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暗纹东方鲀(Fugu obscurcs)俗称河豚,为江海洄游性鱼类,历誉"鱼中之王",驰名中外,具有极高的经济价值和药用价值.随着暗纹东方鲀在国内养殖的迅猛发展,苗种的运输已成为首要制约其养殖的重要环节.笔者在进行暗纹东方鲀的研究和开发期间,分别在冬季(1月)和夏季(5月~8月)从江苏与上海11次运输暗纹东方鲀苗种90310尾到江西省九江市,历经10小时~17小时,成活率57.82%~100%.现将运输结果报告如下,以进一步提高苗种运输成活率及为成鱼的运输提供参考. 相似文献
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池养无毒暗纹东方鲀的人工繁殖 总被引:5,自引:0,他引:5
研究了温室(18~25℃)池养暗纹东方鲀性腺发育、人工繁殖和河鲀毒素.试验结果表明池养暗纹东方鲀雄鱼成熟系数二、三月份达到最大值分别为0.1480±0.0100和0.1317±0.0l40;三、四月份雌鱼成熟系数达到最大值分别为0.2440±0.0400和0.3058±0.0460.与野生的暗纹东方鲀相比较,经统计检验,P>0.05,成熟系数无显著性差异.池养暗纹东方鲀不经降海洄游,性腺完全能发育成熟,能进行人工催产并孵化得苗,并且证明活体各部分均无毒或弱毒,这对于大规模开展暗纹东方鲀的人工养殖具有重要意义. 相似文献
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利用褶皱臂尾轮虫和暗纹东方鲀鱼苗在5‰的咸淡水中都能够存活的特点,用面包酵母培育褶皱臂尾轮虫经海水小球藻强化培育后在5‰的盐度条件下投喂暗纹东方鲀鱼苗,结果表明,褶皱臂尾轮虫较之淡水轮虫可使暗纹东方鲀鱼成活率显著提高。 相似文献
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暗纹东方鲀养殖关键技术浅析 总被引:1,自引:0,他引:1
<正>暗纹东方鲀俗称"河豚",其肉质鲜美,但含剧烈神经性麻痹毒素。暗纹东方鲀属海江生殖洄游鱼类,是我国长江下游地区重要的渔业资源。随着环境变化以及人类活动的影响,野生的暗纹东方鲀资源日渐稀少,江苏省扬中市水产技术研究所从1995年起开展了暗纹东方鲀的人工繁殖和养殖技术研究。目前,人工养殖的暗纹东方鲀已经全面取代了野生的暗纹东方鲀成为了食用鱼源。本文所要探讨的便是人工养殖暗纹东方鲀的一些关键技术。 相似文献
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河鲀鱼泛指硬骨鱼纲、鲀形目、鲀科的各属鱼类,因体形似豚,常在河口捕获,故江浙一带俗称"河豚".河鲀鱼在世界各地分布较广,品种较多,现初步查明有43种,其中在我国就有35种,大部分是东方鲀属,分布在东海、黄海、渤海.我国是河鲀鱼生产量最多的国家,年产量约在3~4万T,占世界河鲀鱼产量的70%左右.近年来几种主要东方鲀品种的人工繁殖和苗种培育的成功,加速推进了我国河鲀人工养殖的发展,产量、外销量不断增加.目前主要养殖区域分布在辽宁、河北、山东、福建和江苏等地.主要养殖品种有红鳍东方鲀、假睛东方鲀、暗纹东方鲀等.在淡水中养殖的河鲀鱼主要为暗纹东方鲀,近年来养殖规模逐年扩大,已成为一个新的较有发展前途的淡水名特优养殖品种.随着人们对河鲀鱼认识的逐步深入,其身价与日剧增,市场需求不断扩大. 相似文献
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关键种对生态系统结构和功能发挥了重要作用,其变化可以引起群落结构振荡和演替,导致生态系统功能紊乱乃至崩溃,因此,了解生态关键种的长期变化有助于解析整个生态系统演替过程。本研究基于莱州湾1959年、1982年、1993年、2003年和2015年春季(5月)底拖网渔业资源调查数据,构建了莱州湾春季鱼类群落食物网拓扑结构,分析了其关键种的长期变化。1959~2015年莱州湾鱼类食物网包含物种21~46个,摄食关系范围70~296个,食物网拓扑结构密度范围为0.155~0.300,种间关联度0.140~0.182,符合自然条件下群落种间摄食关系。1959~2015年莱州湾鱼类群落关键种如下:1959年为六丝矛尾虾虎鱼(Amblychaeturichthys hexanema)、花鲈(Lateolabrax japonicus)、蓝点马鲛(Scomberomorus niphonius)和黄(Lophius litulon),1982年为鳀(Engraulis japonicus)、黄和小黄鱼(Larimichthys polyactis),1993年为带鱼(Trichiurus lepturus)、鳀和蓝点马鲛,2003年为细纹狮子鱼(Liparis tanakae)、鳀和黄,2015年为细纹狮子鱼、大泷六线鱼(Hexagrammos otakii)和六丝矛尾虾虎鱼;关键种由经济价值较高的花鲈、小黄鱼和蓝点马鲛等演变为细纹狮子鱼、鳀和六丝矛尾虾虎鱼等经济价值较低的种类;同时,关键种的栖息环境也由中上层与底层生境(蓝点马鲛、花鲈、鳀等)演变为底层单一生境(细纹狮子鱼、大泷六线鱼和六丝矛尾虾虎鱼);关键种的这种更替导致食物网拓扑结构向简单化发展,在某种程度上也增加了鱼类群落结构脆弱性。 相似文献
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20 0 1年我们与河北水利厅合作 ,特聘请上海水产大学的专家对我们这里的三座水库进行资源调查 ,专家们认为小海子水库是天然的养蟹基地。这是一个浅碟型平原型水库 ,库底平坦 ,水草丰茂 ,枯水季节生长的水草可达水面 70 %左右 ,底部腐植淤泥层厚 15cm左右 ,水色呈绿褐色 ,透明度在5 0~ 80cm ,日照时间长 ,日照数波动在 12 2 7~2 74 8h ,年平均气温为 13 5℃ ,日平均气温变动在 - 4 7~ 2 8 2℃之间 ,库区最高气温 39 8℃ ,最低 - 13 8℃ ,月平均水温变化为 2 4~ 2 2 9℃之间 ,月平均最高水温在 7月和 8月 ,最低在 12月和 1月。由于水… 相似文献
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C.D. de Silva 《Aquaculture International》1997,5(4):339-349
An electrophoretic analysis of six populations of Oreochromis mossambicus (Peters) and four populations of O. niloticus (L.) from several rivers and a fish hatchery in Sri Lanka was conducted to determine the degree of mixing within and between stocks. Genetic characterization of the O. mossambicus stocks showed that some degree of mixing with O. niloticus occurred in all but two of the populations examined, while in the case of the O. niloticus, all the populations had some degree of mixing of O. mossambicus alleles. Genetic identity calculated using Nei's coefficient gave values ranging from 0.9484 to 0.9895 for O. niloticus populations and 1.0 to 0.9940 for O. mossambicus populations, while interspecies comparisons ranged from 0.7531 to 0.9002. The implications of these results for fisheries management and aquaculture are discussed. 相似文献
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M. W. APRAHAMIAN P. HICKLEY B. A. SHIELDS G. W. MAWLE 《Fisheries Management and Ecology》2010,17(2):93-105
