三月份甲鱼养殖的操作重点

室内养殖：阳春三月，气候渐暖，晴天时要敞开温棚门窗，让空气流通。室外养殖：春天雨水多，乍暖还寒，越冬池的“保暖”仍很重要。三月份温度变化很大，而且水温又是在甲鱼结束冬眠的临界点，甲鱼会因水温升高而结束冬眠，又会因温度降低而沉入池底，此时正是越冬甲鱼经历漫长的越冬期后体质量弱的时候，容易因环境不良而致病死亡。本月应注意春季甲鱼越冬后期的死亡问题。三月份甲鱼养殖的操作重点     

室内外综合养甲鱼快速育肥技术

室内外综合养甲鱼快速育肥技术辽东甲鱼养殖技术培训中心甲鱼养殖试验场，近二年来探索出一套甲鱼快速育肥技术，将七、八月份孵化出的３～５克稚甲鱼移入人工控温工厂化养殖厂房稚甲鱼培育池进行越冬培育，体重达到１００克左右，在第二年５月份移到室外上池或鱼池进行人...     

西北地区养殖甲鱼越冬死亡原因分析与预防

我国西北地区冬季气温偏低,池塘封冻与甲鱼冬眠期较长,人工养殖甲鱼在每年越冬期间均出现体质衰弱及大量死亡现象,笔者分析养殖甲鱼越冬死亡的原因,并总结预防措施如下,以供同行借鉴。 一、甲鱼越冬死亡原因分析 1.水质原因 一方面,池塘封冻时间过长,水体与空气接触     

室内外结合养甲鱼

辽宁省辽东甲鱼养殖技术培训中心甲鱼养殖试验场近两年来探索出一套北方地区甲鱼快速育肥技术,将7、8月份产卵孵化出的3—5克稚甲鱼移入人工控温工厂化养殖厂房稚申鱼培育地进行越冬培育,体重达到100克左右,在第二年5月份移到室外土池或鱼池进行人工饲养,经过18个月的时间(其中有7个月是越冬休眠不活动期)雄甲鱼平均体重达到750克,雌甲鱼平均体重达到550克。     

第一讲甲鱼人工养殖概况及其养殖生物学特性

为了配合当前甲鱼养殖生产,普及推广甲鱼养殖技术,本刊从本期起,邀请国内知名甲鱼养殖专家王宾贤先生撰写《甲鱼人工养殖技术》系列讲座,拟在本刊1996年1-6期依下述题目刊出:一、甲鱼人工养殖概况及其养殖生物学特性;二、甲鱼的繁殖及其人工孵化技术;三、甲鱼的越冬育种及其商品养殖;四、甲鱼的营养需要及解决饲料的途径;五、甲鱼的病害及其防治技术措施;六、甲鱼养殖生产的经营技艺。以飨读者。     

滆湖甲鱼生态高效养殖技术

介绍了在草型浅水湖泊滆湖中进行甲鱼生态高效养殖的技术,包括湖泊中甲鱼生态养殖基地的选择标准、养殖模式及养殖设施、鳖种的放养、日常管理、越冬管理、捕捞及运输等。     

应用地热水高密度饲养稚甲的越冬试验

人工养殖甲鱼的中心问题是缩短养殖周期，达到高产，高效的目的。在常温饲养条件下，每年夏秋季孵化脱壳的稚甲鱼，其个体重量仅为4-5克，且不久即进入半年以上的冬眠，越冬期间死亡率很高，据资料介绍：在自然条件下饲养的稚甲鱼，越冬成活率大约为20-30％；而且体重下降5-10％；要经过二年饲养才能达到50克左右。     

温室甲鱼无公害健康养殖及主要疾病控制技术

甲鱼温室养殖是整个甲鱼养殖生产中的一个重要阶段，它具有密度高、投饵集中、水质易污染和病害多等特点，因此，做好甲鱼的温室养殖工作对提高整个甲鱼养殖的经济效益具有举足轻重的作用。现将甲鱼温室无公害健康养殖及主要疾病控制技术介绍如下：     

健康养殖专栏

患红脖子病的甲鱼如何安全越冬１１月份在自然状态下，甲鱼已停止摄食，并开始进入冬眠，如果甲鱼得红脖子病后置于越冬池中，甲鱼已没有摄食能力。因此，此时治疗甲鱼红脖子病只有两种措施：一是将甲鱼挪进室内，将水温逐渐提升到２５℃以上，用“佳纬牌”甲鱼全价配合饲料，加入“鳖健康”１．５％和“鳖健康２号”０．５％制成药饵投喂，一周内炎症就会消失。继续用“佳纬牌”甲鱼全价配合饲料并加入０．３％的“水产专用ＶＣ”，做成药饵投喂，甲鱼将彻底痊愈。然后逐渐降温，移至室外越冬，进越冬池前，需用“鳖净”０．４ｍｇ／Ｌ药浴…     

