确率为97.83%。     

大口黑鲈北方亚种、佛罗里达亚种及其杂交子代的生长和形态差异分析

以大口黑鲈北方亚种和佛罗里达亚种为亲本,建立了北方亚种自交N(北方亚种♀×北方亚种♂)、佛罗里达亚种自交F(佛罗里达亚种♀×佛罗里达亚种♂)、正交子代NF(北方亚种♀×佛罗里达亚种♂)和反交子代FN(佛罗里达亚种♀×北方亚种♂)4个试验群体,并对其生长性能和形态学差异进行了比较。N、NF和FN的生长性能比较结果表明,在90～152日龄期间,3个试验群体生长速率差别不大,在152日龄后大口黑鲈北方亚种的生长速度明显快于两杂交子代。可数性状的分析结果表明,4个试验组在腹鳍、臀鳍硬棘、鳃耙和脊椎骨上均无差异;正反交子代与两亲本在背鳍条、胸鳍条、臀鳍条、尾鳍条、侧线上鳞、侧线下鳞的数量上均达到极显著差异(P0.01)。可量性状和框架结构数据的聚类分析结果表明,N和F聚为一支,NF和FN聚为一支,然后这两支再汇聚;主成分分析概括出方差贡献率较大的3个主成分,累积贡献率为71.44%,主成分1主要反映鱼体框架的变化,方差贡献率为54.90%,主成分2和主成分3主要反映鱼的头部、背部和尾部的形态变化,方差贡献率分别为11.21%和5.33%。在35个测量参数中挑选11个对判别贡献较大的参数建立4个群体的判别函数,判别准确率为83.90%～100.00%。研究结果为杂种大口黑鲈的鉴定、育种及养殖提供了科学依据。     

中国金线Ba鱼类的体鳞研究

本对分布于滇桂黔三省区的18种金线Ba的体鳞覆盖程度、侧线鳞（孔）数、体鳞大小、侧线鳞与体鳞比较、体鳞辐射沟数和辐射沟的分布等七个性状作了比较研究，证明体鳞特征可作为金线肥鱼类属种间分类的重要依据，中对金线Ba鱼类体鳞进化趋势作了初步探讨，证明作将侧线鳞与体鳞一致的金线Ba并入近金线Ba属是合理的。此外，由鳞片结构证明无眼金线Ba鱼与麦田河金线Ba亲缘上较相近，可能由共同祖先分化而成。     

Pan‐continental invasion of Pseudorasbora parva: towards a better understanding of freshwater fish invasions

In recent years, policy‐makers have sought the development of appropriate tools to prevent and manage introductions of invasive species. However, these tools are not well suited for introductions of non‐target species that are unknowingly released alongside intentionally‐introduced species. The most compelling example of such invasion is arguably the topmouth gudgeon Pseudorasbora parva, a small cyprinid species originating from East Asia. A combination of sociological, economical and biological factors has fuelled their rapid invasion since the 1960s; 32 countries (from Central Asia to North Africa) have been invaded in less than 50 years. Based on a combination of monitoring surveys (2535 populations sampled) and literature reviews, this paper aims to quantify and characterise important invasion parameters, such as pathways of introduction, time between introduction and detection, lag phase and plasticity of life history traits. Every decade, five new countries have reported P. parva introduction, mainly resulting from the movement of Chinese carps for fish farming. The mean detection period after first introduction was 4 years, a duration insufficient to prevent their pan‐continental invasion. High phenotypic plasticity in fitness related traits such as growth, early maturity, fecundity, reproductive behaviour and the ability to cope with novel pathogens has predisposed P. parva to being a strong invader. The Pseudorasbora parva invasion has provided quantitative data for the development of 1) early warning systems across different spatial scales; 2) rapid eradication programmes prior to natural spread in open systems and 3) sound risk assessments with emphasis on plasticity of life history traits.     

滇池鲤4种年龄鉴定材料的比较

为确定鉴定滇池鲤（Cyprinus carpio）年龄的适宜材料，对4种年龄鉴定材料（耳石、鳞片、胸鳍条和鳃盖骨）的形态和年轮标志进行了描述，并对这4种钙化组织鉴定鲤年龄的一致性进行了探讨。2013年5、6、8-11月以及2014年3-7月，使用拖网采集云南滇池鲤584尾，体长范围7.5~50.5 cm，体重范围17.2~3 211.3 g。其中耳石采集于584尾样本，鳃盖骨和鳞片分别采集于276尾样本，胸鳍条采集于274尾样本。微耳石磨片轮纹清晰，在反射光下呈明暗相间的条纹，年龄标志明显。同一鉴定者2次年龄读数的吻合率，微耳石磨片轮最高（88.0%)，鳞片次之(84.1%)，胸鳍条和鳃盖骨则分别为73.7%和72.1%。2次读龄的平均误差百分比，微耳石磨片和鳞片较小，分别为2.6%和2.9%；胸鳍条和鳃盖骨较高，分别为4.7%和5.9%。以微耳石磨片年龄读数为基准，鳞片年龄读数与其吻合率最高(77.5%)，平均变异系数最低(6.14%)；鳃盖骨和胸鳍条与其吻合率分别为61.9%和56.2%，平均变异系数均超过12%。综合分析认为，耳石是滇池鲤年龄鉴定的最佳材料，鉴定4龄以下个体年龄时可使用鳞片，鳃盖骨和胸鳍条则不适于滇池鲤的年龄鉴定。     

