深水网箱养殖鱼类的分级与起捕技术

鱼类的规格分选与起捕销售是网箱养殖生产中的重要环节.以往的手工操作不仅费时、费力,而且由于鱼类转移速度缓慢以及操作过程中对鱼体的损伤和对鱼群的惊吓等,还会带来较高的死亡率.随着我国大型深水抗风浪网箱养殖的发展,这一问题日显突出.本文介绍了国外几种典型深水网箱养殖鱼类的大小分级与起捕的方法,总结我国大型深水网箱养殖鱼类分级与起捕设备的研究进展.研制的柔性格栅式分级装置不仅具有可折叠、操作方便和不损伤鱼体等特点,而且通过更换不同间隙的分离栅,可实现鱼类大小的多级分离.海上分级试验表明,经10min分级,允许逃逸的小个体鱼类的平均分离率可达90.3%;研制的真空活鱼起捕机可实现鱼类的快速转移,最大起捕个体可达1.5kg,且对鱼体无损伤,在鱼水比例为1:1的情况下,活鱼起捕量可达20t/h.     

舟山市普陀区开展深水网箱养殖初试效果显著

浙江省舟山市普陀区从挪威引进全省第一家深水网箱养殖设备，自２０００年９月２２日正式投产以来，到２００１年４月２９日全部起捕换箱或移鱼为止，历时７个月零７天。致此深水网箱第一阶段试养暂告段落。通过对该阶段深水网箱试养情况观察，养殖鱼类起捕综合检查与对照组小网箱养殖测量比较，深水网箱养鱼初步显示出优势，同时也存在一些问题。现将本阶段试养情况小结如下： 一、优势方面： １．鱼类生产快。如孙明康单位放养的美国红鱼、免状黄姑鱼、真鲷三种鱼类，其中美国红鱼９７６０尾，鱼种均重２２０９，到４月 １７日起捕检查时…     

网箱吸鱼泵的研制和试验

1概述近年来网箱养殖业发展迅速 ,浙江省网箱养殖的发展速度和力度处在全国的前列。无论是近海的传统形式的网箱 ,还是从国外引进的大型深水网箱 ,或是在国外网箱基础上国产化的深水网箱及新开发的升降式碟型网箱 ,都已在全省渔区逐步推广应用。但是 ,与网箱养殖配套的起鱼捕捞设备、鱼货分级处理装置等 ,在国内目前还是空白。网箱养殖在收获鱼货或鱼类分箱养殖时 ,都是用小网兜人工起捕。特别是收鱼出售时 ,数量多时间紧 ,而人工起捕速度慢、时间长影响鲜度 ,且劳动强度大 ,迫切要求开发吸鱼泵等装置。2国内外吸鱼泵研究现状和发展趋势国外…     

论深水网箱鱼类养殖技术

深水网箱养殖是我国新兴的海水鱼类养殖方法。通过2001～2004 年的养殖试验和生产实践,在深水网箱国产化和工程技术研究等方面已经取得了突破,网箱抗风浪性能优良,已能在有屏障的半开放海区抵御12 级以上的强台风,但在深水网箱鱼类养殖技术上还存在许多问题,加强这方面的研究是深水网箱养殖业的当务之急,本文就深水网箱鱼类养殖技术进行了全面探讨。     

深水网箱养殖病害综合防治技术

深水网箱养殖因集约化程度高、养殖密度大、单位水体产量高、产品质量高和经济效益显著等特点而备受瞩目。然而随着养殖生产的发展，深水网箱养殖的鱼类也出现了病害。根据2003年浙江省水产病害测报信息，部分地区深水网箱养殖的大黄鱼已不同程度地发生了细菌性疾病和寄生虫病，虽然对养殖生产造成的影响和损失并不大，但已经为深水网箱养殖的病害防治敲响了警钟。     

试论浙江省深水网箱养殖产业的发展

深水网箱养殖是在投饵条件下进行的高密度、大规格、当年放养当年起捕或者当年放养隔年起捕的一种精养高产养殖方式,经过几年的培育发展,已初步体现出巨大的经济和社会效益.持续发展深水网箱产业作为设施渔业的新型生产力,已成为继续深化渔业结构调整的一项重要举措,因此各级政府和渔业主管部门在制定政策、落实措施的同时,更应该具备"站在月球看地球"的战略眼光,确立全面、协调和可持续的科学发展观,放开手脚,以市场的理性竞争来自然调节深水网箱的"总量控制",在统筹浙江山海资源优势的基础上,进一步加强宏观调控,将深水网箱养殖产业培育成为浙江渔业支柱产业.     

