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黄颡鱼人工繁殖及鱼苗培育试验 总被引：7，自引：0，他引：7
以鲜鱼虾肉、自制配合料为饵料，在室内和室外水泥池内进行黄颡鱼亲鱼培育；采用DOM、PG、LHRH－A2、HCG不同剂量组合进行人工催产；采用静水和微流水两种方法进行孵化。在孵化网箱内进行鱼苗培育。结果表明：黄颡鱼亲鱼喜食新鲜饵料，也易驯食配合饲料，室内和室外人工条件下均能获得成熟亲鱼；用DOM＋HGG＋LHRH－A2或PG＋HCG＋LHRH－A2的混合剂人工催产，微流水孵化效果较好，催产率为50％－1005，受精率为60％－90％，孵化率达70％－90％；小网箱培育鱼苗，成活率高，规格整齐。 相似文献
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以人工养殖的巴丁鱼(Pangasianodon hypophthalmus)亲本为试验对象,开展了注射不同外源激素诱导巴丁鱼排卵和人工催产试验。结果表明,采用注射促黄体素释放激素类似物LHRH-A和地欧酮DOM药物组合的林彼方法,注射剂量为(10μg LHRH-A+5 mg DOM)/kg鱼体质量,可促进巴丁鱼血清促性腺激素Gt H水平在短期内迅速升高,并成功诱导巴丁鱼排卵,催产率100%,排卵率100%,高于其它试验组。当水温在26~33℃时,采用林彼方法进行了7批次催产工作,注射剂量为(6~7μg LHRH-A+5 mg DOM)/kg鱼体质量,效应时间9.0~13.5 h,平均催产率80.6%,排卵率100%,生产性试验共获得巴丁鱼卵黄苗2430万尾。 相似文献
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从试验研究和生产实践中总结出细鳞鲴规模化人工繁育技术,对具体技术进行了描述、量化说明和讨论。细鳞鲴规模化人工繁育是项综合技术,其关键技术是催产药物配伍及其用量、自然产卵受精脱粘材料的选用和鱼苗至夏花阶段的培育。最佳的催产药物是促黄体素释放激素LHRH—A2＋地欧酮（DOM）＋绒促性素（HCG）,雌鱼剂量（LHRH—A210μg＋DOM5mg＋HCG300 IU）／kg,雄鱼减半。自然产卵受精脱粘材料宜选用滑石粉、食盐液（滑石粉200g、食盐25g加水5kg搅匀）。鱼苗至夏花阶段的关键是要培育适口的天然饵料和掌握鱼苗下塘时机。 相似文献
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欧洲丁鱥人工繁殖的亲鱼以3～4龄较好，个体要求雌鱼到达400g，雄鱼到达250g以上；催产时间（鹰潭地区）为4月下旬-5月中上旬为好；适宜水温为18～30℃，最适水温为25～28℃，32℃以上时产卵率、受精率和孵化率都较低；催产激素可选择混合激素，剂量为50μg/kg LHRH—A2和5mg／kg DOM合剂；催产方法以两针注射法为好，针距为8～10h；效应时间（水温25℃时）为11—16h；产卵既可自然产卵也可人工授精，孵化一般在网箱中充氧孵化即可，有条件的地方可以实行脱粘后在环道或孵化漕中进行孵化。三年的最高产卵率87％、受精率91％、孵化率93％。 相似文献
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尖头金线鲃人工繁殖初步研究 总被引：3，自引：0，他引：3
用人绒毛膜促性腺激素（HCG）、促黄体素释放激素类似物（LRH—A2）、马来酸地欧酮（DOM）组合对尖头金线鲃（Sinocyclocheilus oxycephalus）催产获得成功,用鲤脑垂体5mg／kg和人绒毛膜促性腺激素1000IU／kg组合催产失败。采取2次注射（第1次注射LRH—A2 2μg／kg,第2次注射LRH—A2 8μg/kg＋DOM3mg／kg＋HCG 1000IU／kg）催产效果明显;采取遮光孵化,孵化率明显提高。 相似文献
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通过对鸭绿沙塘鳢(odontobuds yaluensis)亲鱼培育、人工催产和孵化技术的初步研究,旨在完善其规模化人工繁殖及育苗技术,为大规模人工繁殖和养殖奠定基础。结果表明,人工催产显著提高了鸭绿江沙塘鳢的产卵率,即采用两次肌肉注射,催产剂为促黄体素释放激素A2(LHRH一A2),地欧酮(DOM)及绒毛膜促性腺激素(HCG);最佳剂量第一次注射:LHRH-A24.0μg/kg、DOM 2.0mg/kg、HCG 300IU/kg;第二次注射:LHRH-A28.0μg/kg、DOM 5.0mg/kg、HCG 1 500IU/kg,产卵率20%,产出卵受精率达61%。采用不间断充气和定期换水孵化,孵化率和仔鱼成活率分别为40%和53%。 相似文献
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用DOM3－5mg＋LRH－A50－100μg/kg人工催产细鳞斜颌鲴2批，共134尾，其中雌（♀）90尾、雄（♂）44尾。催产率100％，受精率70％以上，出苗率40％－80％。获卵916万粒，鱼苗409万尾。 相似文献
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对人工驯化的黑尾近红鲐进行人工药物催情、产卵和孵化。结果表明：用激素PG＋HCG＋LRH—A2、HCG＋LRH—A24-DOM、PG4-LRH—A2＋DOM、HCG＋LRH—A：组合催情,催产率100％,受精率72．4％～97．9％,孵化率63．80％～80．4％。 相似文献
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丁鱥(TincatincaL.)引种驯养和人工繁育的初步研究 总被引：15，自引：0，他引：15
从新疆引入丁Gui（Tinca tincaL.）鱼种进行驯养，并于次年春季选成熟亲鱼作人工繁殖和苗种培育试验。结果表明：丁Gu移养在浙江地区，能较好地生存，生长速度较快；配制的人工饲料能满足其生长需要；丁Gu在平均体重达200－250g时性成熟，催化产激素的LHRH－A2及HCG与DOM的混合制剂，在水温19－23℃下，效应时间为16－19h，催产率分别为100％和76％，两次人工催产均获成功，共产卵20万粒和45万粒，受精率分别为86％和665，胚胎发育时间在水温19．8－22．5℃下约47h左右，孵化率分别为53％和42％；采用江浙的“豆浆法”培育丁Gu鱼苗，经25d左右的饲喂，平均规格达3－4cm，平均成活率为38％和35％。 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