南极鱼类年龄与生长研究进展

南极鱼类生长相对缓慢,独特的生物学特性使其年龄鉴定较其他海区鱼类更为困难。但考虑到鱼类年龄鉴定是开展渔业资源评估的基础,因此过去一些年来,硬质部位,如鳞片、鳍条(棘)、脊椎骨以及耳石等仍成为南极鱼类的主要鉴龄材料。本文对南极鱼类年龄鉴定的方法和材料进行了总结回顾,将年龄鉴定的方法和材料进行比较,分析各自优缺点。结果显示:(1)对于具鳞的南极鱼类,因鳞片在鱼类生长过程中存在重吸收现象,因而利用鳞片及鳍条(棘)单独鉴龄所得出的结果通常小于耳石的鉴龄结果,缺乏精确性;(2)南极鱼类生活跨度较大,高龄鱼体长频次分布严重重叠,以致无法准确判断其年龄结构;(3)耳石重量法易受到特殊个体影响而误判年龄;(4)因鳍条易损坏,脊椎骨采集较为困难,且许多南极鱼类无鳞,目前大多数南极鱼类使用耳石鉴定年龄,其也成为目前最为精准的南极鱼类鉴龄方法,但同时利用鳞片和耳石重量等对鉴定结果进行验证;(5)南极鱼类尚存在无统一的鉴龄标准、人为主观性较强以及缺乏早期生活史研究等不足之处;(6)为了研究南极鱼类早期生活史,耳石微化学及微结构等方法将被广泛利用。     

黄渤海常见鱼类鳞片的形态特征

本研究选取黄渤海28种常见鱼类为研究对象,描述不同部位鱼鳞的形态特征。结果显示,鲱形目鱼鳞鳞焦不明显,辐射沟呈横向或波纹状分布;鳕形目鱼鳞密布小方块状特殊结构;灯笼鱼目鱼鳞辐射沟数目少;鲈形目和鲉形目鱼鳞呈卵圆形或矩形,前区边缘有不规则钝齿结构;鲽形目鱼鳞前区辐射沟多而密集。不同科属鱼鳞在形状、鳞焦位置、环片形状、辐射沟特征、栉齿分布和侧线管形状等形态特征上有明显差异,可用于不同分类阶元的鉴定。本研究构建的鱼鳞形态信息库为鱼鳞沉积信息分析等基于鱼鳞形态的种类鉴别提供了基础资料。     

Eradicating the invasive topmouth gudgeon, Pseudorasbora parva, from a recreational fishery in northern England

Abstract  An established population of the invasive topmouth gudgeon, Pseudorasbora parva (Temminck & Schlegel), was discovered in a recreational fishery in Northwest England in 2002. As the lake was seasonally connected to a river catchment, providing potential for dispersal, a containment and eradication programme was initiated. Containment involved screening of outfalls and preventing fish movements off site. Eradication involved the fishery being treated twice with a rotenone-based piscicide, in March and April 2005. The mean P. parva density prior to rotenone application was 6.1 m⁻²; following the application, none were recorded. Non-target species in the fishery were removed prior to the application; following rotenone degradation, they were re-introduced and subsequently spawned, with recording of young-of-the-year. This contrasts with 2004 when only young-of-the-year of P. parva were recorded. As the eradication appeared to be successful, the method is considered suitable for use on other populations posing a similar threat of dispersal of the species into rivers and on other invasive fish populations in undesirable locations.     

Comparison of pelvic fin rays, scales and otoliths for estimating age and growth of bull trout, Salvelinus confluentus

