共查询到18条相似文献，搜索用时 421 毫秒
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约10000余尾注射牛和羊生长激素基因的鲤鱼已被生产出来，并从中筛选出生长速度快且整合了外源基因的个体143尾，也证明外源基因可传递给子代同时子代也具有快速生长的特征。建立了把外源基因直接注入受精卵的方法，确定了注入外源基因的最佳时期。 相似文献
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转生长激素基因鲤鱼的生长研究 总被引：1，自引：1，他引：1
本报导了生长激素基因对鲤鱼生长的影响。经池塘对照实验表明，转生长激素基因鲤鱼的快速生长效应比正常鲤鱼明显，而且由转生长激素基因阳性性成熟鲤鱼经人工催产繁殖的子一代群体中，仍表现出快速生长的特性。这一结果，为能获得一个转外源生长激素基因并具快速生长特性的遗传稳定的转基固鲤鱼核心群体提供了可靠的数据。 相似文献
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从1985年以来,世界各国先后应用不同外源基因导入虹鳟鱼、鲤鱼、鲶鱼等有经济价值的养殖鱼类。但受精卵发育到何时注基因源射外获得高的成活率(孵化率)和整合率一直是研究人员所关心的问题。法国的Chourout等在1986年就做了虹鳟鱼受精卵不同发育时期注射外源基因与孵化率关系实验。美国的Thoms.T.then等人也做了鲤鱼等受精卵在不同发育时期注射外源基因对其成活率、整合率影响的研究。由于外源基因对受体鱼的整合机理比较复杂,不仅这方面的研究不多,而且各实验室之间的研究结果也很不一致,因此至今对某种鱼类的受精印发育到何时是注射外源基因的最佳时期还没有形成一致的意见。本研究以鲤鱼受精卵为材料,通过显微注射技术,在受精卵的不同发育时期把鲤鱼MT启动因子基因,大麻哈鱼CH基因的融合基因导入受精卵中,按孵出的鱼苗数分别计算成活率,再通过斑点杂交和Southern Blot杂交检查整合情况,计算整合率,以探索外源基因导入鲤鱼受精卵的最佳时期。 相似文献
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鲤鱼受精卵导入外源基因最佳时期的研究 总被引：1，自引：0，他引：1
鲤鱼受精卵导入外源基因最佳时期的研究梁利群，孙孝文，沈俊宝，闫学春，王鹏（中国水产科学研究院黑龙江水产研究所，哈尔滨１５００７６）１９８５年以来，世界各国先后应用不同外源基因导入虹鳟鱼、鲤鱼、鲶鱼等人工养殖鱼类以提高鱼的质量和产量。但受精卵发育到何时... 相似文献
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转基因鱼研究及商品化展望 总被引：2，自引：0，他引：2
目前,转基因技术是农业和医药行业的研究热门。自1985年,世界上第一批转基因鱼诞生后,鱼类基因转移技术很快应用到培育高产、优质和抗逆的经济鱼类新品种,并在解决分子生物学、发育生物学和基因转移等方面的难题中发挥着重要作用。近几年,“全鱼”生长激素（GH）基因的克隆与应用,使快速生长转GH基因鱼的研究取得了突破性进展,但仍需要解决转移基因的定位整合、稳定表达和遗传,以及转基因鱼释放的生态和食品安全性等问题。 相似文献
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转生长激素基因鲤的快速生长效应及传代 总被引：3，自引：0，他引：3
报道了转生长激素基因鲤阳性群体的建立科“超级鲤”的获得。给出了“超级鲤”和对照组连续4年的生长实验结果及“超级鲤”子代连续3年的生长对照的体重数据。结果显示,外源生长激素基因对受体鲤具有快速生长效应,但具有这种超速生长作用的个体在转基因鲤群体中占极少数。此效应能传递给子代,子代中快速生长个体的比例大大高于转基因实验群体。 相似文献
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海水比重、温度和底质对青蛤稚贝生长、存活的影响 总被引：7，自引：1，他引：7
本文阐述了海水比重、温度和底质对青蛤稚贝生长和存活率的影响。青蛤稚贝在1.010～1.025比重范围内,生活正常,比重越高,生长越快;超过1.025,比重越高,生长变慢,存活率降低。青蛤适宜生长和存活的温度范围为10～33℃,在此范围内,温度越高,生长越快,存活率也就越高;超过33℃时,生长变慢,存活率降低。青蛤稚贝适宜底质为砂质和细砂质,纯泥质不适青蛤稚贝生长。 相似文献
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Mushtaq Ahmad Klasra Halil Fidan 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):317-330
ABSTRACT The purpose of this study is to examine whether and to what extent the shares of selected countries' fishery exports in the world markets reflect their international competitiveness. The Constant Market Share (CMS) model, which decomposes export growth into some broad components (i.e., structural effects, market effects, commodity effects and competitive effects), is applied to examine this issue. The results of decomposition analysis revealed that structural factors have been more significant in explaining the growth of exports. The growth effects, though, appeared positive for each country, the exports of open economies like Canada, the United States, Iceland and Turkey benefited more from the growth of world exports. The analysis of commodity composition and market effects suggests that countries like Canada, the United States, Iceland and Turkey were pursuing the product differentiation policy and were penetrating in those markets, which have been growing relatively faster. These countries remained committed throughout the sample period (i.e., 1980–2000) to export their diversified products in fast-growing markets. The analysis of competitiveness effects, which are derived as a residual, show that Norway, Spain, the United States, Indonesia, Thailand, Chile and China were strong fishery exporters and increased their competitiveness during the sample period. 相似文献
