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<正> 浮游生物是鱼类的直接或间接饵料。人们通常把水域中鱼类的自然再生产过程归结为大鱼吃小鱼,小鱼吃浮游动物,浮游动物吃浮游植物,也就是说鱼归根结底是来自浮游植物的。这种说法有一定道理,但又是不全面和简单化的。为了正确认识浮游生物在水域鱼产力中的意义,必须了解水中生物生产过程的特点。一、两种类型的生物生产过程水域中生物生产过程可以分为两种基本类型。在大洋和比较封闭性的湖泊中,生物生产过程通常从自养性生物利用太阳能把二氧化碳和营养盐类合成有机质而形成初级产量开始。初级产量为植食性动物所利用形成二 相似文献
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脂肪酸营养对鱼类生长、脂代谢及免疫性能影响的研究进展 总被引：1，自引：0，他引：1
脂肪酸在鱼类营养中起着重要的作用,脂肪酸作为能源物质为鱼类的生长发育等各项活动提供能量,并协助脂溶性维生素的吸收和体内运输。不同鱼类因其生活环境不同,对必需脂肪酸的需求种类也不同。由于不同脂肪水平与不同脂肪酸来源的饲料因其脂肪酸含量或脂肪酸组成不同,不同鱼类或鱼类的不同生长阶段对脂肪源的利用也不同,那么饲料的脂肪水平或脂肪酸组成不同就对鱼类的生长、脂代谢及免疫性能产生一定的影响作用。必需脂肪酸作为鱼类重要的脂肪酸营养物质同样影响鱼类的生长、脂代谢及免疫性能。本文从脂肪酸营养对鱼类生长、脂代谢及免疫性能的影响等方面进行综述,并对今后的研究重点进行了展望。’ 相似文献
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鱼类的生长和发育受体内各种激素的调节,其中生长激素对鱼类的生长起主要调控作用.同哺乳动物类似,在鱼类中,生长激素由脑垂体中的生长激素细胞分泌并通过血液运输到作用部位.现有研究发现,鱼类血液中生长激素的含量与鱼体生长速率的季节性变化有显著关系.因此,意味着如果人为增加鱼体中的生长激素含量,能够加快鱼类的生长,进而产生经济效益.生长激素在鱼体中含量很低,从脑垂体中大量获得生长激素用于渔业生产面临着生产效率低下、成本高等问题.这就限制了生长激素在生产中的大规模应用.但随着生命科学技术的发展,使得人们利用重组的鱼生长激素进行渔业生产就有了可能性.为此,本文就鱼类生长激素研究进展及其对鱼类生长发育影响的研究进行简要综述. 相似文献
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正饲料是鱼类正常生活和生长的物质基础,饲料所占成本占养殖生产总成本的50%~70%,降低饲料方面的成本可以在很大程度上提高养殖生产经济效益。同时,饲料在很大程度上影响着鱼类的生长状况、健康状况和鱼品的质量,所以,在养殖生产过程中使用价廉物美的饲料对于鱼类养殖生产至关重要。一、植物性鲜活饲料植物性鲜活饲料又称青饲料。草食性鱼类在野生环境中就是以青饲料为主食,所以在传统的养殖方式中,养殖草食性鱼类就是利用青饲料。青饲料,草食性鱼类喜食,生长快,疾病少,这是自然界的生物在 相似文献
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鱼类免疫学究研近十年来在国际上愈来引起科研人员的兴趣和重视。许多科研人员相继开展对鱼类免疫学的研究。最近在美国新泽西州召开的一次有关鱼类免疫学国际会议,来自18个国家隶属于政府、科学系统或者私 相似文献
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鱼类耳石研究和应用进展 总被引：6，自引：0，他引：6
鱼类耳石研究是鱼类生长和早期生活史研究的基础。文章阐述了鱼类耳石形态的研究方法及其在鱼类种类识别中的应用、耳石微结构在鱼类年龄鉴定、早期生长研究、产卵期、孵化期和产卵场的推算以及早期生活史中特殊事件的研究等方面的进展,探讨了耳石研究的存在问题并提出了进一步研究的建议。 相似文献
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溶解氧是鱼类养殖生产的重要水质指标之一,对鱼类生长、水质条件稳定、疾病防治等方面都具有重大影响。长期以来养殖生产者更多的关注缺氧死鱼对养殖生产的影响,对溶解氧不足所造成的潜在危害认识不够,在鱼类出现疾病、生长慢、产量低和养殖成本高时,找不到真正的原因,导致养殖效益受到严重影响。 相似文献
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鲤科(或包括鲤亚目、泥鳅等)鱼类的染色体试验的比较早,已能制成各式各样的倍数体和雌性发生二倍体等。一般地说,鲤科、鱼类等,不象鲑科鱼类随着成熟期出现的弊病(生长、成活率、商品价值低等)显著,致使养殖界对生产三倍体不育鱼的兴趣不大。反而积极发展雌核生殖的全雌(种苗)生产和确立早期纯系的研究。这里,概要介绍东京水产大学水产养殖学教研组和水产厅养殖研究所育种研究室共同进行的“关于通过染色体操作的鲤科鱼类全雌性生产的研究的技术。 相似文献
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Yukari Asano Ken-ichi Hayashizaki Hiroki Eda Thongkhoune Khonglaliang Hisashi Kurokura 《Fisheries Science》2010,76(5):811-817
Nile tilapia, Oreochromis niloticus, is one of the most popular freshwater aquaculture species in developing countries. Although formulated feed provides higher
fish yield, it is expensive. Therefore, fertilizer-based fish culture using natural food sources is generally implemented
in developing countries. The aim of this study was to identify the major natural foods contributing to tilapia growth in fertilizer-based
fish ponds. The stomach contents of tilapia in a fertilizer-based fish pond in Lao PDR were analyzed to estimate their feeding
behaviors; stable isotope ratios of carbon and nitrogen in the potential food organisms and suspended solids were measured
and compared with the ratios in the fish muscle tissues. Further, the feed efficiency of chironomid larvae was compared with
that of chlorella and formulated feed in a laboratory feeding experiment. Consequently, chironomid larvae were identified
as the main contributors to tilapia growth in the fertilizer-based fish pond. In conclusion, benthic larvae of insects belonging
to the family Chironomidae are confirmed to be a natural food source for tilapia in the fertilizer-based fish pond. 相似文献