Abstract Inland fisheries in England and Wales have high economic and social values. Managing participation to maximise fishery performance is key to maintaining this status. The capital value of fishing rights for migratory salmonid fisheries is €165 million. Coarse fisheries contribute €1030 million to the economy. The central tenet to increasing participation in recreational salmonid fisheries is that an increase in stock size will result in more anglers accessing the fishery. This was examined for salmon on the rivers Usk and Lune where exploitation restrictions increased the number of salmon available to anglers. On the River Lune, the number of salmon available post‐intervention increased by 66%. There was no significant increase in catch while the number of anglers decreased by 16.3%. On the River Usk, the closure of the net fishery potentially resulted in an additional ~1200 salmon being available. Following closure, there was no significant change in rod catch or in the number of anglers. Increased participation is dependent less upon stock manipulation for coarse fisheries and more upon facilitating the activity. In recent years, urban fishery development programmes have provided improved access to local fishing opportunity. Also, new anglers have been targeted through campaigns such as Get Hooked on Fishing and the Scout Angler Badge. 相似文献
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César Salazar Marcela Jaime Yanina Figueroa Rodrigo Fuentes 《Aquaculture Economics & Management (Blackwell Science)》2018,22(2):151-167
In light of the current depletion of extractive marine resources and the sustainability issues that have arisen in the aquaculture industry, the small-scale aquaculture sector has emerged as a viable and sustainable alternative for generating income. To integrate the small-scale aquaculture sector into the food value chain, understanding the decision-making process to innovate becomes essential. This paper explores the factors underlying both innovation choices and intensity among small-scale aquaculture producers by utilizing exclusive census data from the small-scale aquaculture sector in Chile. The results indicate that education, secure property rights, internet access, participation in organizations, commercialization methods, government instruments, understanding of credit, and social learning promote innovation decisions. We also find that largest producers innovate in more areas, suggesting a role of size for both technological and non-technological innovations. 相似文献
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为研究斑海豹生长规律,达到科学饲养的目的,对大连圣亚旅游控股股份有限公司豢养斑海豹进行体检,获取动物性别、年龄、体质量和体长等信息;通过SPSS 13.0软件对动物的生长曲线、体长-体质量关系和雌雄间生长差异进行分析。试验共获得30头豢养斑海豹的体检数据,雌性11头,雄性19头。统计分析发现:logistic、Gompertz和von Bertalanffy三种模型回归的斑海豹最大体长、体质量依次为167、170、171 cm和153、175、191 kg ;体质量-体长关系为(r2=0.908);研究还发现体长-年龄、体质量-体长间的相关关系模型能够较准确的反映斑海豹的生长规律,而体质量年龄模型准确度较差。控制年龄的协方差分析未发现雌雄斑海豹生长规律间的差异(体长:P >0.05;体质量:P >0.05)。 相似文献
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To validate the involvement of meiobenthos in cellulose breakdown in wetlands, meiobenthos were collected from sediments of
Lake Furen and the Biwase River in Hokkaido Prefecture, the Kako River in Hyogo Prefecture, and the Chinai River in Shiga
Prefecture. Cellulase activities of the meiobenthos were measured by cellulose zymographic analysis using sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDS-PAGE) gels containing 0.5% carboxymethyl cellulose. The results showed that most of
the Turbellaria, Nematoda, Harpacticoida, and Oligochaeta species exhibited cellulase activity. The molecular sizes of the
cellulase-active bands of the sediments in Lake Furen, the Biwase River, and the Chinai River coincided with those of meiobenthos.
The findings suggest that meiobenthos might play a major function in cellulose breakdown in these wetlands. This paper is
the first to report cellulase activity in meiobenthos and that they are possibly involved in the breakdown of cellulose in
wetlands. 相似文献