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近年来,随着人民生活水平的不断提高,人们对水产品的要求也越来越高,以草、鲢、鳙、鲤鱼等为主的常规水产品种已满足不了人们的需要,加上一些传统的养殖方式不合理,养殖水域污染,药物以及添加剂的滥用,造成产品质量下降,致使市场疲软,养殖效益低。2003年,利津县采用养殖环境水质调控技术、 相似文献
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探讨不同养殖模式下金背鲤 (Cyprinus carpio var. Jinbei) 肠道菌群和鱼肉风味品质差异,对金背鲤的繁殖优化具有重要意义。采用高通量测序技术对稻田放养和池塘养殖模式下金背鲤的肠道微生物进行测序,利用液相色谱和顶空固相微萃取-气相色谱-离子迁移谱联用 (HS-SPME-GC-IMS) 技术测定其滋味物质、挥发性风味化合物,结合感觉阈值计算滋味活性值和相对气味活度值。结果显示:两种养殖模式的金背鲤肠道细菌群落结构差异显著,稻田放养 (FGF) 组以弧菌 (Vibrio)、拟杆菌 (Bacteroides)、交替单胞菌 (Alteromonadales)、希瓦氏菌 (Shewanella)、嗜冷假单胞菌 (Pseudomonas psychrophile) 和Brevinema属为主,池塘养殖 (FGP) 组以莫拉克斯氏菌 (Moraxella) 和克雷伯菌属 (Klebsiella) 为主;FGF组中鲜味肌苷酸含量及其滋味活性值 (1.676 g·kg−1, 6.705) 远高于FGP组 (0.246 g·kg−1, 0.985),FGF组鲜味氨基酸和甜味氨基酸含量 (0.143和2.052 g·kg−1) 高于FGP组 (0.109和2.001 g·kg−1),而其苦味氨基酸 (3.193 g·kg−1) 却低于FGP组 (3.836 g·kg−1);金背鲤的挥发性化合物组分复杂,其关键气味化合物 (ROAV≥1) 和对整体风味有修饰作用的化合物 (0.1≤ROAV<1) 的种类存在差异。菌属与风味物质的相关性分析显示弧菌属、拟杆菌属、克雷伯菌属和摩根菌属 (Morganella) 与风味物质呈显著相关 (0.01≤P<0.05 & 0.001≤P<0.01 & P<0.001)。研究表明,养殖模式影响了金背鲤的肠道微生物,并间接影响了其风味品质。 相似文献
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The Brazilian freshwater fish diversity is the richest in the world. Only 0.7% of all Brazilian species have had any aspect
of their sperm biology addressed up to this date. The majority of the fish species described in this review migrate during
the spawning season (a phenomenon known as piracema). Urbanization, pollution, hydroelectric dams and deforestation are some of the causes of stock depletion or even local extinction
of some of these species. The knowledge concerning sperm quality and minimum sperm:egg ratio is important to maximize the
use of males without reducing hatching rates. Furthermore, sperm cryopreservation and gene banking can guarantee the conservation
of genetic diversity and development of adequate breeding programs of native fish species. In this review, we present and
evaluate the existing information on Brazilian fish species that have been subject to sperm quality and cryopreservation studies.
The following parameters were evaluated: volume of extractable sperm, sperm motility, sperm concentration, freezing media,
freezing methods, and post-thaw sperm quality. Although the existing protocols yield relatively high post-thaw motility and
fertilization rates, the use of cryopreserved sperm in routine hatchery production is still limited in Brazil. 相似文献
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不同施肥方法对鱼蚌综合养殖水体水化学的影响 总被引:3,自引:3,他引:3
通过155 d的围隔实验检验了不同施肥方法对鱼蚌综合养殖水体水化学的影响.鱼蚌放养种类为三角帆蚌、草鱼、鲫、鲢和鳙,鱼蚌比例为1.5∶1.施肥处理为施鸭粪(DM)、施化肥(CF)及结合施鸭粪和化肥(DC).实验期间定期采样分析水化学指标.各施肥处理间透明度(SD)、溶氧(DO)、硫酸根离子、氯离子、碳酸根离子、重碳酸根离子、钙离子(Ca2+)、镁离子(Mg2+)、总碱度、总硬度、氨态氮(TAN)、硝酸态氮(NO3-N)、亚硝酸态氮(NO2-N)、活性磷(PO4-p)、总氮(TN)、总磷(TP)和高锰酸钾指数(CODMn)均无显著差异,但围隔CF内PO4-P/TP显著高于围隔DM,5月20日-7月18日围隔CF内pH显著低于围隔DM.随养殖时间延长,各处理围隔内SD、DO、Ca2+和Ca2 +/Mg2+呈下降趋势,但TAN、NO2-N、TN、TP和CODMn呈上升趋势.结果表明,在投喂配合饲料的基础上少量施鸭粪、化肥或结合施鸭粪和化肥不会导致鱼蚌综合养殖水体主要离子、总碱度、总硬度、TAN、NO3-N、NO2-N、PO4-P、TN、TP和CODMn含量产生显著差异.相比之下,施化肥的水体CODMn较低,PO4-P/TP较高;施鸭粪的水体CODMn较高,PO4-P/TP较低;结合施鸭粪和化肥的水体CODMn和PO4-P/TP介于施化肥和施鸭粪的水体之间.鉴于结合施鸭粪和化肥的水体珍珠产量高于单独施鸭粪或施化肥的水体,可认为该施肥措施有利于三角帆蚌生长及其珍珠囊内的珍珠质分泌. 相似文献
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本文分析比较了4种淡水网箱养鱼方式的能量效益。网箱养非鲫的能量转化效率极显著地(P<0.01)大于网箱养鲤成鱼、鲤鱼种,后两者又极显著地(P<0.01)大于网箱培育鲢、鳙鱼种。网箱养非鲫的能量生产力最高,达2.50兆焦/米~2·天,养鲤成鱼、鲤鱼种、鲢鳙鱼种的次之,分别为1.20、0.99及0.31兆焦/米~2·天,为池塘养鱼能量生产力的16~130倍。 相似文献
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Water quality fluctuations under floating net cages for fish culture in Lake Cirata and its impact on fish survival 总被引:1,自引:0,他引:1
