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人工诱导泥鳅雌核发育试验 总被引：1，自引：0，他引：1
《江西水产科技》2017,(1)
用经UV灭活的野鲤精子激活泥鳅卵,以冷休克与热休克二种方式诱导激活卵的染色体加倍。冷休克组进行休克起始时间、持续时间二参数组合试验,休克起始时间分别为3min、4min、5min,持续时间为20min、25min,休克处理温度0℃-3℃。热休克组休克起始时间为3min35s,持续时间为2min,休克处理温度为39℃-41℃。结果:冷休克组各组合均得到雌核发育二倍体泥鳅苗,以休克起始时间为3min、持续时间为25min组合雌核发育二倍体的诱导率最高,达28.8%-34.1%。热休克组雌核发育二倍体诱导率52.1%-56.3%,与冷休克各组合间均存在极显著差异(P0.01),诱导效果显著好于冷休克组。泥鳅苗经12d培育,冷休克组成活率28.6%,全长0.7-1.6cm;热休克组成活率43%,全长0.5-1.4cm;对照组成活率70.5%,规格与冷休克组相当。 相似文献
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长丰鲢系1987年从长江鲢性成熟个体中,选择个体大、体型好的雌鱼为母本,用遗传灭活的鲤精子做激活源,采用极体雌核发育方法,经连续两代异源雌核发育、两代群体选育,获得的选育鲢F4。2009年12月22日我们从中国水产科学研究院长江水产研究所引进1龄长丰鲢200尾,作为后备亲本,经过3年精心培育,2011年有部分亲鱼成熟进行了人工繁殖,今年全部亲鱼进行了繁殖。现将长丰鲢亲本培育及人工繁殖过程介绍如下: 相似文献
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黄姑鱼雌核发育诱导及鉴定 总被引：2，自引：0，他引：2
为建立黄姑鱼雌核发育诱导方法,实验利用紫外线照射使黄姑鱼精子遗传失活,与卵子授精后再通过冷休克抑制极体排放进行倍性恢复,成功诱导出黄姑鱼雌核发育二倍体。精子经强度为3 800μW/(cm2·s)的紫外线照射10～100 s,受精卵孵化率呈现明显的Hertwig效应;当照射时长达到60 s以上,各实验组全部孵出仔鱼均呈现单倍体综合症。精子的紫外线照射时间、受精卵冷休克起始和持续时间等三因素三水平正交实验结果表明,精子经紫外线照射60 s,受精2 min后卵子在3～4 ℃海水中持续冷休克10 min为最佳诱导条件组合,可以获得最高的孵化率(16%)。最佳组合仔鱼形态和细胞相对DNA含量与正常二倍体一致,经微卫星标记检验证明全部不含有父本基因,为雌核发育二倍体。实验报道了成功诱导黄姑鱼雌核发育二倍体的条件,为进一步开展黄姑鱼良种选育和性别控制工作奠定了基础。 相似文献
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为获得团头鲂(Megalobrama amblycephala)的纯合品系, 本研究以团头鲂“浦江 2 号”作为亲本, 采用紫外线灭活的鲤鱼精子刺激团头鲂卵子, 经冷休克抑制第二极体排出的方法获得异源雌核发育一代群体(Meio-G1)和雌核发育二代群体(Meio-G2)。利用筛选出的 20 对微卫星引物, 研究分析了团头鲂“浦江 2 号”正常群体、雌核发育一代群体(Meio-G1)和雌核发育二代群体(Meio-G2)的遗传特征。结果表明, 正常群体、Meio-G1 和 Meio-G2 中, 分别扩增出 129、99、84 个等位基因, 平均等位基因数(Na)分别为 4.30、3.30、2.80, 平均有效等位基因数(Ne)分别为 3.23、 2.24、1.76, 平均观测杂合度(Ho)分别为 0.8067、0.4067、0.1733, 平均纯合度(H)分别为 0.2035、0.6000、0.8263, 平均多态信息含量(PIC)分别为 0.6198、0.4701、0.3628, 表明 Meio-G1 和 Meio-G2 相较于正常群体其遗传多样性下降, 其中 Meio-G2 的遗传多样性最小。Hardy-Weinberg 平衡遗传偏离指数表明 Meio-G1 和 Meio-G2 出现杂合子缺失的现象, 而正常群体则表现为杂合子过剩。聚类分析显示, 正常群体与 Meio-G1 共同汇聚成为一支, 而 Meio-G2 单独成为一支, 产生了一定程度的遗传分化。本研究结果表明, Meio-G2 的纯合度高、遗传多样性低, 是良好的育种材料, 可为团头鲂的选育工作提供重要参考依据。 相似文献
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为了构建团头鲂耐低氧新品种,实验从鄱阳湖引进和挑选野生优良亲本为奠基群体F0,2009年–2011年通过群体选育获得F1,2011年再通过群体选育实现了F1到F2的传代。2012年,以鄱阳湖选育F2亲本和团头鲂"浦江1号"F9亲本为基础,经夏、秋季2次低氧胁迫,筛选出536尾耐低氧能力强的F2亲本,构成团头鲂耐低氧F2。2013年,挑选个体大、体形好的F2亲本(雌鱼50尾、雄鱼48尾)建立了24个F3家系群体(2♀×2♂群体22个、3♀×2♂群体2个),共100个F3家系。对上述F3家系群体进行1龄阶段的低氧胁迫养殖,通过测定相应生长指标和耐低氧性状,共筛选出5个快速生长家系群体(A2、A3、A18、A19和A20)和6个生长较快的家系群体(A4、A6、A17、A25、A27、A28),微卫星分析其分别归属于20个和28个家系。结果显示,团头鲂的生长性能指标与耐低氧性状呈正相关。在1龄阶段长时间低氧胁迫养殖条件下,团头鲂耐低氧F3中耐低氧能力强的家系的体质量显著大于耐低氧能力弱的家系,选育出的团头鲂耐低氧F3家系在2龄阶段同样保持了快速生长特征。本研究旨在建立团头鲂耐低氧F3新品系,以供后续团头鲂耐低氧新品种的选育。 相似文献
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青岛文昌鱼遗传多样性的RAPD分析 总被引：11，自引：0，他引：11
采用RAPD技术对青岛文昌鱼雌、雄各11条个体共22个样本进行遗传多样性检测。从40个寡聚核苷酸随机引物中筛选出17个扩增重复性好、条带清晰、特异性强的引物,对每个个体基因组DNA进行了扩增。得到RAPD产物的分子量在200～2200bp之间,产物总计127个位点,其中,多态位点60个(占47．24％)。计算个体间遗传相似系数平均为0．8656,个体间遗传距离平均为0．1344。用Shannon多样性指数量化的遗传多态度(Ho),雄性群体(0．1912)高于雌性群体(0．1125),平均遗传多态度(Hpop)为0．1519。文昌鱼遗传多态度所占的比例在群体内为0．2553,而雌、雄群体间为0．7447。在文昌鱼雌、雄个体RAPD产物中,两个电泳图谱上能读出明显的雄性特征带,估计可能与雄性文昌鱼具有异型性染色体有关,这与XY型性别决定机制相吻合。引物OPC12扩增产物250bp为雄性文昌鱼所特有,可能为区别性别的分子标记。用NJ法进行聚类分析,结果表明,22个个体明显按性剐聚成两类,文昌鱼雌、雄个体基因组间的差异较大。 相似文献