Abstract  The suitability of three anatomical structures to determine age and growth of bull trout, Salvelinus confluentus (Suckley), was assessed. Scales and pelvic fin rays collected from recaptured bull trout 96–265 mm TL were used to validate annulus formation and assess the accuracy and precision of back calculation. Ageing precision and agreement of assigned ages were compared among scales, fin rays and otoliths from bull trout 52–711 mm TL. Annulus formation was validated for 88% (14 of 16 fish) of recaptured bull trout using pelvic fin rays and 68% using scales (15 of 22 fish). Annulus formation in fin rays occurred between late April to early June, and the hyaline (non-growth) band began forming in late August. Back-calculated length was not significantly different from measured length at initial capture either for fin rays or scales ( P  ≥   0.19), and absolute percent error was 7.2 ± 1.2 (mean ± SE; n  =   14) for fin rays and 8.7 ± 1.9 ( n  =   15) for scales. Consistency of back-calculated lengths at age between tag and recapture samples for individual fish was similar for fin rays (mean absolute difference = 8.2% ± 0.9; n  =   33) and scales (9.4% ± 1.4; n  =   40). However, fin rays (87% precision) and otoliths (90%) provided notably higher ageing precision than scales (68%) and closer agreement of assigned ages, particularly for fish older than age 4. Pelvic fin rays appear to offer more accurate and precise age and growth determinations than scales and a non-lethal alternative to otoliths, but further work is needed to validate the accuracy and precision of ageing large, migratory bull trout.     

Eradication of the invasive Pseudorasbora parva results in increased growth and production of native fishes

Abstract –  The topmouth gudgeon, Pseudorasbora parva , has been described as Europe's most invasive fish. To control their UK invasion, some lentic populations at risk of causing fluvial dispersal have been eradicated. The first of these operations was from a lake in north-west UK in March 2005 using rotenone application; prior to eradication, their mean density was estimated as 6.1 m⁻² whereas since eradication, no P . parva have been recorded. Prior to rotenone application, the majority of native fishes were removed, held off-site and reintroduced following degradation of rotenone to safe levels. In the three growth seasons since their reintroduction and P . parva eradication, the abundance, somatic growth rate and production of roach Rutilus rutilus and common bream Abramis brama have increased significantly; production is now driven by a lower number of comparatively larger, faster growing individuals. These data suggest that the eradication of this P . parva population has been highly beneficial for the growth, recruitment and production of these native species.     

梯级开发下金沙江下游鱼类群落结构特征及环境驱动因子

为了探明梯级电站开发下金沙江下游鱼类群落的结构特征及主要环境驱动因子，于2017年对春季和秋季金沙江下游尚未建成的乌东德和白鹤滩水电站江段以及已下闸蓄水的溪洛渡和向家坝水电站江段应用多网目复合刺网进行了鱼类群落定量研究，同时运用多种统计分析方法分析了鱼类多样性特征以及鱼类群落与环境因子的关系。研究发现仍保持正常流水未成库区的乌东德和白鹤滩江段鱼类群落与已成库区的溪洛渡和向家坝江段有着明显的差异。在仍为峡谷激流型生境的江段，鱼类组成以土著特有鱼类为主，优势种为喜流水的圆口铜鱼C. guichenoti、泉水鱼P. procheilus、犁头鳅L. fimbriata；而在已蓄水的库区江段，鱼类组成多为长江中下游常见种类，优势种为喜静水缓流的?H. leucisculus、飘鱼P. sinensis、似鱎T. wwinhonis。应用典范对应分析对鱼类群落与环境因子做了相关分析，发现影响金沙江下游鱼类群落的主要环境驱动因子包括水深、总固体悬浮物、电导率、pH和水温等。这些研究结果为制定金沙江下游鱼类种质资源和生物多样性保护的相关管理政策提供了基础与支撑。     

麦穗鱼鳍条组织培养及染色体Ag—NORs和C-带研究

采用组织块贴壁培养法，探索了麦穗鱼（Pseudorasbora parva）鳍组织细胞短期培养方法，同时对其染色体Ag-NORs和C-带进行了初步研究。结果显示：1）麦穗鱼鳍组织培养的最适培养基为MEM培养基，细胞在组织块贴壁后第6天迁出，经传代后细胞形态呈成纤维状；2）其染色体具有1对Ag-NORs，位于第23对染色体短臂末端，其NORs具多态性，未见Ag-NORs联合现象；3）其染色体C-带主要为端粒和着丝点C-带，少数为居间C-带，其中第23对染色体的短臂大部分呈现C-带强阳性，与Ag-NORs区域对应。     

尼罗尖吻鲈(Lates niloticus L.)的形态和生物学特性

解剖观察自埃及引进的尼罗尖吻鲈(Lates niloticus L.),对其形态特征做了详细记录,并在养殖过程中对生物学特性做了观察。尼罗尖吻鲈体延长,侧扁;DⅦ~Ⅷ,10~14。前鳃盖下缘有强棘;鳃盖后缘呈锯齿状,有一硬棘。被鳞为栉鳞,中等大小,侧线清晰与体背缘平行,具侧线鳞60~80枚。尾鳍圆滑不分叉。成鱼鱼体银白色,并有暗色条纹,幼鱼背部大多有青黑色斑块,下半部银色。消化道粗短,与体长之比约为0.66。尼罗尖吻鲈是热带种类,肉食性,适宜生长温度为26~32℃,生长速度快,一般2~3年性成熟。