ABSTRACT: Vertical profiles of water quality were surveyed before and after mass mortality of fish cultured in cages in Lake Cirata, a man made lake in Indonesia. The first survey was performed 4 months before the mass mortality and the second survey was carried out 4 days after the mass mortality. In the first survey, the conditions below 8 m depth were reductive and anoxic, although at 8 and 10 m depth, the water became oxidative in spite of low oxygen concentration in the second survey. These changes were probably caused by strong mixing of surface water with deeper water. Eight months after the mass mortality, when the redox potential at 8 m became reductive again, exposure tests of fish were performed in different layers in the water column around the cage. During the exposure tests the redox potential of the water was less than −100 mV and 93% of carp died within 6 h of exposure at 8 m depth. These results indicated that the mass mortality was caused by the strong mixing of surface water with reductive water in deeper layers. 相似文献
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1997年来 ,我们陆续在四川、重庆、江苏、江南、山东、北京、天津等地发现许多淡水养殖商品鱼在运输的过程中不同程度的出现死亡的情况 ,而且近年来有越来越严重的趋势 ,鱼的品种也呈现多样化 ,包括 :鲤鱼、草鱼、团头鲂、鲫鱼、斑点叉尾鱼回、长吻鱼危等。尤其在起捕热水鱼时情况更为突出 ,给许多养殖户带来了巨大的经济损失 ,面对这种情况许多人认为是由于配合饲料的原因引起的 ,对此我们在全国大范围的地区进行了广泛的调查和分析。发现造成鱼不耐运输的因素是多方面的 ,而单纯认定属饲料问题是不科学的 ,也是不客观的。主要症状 :1、运… 相似文献
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Reduction of a native fish fauna by alien species: an example from Brazilian freshwater tropical lakes 总被引:1,自引:0,他引:1
The consequences of introducing Cichla cf. monoculus Spix & Agassiz, Astronotus ocellatus (Agassiz) and Pygocentrus nattereri Kner into lakes in the River Doce basin, Brazil, on richness, diversity and efficiency of aquatic macrophytes as natural refugia to native fishes was investigated. Samples were taken from lakes with and without alien fishes in areas with and without aquatic macrophytes. The presence of alien fishes reduced richness and diversity of the native fish community. The refugia function, which could be attributed to the clustering of aquatic macrophytes, does not exist in these lakes probably because the alien fishes exploit such habitats for reproduction. Since introductions threaten the native fish diversity of the region, studies on regional dispersion and factors that minimise the spread of alien fishes are needed. 相似文献
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目前黄鳝养殖在我国的河南信阳、湖南、湖北、江西、安徽、四川等地已逐步发展并形成一定的规模.尤其是河南信阳以及湖南、湖北更是发展非常迅速。现已形成许多的专业养殖乡镇。 相似文献
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对虾养殖过程中的水质控制 总被引:5,自引:0,他引:5
一、水质因子对养虾的影响及对虾养殖对水质的要求在水产养殖的过程中,通常用溶解氧、pH值、氨氮、硫化氢、盐度、水色、水的味道和透明度来表示水质化学指标和物理性状。溶解氧不仅是保证对虾正常生理功能和健康生长的必需物质,又是改良水质和底质的必需物质,在对虾养殖的全过程中均应保证有充足的溶解氧,最好能保持在5mg/L以上。养殖南美白对虾底层水一般不应低于3.5mg/L,当溶解氧降到1mg/L时,南美白对虾便有浮头死亡的危险;养殖中国对虾底层水一般在短时间内不得低于4mg/L。池塘底质和水中浮游生物也需要消耗大量的溶… 相似文献
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Cultivation of a species or population and distribution to various regions has raised the idea of negative impacts on native species. The effect of non‐native species on native species may be caused by competition for source, predation, hybridization, and parasite/disease transport. The present study aims to evaluate the possible effects of a trout farm established on the banks of Kocaba? Stream (Çanakkale, Turkey) on feeding characteristics of some freshwater fish (Phoxinus phoxinus, Barbus oligolepis, and Squalius cii). The samples were collected monthly over a year at two stations located before and after the trout farm and at a control station on the tributary not impacted by the effects of the farm. Fish and environmental samples were gathered monthly with an electroshocker and some fishing tools between August 2015 and July 2016. The fish diet and resource incorporation into biomass were evaluated by gut content and stable isotope analyses. Changes in diet preferences when the species are exposed to source stresses and some individuals fed on farm‐based feed contaminated from the farm in Kocaba? Stream. In this study, it was observed that native fish populations in aquaculture regions were influenced by diet preferences. Designing enclosed systems limiting feed and waste transit in aquaculture establishments may be suitable for sustainability of these species. 相似文献
