大规格黑鲷土池养殖技术

2004年我们利用越冬的黑鲷鱼种,开展了池塘养殖工作,经过近一年的养殖,取得了较好的效果,现将养殖技术介绍如下:一、试验条件与方法1.池塘条件选择连云港高公岛附近虾塘一口,面积约30亩,平均水深1.6米,底质为泥沙底质,周围海区无工业污水和生活污水流入,可直接从海区纳水。日最     

海水土池育苗适口饵料生物培育技术

海水土池育苗可以利用池塘中天然饵料生物，因其具有成本低、收益好等特点而越来越受人们的欢迎。近几年来，河蟹土池育苗已兴起热潮，海水鱼类、贝类、虾蟹的土池育苗也已开始。但由于种种原因，土池育苗生产很不稳定，甚至失败，其中原因之一是育苗培育时饵料供应不足，营养不全面或是质量不好。浮游生物是多数鱼、贝、虾、蟹幼体的开口饵料、基础饵料，或是补充饵料，在育苗工作中起着重要的作用。搞好海水土池育苗，培育适口饵料生物是育苗的关键技术之一。在此介绍一些海水土池育苗中如何培育适口饵料生物的方法。     

大棚土池河蟹育苗技术

大棚土池河蟹育苗以其投资少、易启动、风险低、效益高的优势，成为苏东沿海民间投资的重要项目之一。笔者在广泛调查研究的基础之上，结合自己的育苗操作，就大棚土池河蟹育苗技术提出改进措施，现总结如下。１　基建工艺的改进 基建工艺的科学性，是育苗稳产、高产的基础。目前，大棚土池育苗生产中在基建方面存在以下三方面的不足。１．１ 池口面积 现在多数育苗水池的单口面积在４０～５０ｍ２，有的甚至达到８０ｍ２。大水体育苗的优点在于育苗前期水质稳定，但是Ｚ４以后，大水体的缺点便暴露出来：一是水质更新困难，水体大使换水的…     

河蟹土池人工育苗试验

为了研究北方河蟹士池人工育苗技术,辽宁省盐碱地利用研究所水产研究室于1990年5月5日～6月11日在盘锦市大洼县于树农场对虾养殖场新开挖的土池中进行了河蟹人工育苗试验。试验面积450m~2,培育出大眼幼体20万只计1.25kg,折亩产1.865kg。     

青蛤土池人工育苗试验

<正> 为了获得低价的青蛤苗种进行滩涂增殖,1998年7月至1999年6月,利用新建土池进行了青蛤人工育苗试验,在0.47hm~2土池中进行了亲贝暂养,诱导产卵、受精孵化、浮游幼虫培育、稚贝附着及洗苗移养试验。越冬前获得2—8mm稚贝454万粒/0.067hm~2。越冬后稚贝成活81.4万粒/0.067km~2,实验证明,在北方地区用土地进行青蛤育苗是完全可行的。     

泥螺土池育苗技术

泥螺（Bullactaexarata）隶属于软体动物门、腹足纲、后鳃亚纲、头目、阿地螺科，是滩涂常见小型经济贝类，广泛分布于我国南北沿海潮间带滩涂。为了有效解决目前我市泥螺苗种的短缺问题，我市黄海滩涂开发集团有限公司率先对泥螺土池育苗技术进行探索，找到了一条行之有效的路子。现将泥螺土池育苗技术总结如下，供养殖者参考。一、生活习性泥螺是一种广温广盐性品种，其生存温度为－１．５～３３℃，最适温度为１０～２５℃，盐度适宜范围为８‰～２８‰，pH最适范围为７．１３～８．０１。泥螺为舔食性腹足类，摄食时翻出齿舌在滩面上舔…     

河蟹土池育苗高产试验

自上世纪70年代起，我国的河蟹人工繁殖研究先后解决了亲蟹饲养运输、交配产卵、越冬孵化、幼体培育和蟹苗暂养等一系列技术问题；90年代后期，河蟹土池育苗技术日趋成熟，给河蟹养殖业的快速发展奠定了基础。笔者总结前几年河蟹土池育苗经验的基础上，在布苗、饵料等方面进行了技术改进，2003年7口试验池塘，总面积7亩(15亩=1公顷，下同)，共育出大眼幼体226kg，平均亩产32．4kg，产值13．56万元，利润5．03万元。现将试验情况报告如下：     