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Sox(SRY-related HMG-box)基因家族是在动物体内发现的一类编码转录因子的基因家族,广泛参与了动物生长发育、理化反应,特别是性别决定和分化等过程.本研究采用生物信息学方法,利用Sox基因高度保守的HMG-box区序列作为种子序列,检索半滑舌鳎(Cynoglossus semilaevis)基因组注释的蛋白数据库,共鉴定分离出23个Sox基因.并在全基因组水平对半滑舌鳎Sox基因家族进行了保守结构域序列、进化、基因结构、染色体定位及基因表达模式的系统分析.结果显示,通过保守结构域分析发现了半滑舌鳎Sox基因家族除CseSox32外,皆存在一段9个氨基酸残基(RPMNAFMVW)的高度保守基序;结合保守结构域及进化分析,所有半滑舌鳎Sox基因被分为B1、B2、C、D、E、F和K共7个亚族,且不同的亚族在进化上存在种间趋同性和种内特异性;基因结构分析将半滑舌鳎Sox基因分为两大类,即单外显子类和多外显子类;而染色体定位分析则显示,Sox基因在染色体上散乱分布,不存在集簇现象;不同类型性腺及幼鱼变态前后的Sox基因家族表达谱显示,半滑舌鳎Sox基因具有不同的组织表达模式,表明其在性别分化、性腺发育及早期幼鱼发育过程中可能发挥了重要作用.本研究对于今后半滑舌鳎Sox基因家族深入的功能验证及分子作用机制研究具有重要的意义,也为日益丰富的水产基因组资源的挖掘利用提供了参考. 相似文献
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鲍遗传育种研究进展 总被引：5，自引：0，他引：5
Abalones are important farming species with a high economic value. They have already been farmed for more than 50 years. As problems and new requirements rose continuously in culture industry of abalone, studies on genetic and breeding techniques are needed to improve characteristics and to gain new traits. This review concentrates on advances in genetics and breeding techniques in abalone. As for genetic studies, karyological analyses, allozyme, DNA markers and genetic diversity were reviewed. So far, karyological analyses in abalone have been performed in 12 species that can be divided into three groups according to the chromosome number. In some economically important species, loci of allozymes and. microsatellites have been isolated and applied to investigate the genetic structure of natural and hatchery populations and to identify the result of chromosome set manipulation, but the related reports are only a few yet. The resultsof investigation with DNA markers and allozymes showed that the genetic structure of natural populations presents two characteristics: excessive homozygosity and subdivision. Advances of various breeding techniques, including introduction, selection,hybridization, polyploidy, gynogenesis and gene manipulation, were reviewed in the other part. Although Haliotis discus discus, introduced from Japan, has become one of the most important culture species in China, the economic, social and environmental effects of introduction have been rarely studied. Selection is one of the most important and basic breeding techniques, but the studies on selection are only a few and preliminary, referring to the relations between genetic characteristics and the traits of growth and resistance, genetic diversity and heritability of quantitative traits, and the effect of selection. Interspecific hybridization was the first breeding program carded out in abalone. Experimental hybridization have been carded out for about 20 crosses. Heterosis,such as faster growth and high survival rate, has been observed in some crosses. Triploids have been successfully induced in many species of abalone with physical or chemical shock, e.g.H, discus hannai, H. rufescens, H.diversicolor diversicolor and H. rnidae. Field experiments were conducted in some species of triploid abalone. In comparison with triploid, the research on tetraploid is still in quest stage. The progress of induction of gynogenesis in abalone is quite slow. Conditions of sperm inactivation, diploid restoration and nuclear behavior of gynogenetically activated eggs have been researched on in H. discus han nai. Notwithstanding the gene transfer technology in abalone is in the quest stage, the research have already involved preparation of exogenic DNA,means of gene transfer, identification integration and expression of target gene, etc. Three research directions in these topics were proposed : to investigate the germplasm resources of abalone deeply and widely, to make use of traditional breeding methods and modem biotechnique synthetically, and to combine the science research with production practice. 相似文献
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Eradication of the invasive Pseudorasbora parva results in increased growth and production of native fishes 总被引：1，自引：0，他引：1
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. 相似文献