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采用AFLP技术对大口黑鲈(Micropterus salmoides)F3、F4代选育群体的遗传结构进行分析,并计算2个选育群体和一个对照养殖群体的遗传多态度、遗传距离及分化系数。结果显示,8对AFLP引物共扩增到262条带,其中多态性条带有80条,每对引物检测到的多态性条带在5～13之间。F3、F4代选育群体和对照养殖群体的多态性位点比例分别为29.36%、29.20%、30.29%。Shannon多样性指数分别为0.2017,0.1955,0.2042。结果表明,选育群体相较于对照养殖群体多态位点比例和遗传多态度均有所下降。群体间的遗传变异平均为0.0752,由此可见,92.48%的遗传变异来自于群体内,而只有7.52%的遗传变异来自于群体间,这初步显示了大口黑鲈在遗传上的稳定性,群体尚具有一定的选育潜力,可继续进行人工选育。 相似文献
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为进一步验证团头鲂配套系间杂交子代的生长优势,以团头鲂"浦江1号"选育系F_(12)为对照组,通过开展同池养殖试验,分析了优势配套组合(优势组)——雌核发育群体F_4(♀)×"浦江1号"F_(11)(♂)子代在1龄至2龄阶段的生长性能。结果显示:在1龄阶段,优势组试验鱼的终末体质量比对照组高12.54%(P0.05),特定增重率比对照组高2.47%(P0.05);在2龄阶段,优势组试验鱼的相对增重率比对照组高8.97%(P0.05),特定增重率比对照组高4.62%(P0.05)。优势组在1龄和2龄阶段的体质量变异系数均低于对照组(P0.05)。与对照组相比,优势组在1龄阶段成活率略低,而在2龄阶段成活率略高(P0.05)。结果表明,团头鲂优势配套系在1龄和2龄阶段有明显的生长优势,但在整齐度和成活率方面与团头鲂"浦江1号"选育系F_(12)没有显著差异。 相似文献
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在流水池饲养环境里，对吉富品系尼罗罗非选育系F6、F7、F8三代鱼二龄鱼按雌、雄分组后进行生长性能比较。经过123d的饲养，F6、F7、F8二龄鱼雌鱼绝对增重率为3．13g／d、3．16g／d、3．19g／d，相应特定增重率为0．66％／d、0．68％／d、0．67％／d；F6、F7、F8二龄鱼雄鱼绝对增重率为3．27g／d、3．31g／d、3．39g／d，相应特定增重率为0．55％／d、0．56％／d、0．57％／d。F6、F7、F8二龄鱼的增重率基本呈现出逐代增大的趋势，但增大的程度比较微弱。不同阶段F6、F7、F8代二龄雌、雄鱼的特定增重率随着饲养天数的增加均呈现出下降的趋势。 相似文献
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Measuring and interpreting genetic structure to minimize the genetic risks of translocations 总被引：3，自引：0，他引：3
M S. Johnson 《Aquaculture Research》2000,31(1):133-143
Genetic subdivision of a species indicates the potential for local adaptation, and the genetic differences among populations are a key component of genetic diversity. Molecular genetic markers are generally used to assess the extent and pattern of subdivision. These traits provide an abundance of simple genetic markers, and they allow comparisons across studies. However, the connection of molecular genetic variation to local adaptation and, hence, to possible genetic problems of translocation, is weak. In the extreme case of no genetic subdivision, there is no reason to expect genetic problems with translocation. Where there is deep genetic structure, indicating substantial evolutionary independence of sets of populations, translocations may threaten basic components of genetic diversity. Between these extremes, however, predicting genetic problems of translocations is extremely difficult. The molecular markers used to measure genetic structure indicate where there has been opportunity for local adaptation, but they are not directly related to such adaptation. The relationship of the level of genetic divergence to genetic incompatibilities is very loose, although quantitative tests are scarce. However, studies of reproductive isolation between species illustrate the fundamental inadequacy of using measures of genetic divergence to predict interactions between populations. Although it is tempting to use simple measures as predictors, such use may provide a false sense of scientific rigour. There is no substitute for direct tests for variation in ecologically relevant traits and possible genetic incompatibilities among populations. 相似文献