大棚土池河蟹人工育苗

江苏如东沿海部分群众近几年利用大棚土池进行河蟹人工育苗。从这几年的生产实践来看，大棚土地河蟹人工育苗投资成本低，设备简单易操作，回收效益系数较高。 一、建池要求 利用蟹池平田或临近海水资源的空地开挖一些池子。池子以３０－４０米２为宜，深度一般在１．１０－１．３０米之间；池四角呈弧形（半圆角）、坡度控制在１：１．５。池口由上向下５０厘米用黑色薄膜紧贴坡钳固。池底为促底，用生灰（扬开）拌土加少量水筑平，也可铺沙５厘米左右。充气石一般每０．８－１．０米２一只，用小竹签绑好钉于池底，气石悬在离底５－８厘米…     

泥螺土池育苗技术

泥螺(Bullacta exarata)隶属于软体动物门、腹足纲、后鳃亚纲、头楯目、阿地螺科,是滩涂常见小型经济贝类,广泛分布于我国南北沿海潮间带滩涂。近年来,泥螺养殖在启东市发展迅速,规模不断扩大,产量不断增加,已逐渐形成泥螺育苗、养殖、加工一条龙的生产格局,成为启东市海水养殖的主要养殖品种之一。随着泥螺养殖规模的不断扩大,泥螺苗种的需求量也随之加大。为了有效解决目前启东市泥螺苗种的短缺问题,启东市黄海滩涂开发集团有限公司率先对泥螺土池育苗技     

大棚土池河蟹人工育苗研究

近年来,由于成蟹市场行情看好,而天然蟹苗量骤减,沿海地区河蟹育苗逐渐风行,各地兴建、改建许多育苗场。土池育苗也逐步增加,但土池育苗由于受气候影响较大,综合管理难以规范化,产量丰欠不稳,单产较低。本人就河蟹人工育苗之原理,设计用大棚土池,模拟厂房进行土...     

河蟹生态育苗过程中二次消毒与苗产量的关系

河蟹生态育苗技术经过几年的研究,已经初步成熟,有关学者对各种生态因子对蟹苗产量的影响进行了较多研究[1-3]。对于pH值的适宜范围,很多学者有针对性地作了不少研究,鱼类养殖的适宜pH一般为7~8.5,超过9以上无论是养成还是育苗,成功的机会均会大大降低[4]。房文红等只做过对虾溞状幼体与pH值的研究[5],认为饲养水的pH值增加会导致前期溞状幼体和后期幼体的存活率明显降低,但pH值对河蟹溞状幼体影响的报道甚少,本文通过探讨河蟹两次消毒和pH值及苗产量间的关系,以期为生产提供参考依据。1材料与方法1.1试验池试验池148口,每口2 hm2,但由于…     

Relationship between zooplankton abundance and the early marine life history of juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> in eastern Hokkaido,Japan

Interannual variations in abundance, timing of outmigration from rivers, growth rate and condition of juvenile chum salmon (Oncorhynchus keta) were studied in the Nemuro Strait (eastern Hokkaido, Japan) during 1999–2002 to establish a possible relationship to zooplankton abundance. The otolith microstructure of juveniles was examined each year in late June to determine their time and size at sea entry (i.e., outmigration), and to estimate the early marine growth rates. Salmon outmigration peaked in mid- or late May, which coincided, in three of the four study years, with the peak release of juveniles into rivers within the study area. Abundance, growth rate and condition of fish were higher in 2001, when—compared to other years—smaller fish experienced higher growth rates, coinciding with greater zooplankton abundance for that year. Our results suggest that high zooplankton abundance positively influenced juvenile chum salmon growth and the condition of the fish during their early marine life despite their small size at sea entry.     

博斯腾湖哲水蚤种群消失与池沼公鱼的关系

哲水蚤目(Calanoida)是水体中的浮游生物主要种类组成之一,也是各种幼鱼和食浮游生物鱼类良好的天然饵料,其种类组成及数量变动往往直接制约经济鱼类的丰度.哲水蚤摄食浮游藻类、细菌及腐屑,对藻类的生长、防治水体富营养化和水体自净起到重要作用,在生态系统物质循环和能量流动中起着至关重要的作用.采用<内陆水域渔业自然资源调查手册>有关方法,1984～2006年,以新疆博斯腾湖哲水蚤和池沼公鱼(Hypomesus olidus)为研究对象,通过对哲水蚤种类、数量和生物量的变化及对池沼公鱼生物学食性、种群数量进行长期观察,结果表明,在各种食物都比较丰盛时,公鱼摄食哲水蚤的出现率最高(41.6%),池沼公鱼种群数量的大量增加导致了哲水蚤逐渐减少乃至消失.     