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In carnivorous fish species, zooplankton is one of the main food items in the early life stages and some fish species continue feeding on such food items further along the life stages even in the farming environment. In this study, the intake of natural food items was assessed in juvenile pirarucu Arapaima gigas reared in earthen ponds. Juvenile pirarucu (12.2 ± 4.32 g and 12.1 ± 1.13 cm) were stocked in fertilized earthen ponds (240 m²). For the analysis of the fish stomach content and plankton in the pond water, the fish and pond water were sampled weekly for 75 days and biweekly until the fish reached a mean weight of 750 g. Although artificial feed was used, pirarucu also ingested the natural food available in the pond water. Among the zooplankton, pirarucu demonstrated feeding preference for cladocerans despite the abundance of rotifers and copepods. Cladocerans were present in more than 80% of the stomach contents of fish up to 300 g and in 65%, 45% and 17% of fish of 301–500 g, 501–700 g and 701–900 g respectively. Copepods were present only in fish up to 500 g at low abundance. High ingestion of insects and plant material was observed in the stomach content of fish of all size classes. The results demonstrate that juvenile pirarucu ingest natural food available in the farming pond and suggests that the adoption of pond fertilization practices may have positive effects on fish growth performance. 相似文献
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Effects of modified pond management on limnological parameters in small‐scale aquaculture ponds in mountainous Northern Vietnam 
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下载免费PDF全文 Johannes Pucher Richard Mayrhofer Mansour El‐Matbouli Ulfert Focken 《Aquaculture Research》2016,47(1):56-70
In mountainous Northern Vietnam, traditional pond aquaculture is part of the integrated farming activity contributing to food safety and to income generation for small‐scale farmers of ethnic minorities. Traditional pond management consists of a polyculture of macro‐herbivorous grass carp with 3–5 other fish species that are cultured in small ponds with constant water flow through. The main limitations to production are species‐specific mass mortalities of grass carp, a poor feed base especially for all species but grass carp, and poor water quality. In this study, we compared the traditional pond management to a semi‐intensive pond management that was based on the traditional management system but included changes designed by researchers to increase fish production. The modifications consisted of water inflow control, supplemental fertilization and feeding, and a polyculture dominated by common carp. The changes in management significantly reduced the turbidity and increased oxygen supply, as well as the natural food base within the pond. These changes in pond management provide farmers with the possibility to improve their pond aquaculture scheme and overcome previous limitations. 相似文献
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L. W. C. Lai K. K. H. Lam 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):254-266
Abstract This paper provides a case study of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong as a highly urbanized and polluted metropolis. This study lends support to the thesis that marine fish culture is generally more sustainable than pond fish culture, owing to the fact that oceanic resources are relatively less scarce than land resources ‐ even though the transaction costs of delineating and enforcing private property in the former are much higher. The case study gives a brief historical account of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong, identifies the technical inputs constraining the survival and prospects of these industries, and evaluates the relevance of the private property rights approach to their sustainability. Examination of the culture industries reveals the differences in property right characteristics of both industries. In addition to the differentiation in the degree of privatization between freshwater food fish and marine food fish culture, the major characteristics and inputs for culture practices in both industries are also examined. A qualitative evaluation of the relative significance of these inputs to the sustainability of the culture industries is provided. It is argued that the escalation in the factor price of land will destroy the local pond fish culture industry even though it is more ‘private’ than marine fish culture, notwithstanding the fact that substantial areas of intertidal ponds are owned by government and that in‐filling of fishponds have been subject to stringent planning control. The policy implications of the case study are spelled out. 相似文献