甲鱼越冬并塘技术

深秋是商品甲鱼收获的季节。尤其对工厂化养殖来讲,商品甲鱼不能在短期内销售完,为了便于管理和甲鱼的安全越冬,越冬并塘在每年的10月—11月份进行。现介绍一下甲鱼越冬并塘的技术要点。1 调整好甲鱼越冬塘的底质和水质 甲鱼是变温动物,其活动规律和栖息环境随季节、温度的变化而异。严寒的冬季来临之际,甲鱼即潜入水底泥沙或洞穴中。一般水温降至15℃时,甲鱼即停食,开始寻找适合其安     

不同饲养方式对肉鸡生产性能的影响

选择1日龄罗斯308肉鸡12000只随机分为3组,在相同营养条件和饲养管理程序下,分别进行笼养、地面平养、棚架饲养,研究了3种饲养方式对肉鸡生产性能的影响。试验结果表明:49日龄时肉鸡体重笼养最高,其次是地面平养,棚架饲养最低,分别为2.6kg、2.5kg、2.4kg;肉鸡的料肉比笼养最低,其次是棚架笼养,地面平养最高;腿病的发生率笼养最高,其次是棚架饲养,地面平养最低;肉鸡出栏率笼养最高,其次是棚架饲养,地面平养的肉鸡出栏率最低。综上所述,笼养和棚架饲养与地面平养相比,能提高肉鸡增重和出栏率,降低料肉比。     

Estimation of flow in a rearing tank of marine fish larvae by simplified numerical computation—a case of two-dimensional flow

Marine fish larvae are fragile against physical stress. However, few studies have been conducted to evaluate the flow field in a rearing tank, which is assumed to provide a high degree of physical stress to marine fish larvae. The flow field in a rearing tank (volume of 1 m³) is generated by aerators, which are commonly used to provide oxygen.

This paper is a report on the estimation of stationary flow in the rearing tank of marine fish larvae. The larvae are seven band grouper larvae of Epinephelus septemfasciatus, which have a very low survival rate immediately after the hatching of eggs. The experiments of rearing of seven band grouper larvae were carried out using rearing tanks with four aeration rates (1000, 200, 50 ml/min, and no aeration). The effects of aeration on the survival and floating death of seven band grouper larvae were examined. The experiments confirmed that the mass mortality of seven band grouper larvae depends on the flow rate in the rearing tank. Aeration at 200 ml/min resulted in the highest survival and growth rates of grouper larvae.

Larvae-rearing experiments provided evidence that the flow rates of the rearing tanks are very important design aspects of rearing tanks. The estimation of flow in a rearing tank for an aerating rate of 200 ml/min was carried out by numerical calculation. The computation was simplified by a two-dimensional flow based on experimental results. The calculated flow in the rearing tank was compared with the experimental one. The calculation of the stationary flow in the rearing tank showed good qualitative and quantitative agreement with the experimental results. The numerical estimation of the flow in a rearing tank of marine fish larvae was confirmed to be effective and satisfactory for the design of a tank that would provide optimum performance.     

中华仙影海葵亲体驯养的初步试验

报道了中华仙影海葵亲体驯养的方法和实验培养的初步结果,描述了海葵亲体驯养的条件和管理方法,对饵料投喂和产卵规律进行了探讨,提出了中华仙影海葵亲体驯养的技术要点。     

微生态制剂对提高漠斑牙鲆育苗成活率的作用

对漠斑牙鲆育苗过程中添加微生态制剂以提高育苗成活率进行了比对实验。结果表明:采用育苗水体中添加微生态制剂的方法,能明显提高漠斑牙鲆育苗的成活率,改善水质,降低育苗用水量约30%~40%。在初孵仔鱼1×104ind/m3密度的条件下,添加微生态制剂的育苗池中不同阶段的仔稚鱼成活率高于对照组5%~10%;但随密度增加至2×104ind/m3时,实验组和对照组相互殘杀增加,仔稚鱼成活率都呈下降趋势;密度增加至3×104ind/m3时,实验组与对照组之间差异不显著(P<0.05)。     

Influence of rearing conditions on Flavobacterium columnare infection of rainbow trout, Oncorhynchus mykiss (Walbaum)