微环流技术在土池鳗鱼健康养殖中的应用研究

本文着重介绍微环流技术的原理与结构,以及在试验中的应用结果,旨在探讨推广微环流养殖技术新模式的可行性和必要性。通过微环流技术在土池养鳗中应用结果表明：试验池整个系统运转正常,水质指标稳定,试验期间未发生鳗鱼疾病,且绝对增重量高于对照池1．64倍,起到增产、增效、节能及改善池塘环境等效果。该池塘养殖新模式如加以推广,对提升养殖品种的品质与经济效益,实现健康、绿色、无公害养殖,有着广阔的前景。     

The in vivo incorporation and metabolism of [1-14C] linolenate (18:3n-3) in liver, brain and eyes of juveniles of rainbow trout Oncorhynchus mykiss L and gilthead sea bream Sparus aurata L.

Accumulation of docosahexaenoic acid (DHA; 22:6n-3) in brain and eyes during development has been demonstrated in fish but it is not clear whether liver or neural tissues themselves are of greater importance in the biosynthesis of DHA from dietary 18:3n-3. In the present study, we investigated the in vivo metabolism of intraperitoneally injected [1-¹⁴C]18:3n-3 in liver, brains and eyes of young juvenile fish. Metabolism was followed over a 48h time-course in order to obtain dynamic information that could aid the elucidation of the roles of the different tissues in the biosynthesis and provision of DHA from dietary 18:3n-3. The study was performed in both a freshwater fish, rainbow trout Oncorhynchus mykiss L and a marine fish, gilthead sea bream Sparus aurata L to determine the effect that low or limiting5-desaturase activity may have in this process. As expected, the results showed that although the sea bream incorporated more 18:3n-3 into its lipids, metabolism of the incorporated fatty acid by de saturation and elongation was generally greater in the trout. In liver, the percentages of radioactivity recovered in tetraene and pentaene products were greater in trout than in sea bream although there was no difference in hexaenes. In contrast, the re covery of radioactivity in DHA was significantly greater in brain in trout compared to sea bream. In both species, the percentage of radioactivity recovered in desaturated/elongated products was much lower in liver than in brains and eyes, but that percentage increased over the 48h time-course. In trout though, the highest percentages of desaturated products in brain and eye were observed after 12 and 24h, respectively. However in sea bream the highest percentages of desaturated products in the neural tissues were observed after 24-48h. Radioactivity was recovered in 24:5n-3 and 24:6n-3, intermediates in the 4-independent ("Sprecher shunt") pathway for the synthesis of DHA, in both species, especially in the brain and eyes. Overall, although the results cannot eliminate a role for liver in the biosynthesis and provision of DHA for developing neural tissues in fish, they suggest that DHA can be synthesised in fish brain and eye in vivo.     

Relationship between metabolic rate in vitro and body mass in a marine teleost,porgy Pagrus major

The rate of oxygen consumption of minced whole body was determined volumetrically, as an indication of metabolic rate in vitro (M _{in vitro} ), at 20°C in porgy Pagrus major ranging from 0.0002 g (just after hatch) to 2.9 g (67 days old) in body mass. A triphasic relationship was found between M _{in vitro} of individual fish (l.min^–1) and wet body mass W (g). During the prolarval stage accompanied with the transitional period to the postlarval stage (0.00020–0.00023 g, 0–6 days old), the mass-specific metabolic rate in vitro (M _{in vitro} /W in l.g^–1.min^–1) increased with age (D in days) as expressed by an equation M _{in vitro} /W = 3.88 + 0.74/D. During the postlarval stage (0.00031–0.003 g, 8–22 days old), M _{in vitro} /W remained almost constant, independent of body mass following an equation M _{in vitro} /W = 5.24 W^–0.085. During the juvenile and adolescent stages (0.0047–2.9 g, 30–67 days old), M _{in vitro} /W decreased with increasing body mass following an equation M _{in vitro} /W = 1.66 W^–0.235. These results correspond with the triphasic relationship between metabolism in vivo and body mass observed in intact porgy of 0.0002–270 g (Oikawa et al. 1991). It is concluded, therefore, that the dependence of mass-specific metabolic rate on body size exists in vitro as well as in vivo, during the early stages in the porgy. Based on these results, factors controlling the metabolism-size relationship are discussed.