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宁德市大黄鱼产业发展现状和产业升级对策初探 总被引：1，自引：0，他引：1
正大黄鱼是我国海水鱼类中重要的组成部分,也是我国石首鱼类中珍贵的种质资源。人工养殖主要集中在福建,广东、浙江和山东也有少量养殖。2014年我国大黄鱼养殖产量12.79万吨,其中福建11.45万吨,占89.5%,而福建大黄鱼养殖主要集中在宁德市。本文依据实地调研宁德市大黄鱼产业获得的一手材料和前人的资料,对宁德市大黄鱼产业发展的现状与成效进行了简要的分析,以期为大黄鱼产业健康持续发展提供参考。 相似文献
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水产种质资源是渔业捕捞、水产增殖养殖和良种选育的生物基础,是渔业可持续发展的重要物质基础之一,具有较高的经济价值和遗传育种价值.2019年国务院办公厅发布了《关于加强农业种质资源保护与利用的意见》(国办发〔2019〕56号)提出,制定全面的种质资源保护和利用规范,加强水产种质资源保护和利用研究,加快水产种质资源库建设等工作,以切实加强种质资源保护,进一步夯实渔业发展基础.因此,科学化开展水产种质资源保护与利用具有重要意义. 相似文献
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微卫星分析四个大黄鱼群体的遗传多样性 总被引：3，自引：1，他引：2
为保护人工养殖大黄鱼的种质资源,用15对微卫星标记对来自浙江沿海地区的四个大黄鱼养殖群体共171个个体进行了遗传多样性分析.结果显示,这些标记在四个群体中均表现出丰富的多态性;共检测到206个等位基因;各基因座观测等位基因数7～23个,平均等位基因数13.73,大小在88～318bp之间.四个群体的平均观测杂和度(Ho)为0.5981～0.6893,期望杂和度(He)为0.7319～0.7944,多态信息含量(PIC)0.7138～0.7836,表明四个养殖群体在所检测位点均具有较好的多态性.对遗传距离的计算结果表明闵粤东群体与反交群体较近,聚类结果中首先聚到一起.本研究首次选择微卫星标记评估人共选育大黄鱼群体的遗传多样性,并采用高精度的377 DNA测序仪进行检测,将对大黄鱼的种质资源保护提供科学依据. 相似文献
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水生生物种质资源是生物种质资源的重要组成部分,它是水产育种、养殖生产和渔业科技发展的重要物质基础,也是支撑国民生产、人民生活和社会科技活动的重要战略资源,在国际竞争中,日显其重要地位。为加强水产种质资源的保护和利用,促进渔业的可持续发展,我国已将保护水产种质资源写进渔业法》。新修订的《水产苗种管理办法》明确指出国家将有计划地搜集、整理、鉴定、保护、保存和合理利用水产种质资源。可见研究、保护和利用好水产种质资源是我国渔业科技发展的重点之一。在水产种质的保护和利用的工作中,如何加强我国水产种质的检测和监测能力,完善种质检测技术是确保我国水产种质资源的合理利用的重要保障。在种质利用方面水产养殖业与农业一样,优良的品种对于养殖产业的提高起着十分重要的作用,在其它条件一样的情况下,使用良种可增加产量20—30%,是水产养殖业的重要基础。为了进一步推动水产原良种体系建设,国家先后投资建设了一批国家级原良种场和省级原良种场,对优良品种进行遗传改良、提纯复壮。为保护和合理利用水产种质资源,加强水产品种选育苗种生产、经营、进出口管理,提高水产苗种质量,维护水产苗种生产者、经营者和使用者的合法权益,促进水产养殖业持续健康发展,根... 相似文献
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大黄鱼(Pseudosciaena crocea)是一种名贵海水经济鱼类，从上世纪90年初开始大黄鱼在南方地区大规模育苗和养殖。由于没有对大黄鱼实施种质改良，故近几年养殖大黄鱼种质衰退，导致养殖大黄鱼生长速率下降，病害频发、品质下降，直接影响了大黄鱼的经济价值。如何改良养殖大黄鱼的种质，保持大黄鱼养殖业的持续发展，已成为水产养殖研究的重要内容。目前通过染色体工程技术实现鱼类种质改良成为大黄鱼遗传育种的重要途径之一，其中多倍体大黄鱼的诱导技术研究较为热门。 本文就热休克法和冷休克法诱导大黄鱼四倍体的实验进行了总结。 … 相似文献
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近年，由于养殖一哄而上，大黄鱼目前出现大量积压，引起业内人士的关注，并针对这一问题建言献策。 一、从改善大黄鱼种质入手．因势利导建立大黄鱼原良种场 近年养殖的大黄鱼多系福建引进的闽东族，由于多年的养殖，种质已严重退化，不再具有原来的大黄鱼风味。目前舟山已采集岱衢族大黄鱼亲种进行繁育，因势利导建立大黄鱼原良种场，保持水产原良种的优良性状，应是大黄鱼养殖常盛不衰的根本所在。 二、改变投饵结构，多喂配合饲料 该市养殖的大黄鱼投饵多为鲜活饲料，尤以富含脂肪的青占鱼为主，这一方面造成养殖环境污染，另一方面也造… 相似文献
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D. C. Dauwalter 《Fisheries Management and Ecology》2013,20(4):289-301
Energy development threatens fish and wildlife resources worldwide. This study used constrained ordinations to show fish assemblage structure associated with oil and gas well densities in the Colorado River Basin, Wyoming, but well densities explained only 6.4% of assemblage structure when compared to other factors. Threshold Indicator Taxonomic ANalysis showed significant negative threshold responses by some species to small levels of development (<0.15 wells km?2), whereas positive thresholds were less distinct. Some native and imperilled species could be disproportionately affected if future oil and gas development proceeds in a manner that will impact aquatic resources. Although existing development has not substantially influenced regional fish assemblage structure, it appears to affect a subset of species. Understanding assemblage‐level responses to development can help land managers determine appropriate development levels, prioritise areas for monitoring associated with future development and identify where land protection measures may be needed to offset potential risks. 相似文献