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Jeffery s. Terhune Joseph R. Tomasso Thomas E. Schwedler John A. Collier 《Journal of the World Aquaculture Society》1992,23(1):77-82
Channel catfish (lctalurus punctatus) fingerlings stocked at a rate of 450 fish/0.04 ha pond were simultaneously cultured with fingerlings stocked in 1.25 m3 cages (0, 250, 350, or 450 fishlcage; one cage/pond). The fish in the cages were cultured and harvested for a 90–330 g (whole fish) market. The fish in the open ponds were cultured and harvested for a 490–1,140 g market. Harvest weights of open pond fish in all treatments were similar indicating that the presence of the caged fish and the associated higher daily pond feeding rates did not affect open pond production. Ninety-five to 99% of the caged fish and 96 to 98% of the open pond fish were of marketable size at harvest. Survival and food conversion ratios were similar among treatments. Results of this study indicate that total pond production can be increased (in this case up to 19%) by using a combination of open pond and cage techniques and by simultaneously producing fish for two markets. 相似文献
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在3口面积各为0.3 hm^2、深度2.0 m的长方形池塘(1#、2#、3#)中放入体长0.7～0.8 cm的罗氏沼虾"南太湖2号"无特定病原种虾,密度为3.0×10~5尾/hm^2;养殖30 d时,2#、3#池塘分别混养质量3～4 g/尾的鲫鱼450、900尾,1#池塘不混养作对照组。经过近110 d的培育,1#、2#、3#池塘"南太湖2号"种虾的平均体质量分别达18.36、18.95、22.6 g,收获量分别达931.5、898.4、842.95 kg,饵料系数分别为1.36、1.53和1.71。试验结果表明,罗氏沼虾"南太湖2号"种虾培育池塘混养合理密度的鲫鱼,虽然影响种虾养殖产量,饲料系数增大,但培育出的种虾个体较大,饱满度较高,作为亲本可以为后期育苗工作的顺利开展打下良好基础。 相似文献
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《Journal Of Applied Aquaculture》2013,25(3-4):17-44
Abstract One of the most important issues concerning fish-pond fertilization is the determination of the optimal amount of fertilizer to be applied to the pond system. Another important concern is the suitability of fish species for polyculture in order to optimize production. The dynamics of nutrients, phytoplankton, and fish is a complex subject and practitioners are often compelled to formulate solutions without detailed scientific and practical consideration. The primary objective of pond fertilization is to maintain an optimal nutrient concentration for sustained biological production. Current fertilization practices in the Asia-Pacific region include: a fixed rate of fertilization and fertilization based on water color. Individual pond ecology determines how fertilization affects pond productivity, not the pond's physical location in relation to international borders. There is no universal recipe of “maximal” fertilization rates due to pond-specific variability. There is also no clear guide in the literature with regard to many aspects of fish-food; the type of organisms consumed, mechanisms of food consumption, and the digestibility and nutritive value of plankton. The usual practice is to divide fish according to their foraging in natural habitats; feeding on phytoplankton, zooplankton, zoo benthos, or detritus. The distinction between different feeding habits is not always absolute as many species of fish may change food preference depending on the abundance of different food items. This paper reviews the nutrient (nitrogen, N and phosphorus, P) management in regard to pond fertilization; use of organic and inorganic fertilizer and the impacts on fish production; use of organic fertilizer from different organisms (pig, cow and buffalo) and their interactions with primary production and water quality; optimum N:P concentration in pond water; and individual pond factors and their influence on fish production. A significant interaction was evident with time between water quality variables such as pH and alkalinity, and other factors, including manure type and fish species composition. This was reflected in the difference between pig and cow manure treatments. A significant interaction between species composition and fish production has been demonstrated. Fish survival and biomass production was influenced by the stocking ratio of the: rohu, Labeo rohita; mrigal, Cirrhinus mrigala; and Nile tilapia, Oreochromis niloticus. The recommended nutrient level for pond fertilization based on the South Australian Research and Development Institute (SARDI) and Research Institute for Aquaculture No. 1 (RIA#1) study is 1 ppm N:0.5 ppm P. The required quantity of fertilizer varies significantly with time. However, regional research is highly recommended to optimize fish production focusing on significant climate variability, which affects both primary and secondary production. 相似文献