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Genetic improvement of aquaculture species offers a substantial opportunity for increased production efficiency, health, product quality and, ultimately, profitability in aquacultural enterprises. Technolo‐gies exist that can be implemented immediately to improve multiple traits that have economic value, while simultaneously accounting for inbreeding effects. Genetic improvement techniques for delivering genetic gain include formal definition of the breeding objective, estimation of genetic parameters that describe populations and their differences, evaluation of additive and non‐additive genetic merit of individuals or families and defining the structure of a breeding programme in terms of mating plans. Novel genetic technologies involving the use of DNA‐based tools are also under development for a range of aquaculture species. These gene marker technologies can be used for identification and monitoring of lines, families and individuals, monitoring and control of inbreeding, diagnosis of simply inherited traits and genetic improvement through selection for favourable genes and gene combinations. The identification of quantitative trait loci (QTL), and direct or linked markers for them, will facilitate marker‐assisted selection in aquaculture species, enabling improvement in economically important traits, particularly those that are difficult to breed for, such as food conversion efficiency and disease resistance. 相似文献
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J. MORK 《Aquaculture Research》1994,25(Z2):93-98
The differentiation process in a set of idealized populations is simulated by computer programs. Absolute and relative effects of genetic drift, gene flow (through straying) and natural selection on the genetic population structure are explored. The effect of increased gene flow in an equilibrium situation is studied for both neutral and selected traits. 相似文献
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伴随着中国水产养殖业的快速发展,原产美国的旧金山卤虫(Artemia franciscana)被引入至我国渤海湾地区.为研究旧金山卤虫被引入中国后其基因组遗传多样性改变情况,本研究利用COI线粒体分子标记,评估旧金山卤虫在非原生栖息地,即唐山曹妃甸南堡镇(渤海湾,河北省)定殖的旧金山卤虫的遗传多样性现状.研究分析发现:... 相似文献
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采用聚丙烯酰胺不连续凝胶垂直板电泳技术对三疣梭子蟹的同工酶进行检测。分析了13种同工酶在莱州湾三疣梭子蟹肌肉中的表达情况,并对同工酶的表型进行了生化遗传分析。结果表明,13种同工酶有22个基因位点编码,其中Ldh-1,Me-3,Gdh-1,Sdh-1,G6pd-1和Sod-3共6个位点是多态的,多态位点百分数是27.3%。三疣梭子蟹的平均每个位点的等位基因的有效数目Ae为1.2270,平均每个位点的预期杂合度He为0.1170,实际杂合度Ho为0.2159。同时还分析了三疣梭子蟹的各个多态位点的Hardy-Weinberg偏离指数:Ldh-1、Me-3和Sod-3的d值都为1.0000,Gdh-1、Sdh-1和G6pd-1的d值分别为0.5047、0.8726和0.0597。这些数据表明,莱州湾三疣梭子蟹的种质资源还处于较好的状态。 相似文献