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Claude E. Boyd Louis R. D'Abramo Brent D. Glencross David C. Huyben Lorenzo M. Juarez George S. Lockwood Aaron A. McNevin Albert G. J. Tacon Fabrice Teletchea Joseph R. Tomasso Jr Craig S. Tucker Wagner C. Valenti 《Journal of the World Aquaculture Society》2020,51(3):578-633
Important operational changes that have gradually been assimilated and new approaches that are developing as part of the movement toward sustainable intensive aquaculture production systems are presented via historical, current, and future perspectives. Improved environmental and economic sustainability based on increased efficiency of production continues to be realized. As a result, aquaculture continues to reduce its carbon footprint through reduced greenhouse gas emissions. Reduced use of freshwater and land resources per unit of production, improved feed management practices as well as increased knowledge of nutrient requirements, effective feed ingredients and additives, domestication of species, and new farming practices are now being applied or evaluated. Successful expansion into culture of marine species, both off and on shore, offers the potential of substantial increases in sustainable intensive aquaculture production combined with integrative efforts to increase efficiency will principally contribute to satisfying the increasing global demand for protein and food security needs. 相似文献
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A report is presented of esophagoscopy and gastroscopy in cats and dogs using flexible endoscopes. Following consideration of the basic equipment, an account is given of patient preparation and anesthesia, topography, investigation technique and normal findings. Diagnostic potential, indications and risks involved are discussed. 相似文献
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Roberto Mendoza Alfaro Carlos Aguilera González & Allyse M Ferrara 《Aquaculture Research》2008,39(7):748-763
Many lepisosteid populations in North America have declined and many are now threatened as a consequence of habitat loss and alteration and commercial and sport overfishing. Over the last two decades, morphological, histological and molecular studies allowed distinguishing between different phases of development and the nutritional condition of larvae. Ontogeny of the digestive enzymes of gar larvae indicated the possibility to feed them artificial feeds since early developmental stages. An in vitro digestibility system to test different feed ingredients has been used. Important characteristics of artificial diets were identified through different feeding experiments. Endocrinological studies showed the feasibility of altering larval development and the digestive capacity of larvae. Cloning of gar growth hormone opened new avenues to enhance growth in the gars. Plasmatic vitellogenin was isolated and