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A study was conducted to 1) evaluate the compatibility of prawns (Macrobrachiurn rosenbergii) with carps, especially the effect of the common carp (Cyprinus carpio); and 2) measure the ability of prawns to utilize the foods available in manured systems. Carps used were the silver (Hypophthalmichthys molitrix), bighead (Aristichthys nobilis), grass (Ctenopharyngodon idella) and common carp (Cyprinus carpio). Four ponds (0.09 to 0.17 ha) were stocked with silver, bighead and grass carps while common carp were stocked in only two ponds. Total fish densities were 8,600/ha where four carps were stocked, but only 6,200/ha when common carp were omitted. Post-larval prawns (wt 0.116 g) were stocked at densities of 17/m2. Swine (approximately 60/ha of pond surface area) were housed on pond dikes so that fresh manure continuously entered each pond. Two lots of swine were fattened during the experimental period and loadings of swine manure were calculated based on hog size and feed consumption. Growth periods were 163 days for fish and 107 and 121 days for separate stockings of prawns. Gains in biomass by prawns averaged 714 kg/ha in ponds without common carp and 364 kg/ha in ponds containing common carp. Gains in biomass for both fish and prawns were 3,619 kg/ha (19.8 kg/ha/day) in ponds with common carp and 2,924 kg/ha (18.0 kg/ha/day) in those without common carp. Prawn survival was higher (X = 84.5% vs X = 72.5%), but final average weight of prawns was lower (2.64 vs 5.86 g) in the presence of common carp due to competition for food between common carp and prawns. Competition from carp is believed to have exerted less influence on prawn survival than predation on small prawns by larger, faster-growing prawns. 相似文献
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Ecological footprint for assessment of resource use and development limitations in shrimp and tilapia aquaculture 总被引：3，自引：0，他引：3
We review estimates of the spatial ecosystem support required to run a typical semi-intensive shrimp farm in a coastal mangrove area in Carribean Colombia, and to produce food inputs and process wastes for large-scale industrially managed tilapia cage culture and small-scale, semi-intensive tilapia pond farming in Lake Kariba, Zimbabwe. The tilapia farming is discussed in relation to the pelagic kapenta, Limnothrissa miodon (Boulenger), fishery and to inshore fisheries in the Lake. The results show that a semi-intensive shrimp farm needs a spatial ecosystem support—the ecological footprint—35 to 190 times the surface area of the pond, mainly mangrove area. Based on the analysis, we conclude that shrimp farming in Colombia is already utilizing close to the full support capacity of its coastal environment. In intensive tilapia cage farming, the ecological footprint for feed production is 10 000 times larger than the area of the cages. In contrast, a tilapia pond farm maintained on offals from fisheries, agriculture and households depends very little on external ecosystem areas. As long as there is a direct market for human consumption of all kapenta caught in the Lake, fish cage farming based on fish meal from kapenta would be doubtful from ethical, ecological as well as resource management points of view, even if it was economically feasible. 相似文献
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不同养殖结构鱼塘能量生态学研究 总被引：9，自引：0，他引：9
本文从养针池生态系统利用能量利用各环节,分析了两种不同养殖结构鱼生态学能量利用效率。主养草食性鱼类,其输入的总补助能,光合能、生物能的转换效率分别为９．８６％、６．９２％、１０．１０％;其生产吨鱼总补且能、光合能、生物能分别为４６．６４ＧＪ、６６．４６ＧＪ、４５．５４ＧＪ。而对于主养滤食性鲢、鳙的池塘,其对应的指标 ８．３．％、３．７５％、８．６６％、４６．９９ＧＪ、１０５．５２ＧＪ、４５．７３Ｇ 相似文献