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Population genetic structure in penaeid prawns 总被引：14，自引：0，他引：14
J A H. Benzie 《Aquaculture Research》2000,31(1):95-119
Genetic data are available for 27 species of penaeid prawn. Collected largely for fisheries purposes, they include information on several species of importance to aquaculture. Most studies used allozymes, but a small number have used mtDNA, random amplified polymorphic DNAs (RAPDs) and/or microsatellites. The DNA‐based markers have revealed far greater levels of variation compared with the allozyme data. However, in the few cases for which joint information is available, the mtDNA and microsatellite information tended to confirm the spatial patterns of variation detected by allozymes. These revealed little genetic variation over long distances (thousands of kilometres) for many species, but relatively major shifts in gene, or genotype, frequencies over relatively short distances (hundreds of kilometres). Much of the genetic structure in wild populations appears to reflect historical events on large biogeographical scales, rather than resulting from patterns of present‐day dispersal. Genetic variation in cultured stocks is generally less than in wild ones, the extent of the reduction being dependent upon broodstock management procedures. There is no conclusive evidence that aquaculture escapees have altered the genetic constitution of wild stocks of Penaeus monodon in Thailand. Nevertheless, the occurrence of strong patterns of geographic variation in wild stocks suggests that more detailed planning will be required to maintain this diversity, and to determine how best to capture its benefits for aquaculture. 相似文献
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Trygve Gjedrem 《Aquaculture (Amsterdam, Netherlands)》1975,6(1):23-29
A review of the literature concerning phenotypic and genetic parameters for economic production traits in salmonids show that very few estimates are available. However, based on the present knowledge the possibilities for genetic gain in, for example, growth rate are extremely good even if conservative estimates are considered. The high genetic gain may be obtained primarily because of high fertility, a large phenotypic variance and a moderate length of the generation interval. There is a great need to start selection in order to get a more productive animal which is better adapted to captivity. 相似文献
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2001年10月于黑龙江中游抚远江段捕获野生乌苏里白鲑(Coregonus ussuriensis Berg)30尾，体长30-45cm。采用淀粉凝胶电泳法对其肝脏、肌肉等组织的LDH、MDH、ME、IDH、G3PDH、ADH、GDH、PGI、CAT、AAT、EST、SOD等同工酶进行电泳，并对其表型进行生化遗传分析。结果表明，LDH同工酶的3个位点上都有基因复制，位点间不杂合；在其他同工酶上未见有位点复制或加倍。在检测到的12种同工酶是由26个基因位点编码；其中G3pdh-1、Pgi—3和Est—1等基因位点呈多态，其多态座位比例为11．5％，平均杂合度为0．043。与大多数其他鱼类相比较，乌苏里白鲑在生化遗传水平上表现出较低的遗传变异。 相似文献