purified, to develop a competitive enzyme‐linked immunosorbent assay, which allowed the straightforward separation of males from females to establish appropriate proportions for reproduction and also was used to evaluate hormonal protocols to induce gonad recrudescence and spawning. This review analyzes the biology, ecology and physiology of different gar species as a basis for their domestication, mass production of larvae for repopulation experiments and for the culture of commercial‐size gar. 相似文献
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奶牛酮病发病机理研究进展 总被引：2，自引：0，他引：2
结合国内外目前研究状况较为详细的综述了奶牛酮病的病因与发病机理,并分析了奶牛酮病发生的生化机制。旨在对临床实践中很好的认识诊断和群体监控奶牛酮病提供较为系统的理论依据,保证奶牛群的高产和稳产,从而创造良好的经济效益。 相似文献
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本试验利用饲养试验方法,研究玉米-豆粕型日粮中添加植酸酶时不同磷水平和钙磷比对生长肥育猪血清指标和骨骼性能的影响。试验选用162头20kg左右的杜长大三元杂交猪进行2×3(磷水平×钙磷比)因子饲养试验,试验分2个阶段进行,前期为生长期体重在20-60kg,后期为肥育期体重为为60-100kg。结果表明:添加植酸酶日粮磷水平对血清磷含量和碱性磷酸酶的活性影响显著(P<0.05);钙磷比对血清钙和血清磷含量的影响显著(P<0.05);添加植酸酶日粮磷水平和钙磷比对生长肥育猪骨骼性能的影响不显著(P>0.05)。在添加植酸酶条件下,降低日粮磷水平不影响猪的正常生长发育。 相似文献
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“十一五”以来,我国农垦加快体制机制改革、结构调整和经济增长方式的转变的步伐,参与市场竞争,努力提升企业和产品竞争力,经济社会事业发展较快,对国家的贡献提升,职工收入、生活质量明显提高和改善,示范引领作用不断增强。本文针对农垦体制机制创新进展滞缓,战略定位与发展方向不明,经济增长方式转变和结构调整缺乏资本、人才、技术的支撑,没有处理好改革、发展、稳定、民生的关系,投资匮乏,发展后劲不足,人才短缺和劳动力素质低下的现状,提出在未来农垦体制机制创新中要特别关注改革方向、目标设定与评估,改革要在现行法律法规的框架内运作,改革时机的选择,处理好改革发展稳定与民生的关系,调整好内部利益分配关系,自觉融入区域经济,与地方协同发展等问题。为了促进农垦的发展,建议国家加大对农垦体制机制创新、现代农业建设、国有农场土地资源的保护、社会保障体系的完善等财政和政策的支持力度。 相似文献
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Abstract Catch composition, relative abundance and diversity of fish catches in open access and three old fisheries closures were compared and contrasted with previous ecological studies. There was less variation in catch community composition among the fishing grounds than the closures, suggesting that fishing has homogenised catch composition. The trap survey found that some parrotfish [ Leptoscarus vaigiensis (Quoy &Gaimard), Calotomus carolinus (Valenciennes) and Scarus ghobban Forsskål] were relatively more common and that some important predators of macro-invertebrates [ Balistapus undulatus (Mungo Park) and Cheilinus chlorourus (Bloch)] were less common in the fishing grounds than closures. Unexpectedly, and in contrast to visual census results, cumulative number of species in catch surveys was higher in open access than closures sites. This may result from fishers covering more area and habitat or a reduction in the catch of competitively subordinate and rare species by aggressive, early-caught fish that can dominate bait. Comparisons of ecological visual census surveys and fisheries-dependent methods indicated that small differences in catch composition can reflect larger ecological differences and that baiting methods can underestimate biodiversity. Ecological impacts of fishing and large-scale changes in marine ecosystems must be considerable given the many fisheries-dependent assessments report modest changes. 相似文献
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温度与盐度对老年低额蚤和蚤状蚤生长及生殖的影响王丹丽，李明云，杨天勇，胡章（宁波大学，３１５０１０）关键词老年低额 ，蚤状 ，温度，盐度，生长，生殖ＥＦＦＥＣＴＳＯＦＴＥＭＰＥＲＡＴＵＲＥＡＮＤＳＡＬＩＮＩＴＹＯＮＧＲＯＷＴＨＡＮＤＲＥＰＲＯＤＵＣＴ... 相似文献