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H. Chaudhuri R.D. Chakrabarty P.R. Sen N.G.S. Rao S. Jena 《Aquaculture (Amsterdam, Netherlands)》1975,6(4):343-355
Composite fish culture of the Indian major carp, Catla catla, Labeo rohita and Cirrhinus mrigala together with the Chinese silver carp Hypophthalmichthys molitrix and grass carp Ctenopharyngodon idella and the Indonesian strain of common carp (Cyprinus carpio communis) was carried out in experimental ponds in 1971–1972 and 1973–1974. The management techniques adopted aimed at high yields of marketable fish (around 1 kg) in 1 year.In the first year, production varied from 3 889 to 5 600 kg/ha/year and this rose to an average of 8 200 kg/ha/year with a maximum of 9 389 kg/ha/year in the second year. The important changes made to the management schedule in 1973 were increased stocking density, greater use of feed and fertilizers, and provision of more weeds for grass carp.The experimental studies demonstrate the practicability of raising large crops of healthy marketable fish in India. 相似文献
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Dual-purpose reservoirs for field irrigation and fish culture are characterized by the simultaneous (a) increase in standing crop biomass and feeds during the fish culture period and (b) decrease of water level due to irrigation. This management practice affects stratification, which in turn affects water quality and may affect the fish stocked. To study the limnology of dual-purpose reservoirs, an extensive sampling programme including automatic continuous recording and manual water sampling in deep and shallow reservoirs was carried out. This paper describes limnological changes during the week in which a 3 month long seasonal stratification ended and fish kills occurred. Management implications of stratification are also discussed. The data presented are the first continuous records of this process in this particular type of water body. 相似文献
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Use of artificial substrates to enhance production of freshwater herbivorous fish in pond culture 总被引:1,自引:0,他引:1
P Keshavanath B Gangadhar T J Ramesh J M van Rooij M C M Beveridge D J Baird M C J Verdegem & A A van Dam 《Aquaculture Research》2001,32(3):189-197
Two trials were conducted in mud‐bottomed concrete tanks to assess the potential of using artificial substrates to enhance fish production in ponds. Three substrate types were tested: bamboo poles, PVC pipes and sugarcane bagasse bundles. In one trial, periphyton was grown on the substrates in the absence of fish. In the second trial, masheer (Tor khudree Sykes) fingerlings were stocked at three densities. Results showed a significant effect of substrate type on fish growth (P≤ 0.001) and on net fish production (P≤ 0.05), with best growth in the tanks using the bamboo substrate. In the bagasse treatment, 100% fish mortality occurred. Highest extrapolated periphyton‐based gross fish yield (i.e. without feed inputs) was 450 kg ha?1 90 d?1 with PVC and 491 kg ha?1 90 d?1 with bamboo substrate. The best periphyton growth occurred on bamboo, followed by bagasse and PVC. Without fish, mean periphyton biomass during the culture period was 0.56–1.20 mg cm?2 on bamboo [ash‐free dry matter (DM)], against 0.09–0.36 mg cm?2 on PVC and 0.20–0.59 mg cm–2 on bagasse. No clear effect of fish density or water depth on periphyton biomass could be seen. Only on bamboo, fish density seemed to have a negative effect on periphyton ash‐free dry matter and a positive effect on pigment content (chlorophyll‐a and phaeophytin). Periphyton from bamboo had a lower ash content (38–47% of DM) than from PVC (54–55% of DM) or bagasse (51–58% of DM). It is concluded that substrate type has a strong effect on periphyton productivity and composition, and on fish productivity. Good fish production was achieved without feed inputs. More research is needed to study the economic viability of periphyton‐based systems in the context of Indian aquaculture. 相似文献