The influence of rearing conditions on Flavobacterium columnare infection of rainbow trout, Oncorhynchus mykiss (Walbaum), was studied experimentally in the laboratory and at a fish farm. In experiment I, the effect of parasitic infection on columnaris disease was studied using F. columnare carrier fish. The fish were exposed to Diplostomum spathaceum cercariae and a set of other stressors in order to induce clinical columnaris infection. Parasitic infection and other stressors failed to induce the disease. Disease occurred when the fish were challenged with F. columnare, but D. spathaceum infection did not enhance the severity of the infection. In experiment II, the influence of rearing density and water temperature was studied. Overall mortality was highest in fish at normal rearing density with high temperature (+23 degrees C). At low temperature (+18 degrees C) mortality was not affected by rearing density, but the transmission of columnaris disease was faster at normal rearing density at both temperatures. This supports the view that reduction of fish density could be used in prevention of columnaris disease especially if water temperature is high. Because the lower rearing density can also decrease the transmission of ectoparasites and penetrating endoparasites, it could be an efficient tool in ecological disease management.     

水库小网箱养鲤效果及其与密度的关系

在３５０、４００、４５０、５００尾／ｍ２的放养密度下,研究了小网箱养鲤效果。结果表明,小网箱放养密度对净产量有极显著的影响,最佳放养密度为４７３尾／ｍ２,随密度增加,出箱鲤鱼的平均体重和生长比速下降。与大网箱相比,小网箱在饲料系数、效益指数等方面具有显著优越性。     

Response changes with growth in the gustatory receptors of young yellowtails (Seriola quinqueradiata)

SUMMARY: Laboratory-hatched juvenile yellowtails (mean fork length, 9.3 cm) were reared for 2 months in two groups on different kinds of food, mysid and squid in one group and fish in the other, and the gustatory neural responses to seven chemicals (adenosine-5'-monophosphate, alanine, arginine, betaine, proline, tryptophan, and valine) were recorded in fish before and after the 2-month rearing period. Large variances in the responses to some chemicals were noticed in the juveniles before the rearing experiment. Mann–Whitney U -tests on the neural responses indicated significant changes in the magnitude of the responses to valine and some other chemicals relative to that for proline or tryptophan between the pre- and the two post-rearing groups. No significant differences in the response magnitude for the seven chemicals were observed for the two post-rearing groups suggesting that the response changes during the 2-month rearing might have been intrinsic and not due to specific food items in the diet. The dose–response relationship for some chemicals was also examined in the juveniles before and after the 2-month rearing. A slight lowering of threshold was noticed for alanine and valine after the rearing. Data on the responses of wild yellowtails were in support of the changing responsiveness of gustatory receptors during development of juvenile yellowtails.     

海带工厂化低温育苗法及其科学技术基础

海带工厂化低温育苗是一项综合性技术措施,其中心环节是海带的“夏繁”和配子体、幼孢子体的“越夏”。围绕着这二个中心环节,试验研究取得了夏熟种海带培育、集约式平面采光、人工附着基的改进和制作、育苗期间的温光控制和制冷工艺、病害防治、以及水的循环与净化等配套技术和成果,有效地促进了海带养殖业的发展。本试验根据海带生物学特性,以人工模拟的环境条件,结合考虑经济上的合理性,培育出大量幼苗,这对海洋及内陆水域中其他生物资源的开发利用提供了有参考价值的途径。     

塘鳢的养殖试验

塘鳢是淡水小型经济鱼类，江浙沪一带将其视为名菜，为发展特种小水产品，作者于１９９２～１９９５年进行了塘鳢养殖试验工作，取得了人工繁殖，苗种培育及成鱼饲养的成套经验，人工繁殖和苗种培育在２０ｍ＾２的网箱中进行，鱼孵化率和苗种（夏花）成活率分别达到５９．７１％和７１．０３％，成鱼饲养采取池塘混养方式，在２６７ｍ＾２的池塘中经１７０天养成尾重２０ｇ以上的商品鱼１８．２５ｋｇ，成鱼饲养成活率为６４．５％     

罗氏沼虾早繁苗中间培育及商品虾两茬养殖技术探讨

在上海地区进行罗氏沼虾商品虾两茬养殖，关键是抓好早繁苗的中间培育和第二茬养殖用苗的囤养。采用温室保温、锅炉增温和气泵充气等技术措施对罗氏沼虾的早繁苗进行集约化中间培育，可以提前１个月，在５月１０日左右为商品虾的第一茬养殖培育出大规格虾苗。利用室外土池囤养晚苗，为第二茬养殖培育虾苗，重点应处理好饲料投喂与水质调节之间的矛盾。