南麂海区深水网箱适养鱼种初步筛选

深水网箱作为一种新型的海水鱼类养殖设施，已在我国沿海渔区逐步推广。然而，各地的产业化实践表明，如何找到若干种既能适合当地海区养殖，又能适销的深水网箱养殖鱼类品种，已成为决定深水网箱养殖成败的关键之一。挪威经过10年多的探索研究，终于成功实现大西洋鲑(三文鱼)的网箱养殖，取得了巨大的商业利润。为此，我们专门在南麂海区开展了深水网箱适养鱼种筛选试验，从分析养殖水域的生态环境特点着     

深水抗风浪网箱的日常管理与维护

近年来 ,我国深水网箱养殖发展较快 ,大型深水抗风浪网箱以其容积大、养殖鱼类成活率高、回报高的优势逐渐得到广大养殖业者的青睐。深水抗风浪网箱因其放置于离岸较远的深水区域 ,距管理区较远 ,给管理和维护带来不便。为了避免因箱体网衣破损、部件损坏而导致养殖鱼类逃逸等现象的发生 ,使用单位在使用网箱过程中对其进行必要的维护是十分必要的。本文就深水抗风浪网箱的使用和维护提出若干建议 ,供广大养殖者参考。1深水抗风浪网箱的组成和特点深水抗风浪网箱主要由框架系统、网囊、固定系统和配套设施组成。利用固定平台与箱体的相互作…     

浙南浅海鱼类养殖概况及渔业统计的探讨

正浅海鱼类养殖不但是海水养殖的重要组成部分,而且由于浅海鱼类养殖的开放性,其对海洋环境和资源也有重要的影响。按渔业统计要求,普通网箱养殖面积以平方米计,深水网箱养殖面积以立方米计,由于统计人员对普通网箱和深水网箱区分界限模糊,统计数据往往与实际情况相差较大,不能很好地为养殖生产指导和决策提供真实依据。为了摸清浙江南部温州海水鱼类浅海养殖的真实情况,浙江省海洋水产养殖研究所对浙南温州的浅海     

膨化饲料网箱养殖中华鳖试验

网箱养殖由于产量高,便于管理,易于起捕,单位效益好而常用于鱼类养殖,中华鳖养殖一般多见于温室工厂化养殖和池塘生态养殖。为探索新的养殖模式,给农民带来新的经济增长点,充分利用江南水乡的资源优势,我们于2011年5月与浙江省嘉兴市王江泾镇双桥村吴荣华联合进行膨化料网箱养殖中华鳖试     

Estimation of variation of virulence of Renibacterium salmoninarum by survival analysis of experimental infection of salmonid fish

The variation of virulence of Renibacterium salmoninarum , the causative agent of bacterial kidney disease (BKD) in salmonid fish, was studied by infecting rainbow trout, Oncorhynchus mykiss (Walbaum), with two isolates (strains 325 and 932) from diseased Atlantic salmon, Salmo salar L., and one isolate (strain 4366) from an apparently healthy Atlantic salmon. Coho salmon, Oncorhynchus kisutch (Walbaum), were injected with the strain 932 to estimate difference in fish species resistance. Fish were removed by random sampling for other study purposes, a study design possible with analysis of lifetime distributions incorporating both sampling-, death- and survival-times. At the end of the experiment, the rainbow trout infected with strains 325, 932 and 4366 had a survival probability of 33%, 51% and 72%, respectively. The coho salmon infected with strain 932 had a 26% survival probability. The strain differences were significant according to the log-rank test, and the risk ratio between the strains ranged from 1·8 to 5·4. The strain from the apparently healthy fish was least virulent. The survival of the fish species was different over time. Rainbow trout were more likely to die early in the time course, but high numbers of coho died later, resulting in an overall risk of mortality of 1·4 in favour of rainbow trout. Differences in virulence may reflect changed selective pressure on R. salmoninarum when introduced from feral stocks into the environment of fish farms.     

母猪胎衣不下的病因与防治要点

猪的胎盘属于弥散型胎盘,这种胎盘的结构特点和饲养管理的不当,常常导致母猪胎衣不下发生,给生猪的生产繁殖带来极大损失。本文针对母猪胎衣不下发生病因、综合防治进行详细阐述,旨在对预防和治疗胎衣不下能有所帮助。     

水硬度对七彩神仙鱼幼鱼发育的影响

采用不同硬度的水对七彩神仙鱼幼鱼进行饲养。6周龄幼鱼在硬度为7.94°dH±0.30°dH时饲养84d后,比在硬度为14.71°dH±0.23°dH水中的幼鱼个体大,生长速度快。表明较高硬度的水有利于七彩神仙鱼幼鱼的生长发育。     

虎斑乌贼受精卵卵黄营养成分分析

本实验对虎斑乌贼受精卵卵黄的营养成分进行分析,旨在探讨其幼体的营养需求量,为其幼体配合饲料研制提供参考数据。随机选取大约800个虎斑乌贼受精卵的卵黄,采用国家标准方法测定其水分、灰分、粗蛋白质、粗脂肪、氨基酸、脂肪酸和矿物元素含量。结果表明:1)虎斑乌贼受精卵卵黄中粗蛋白质含量为76.33%(干重基础);总氨基酸(TAA)和必需氨基酸(EAA)含量分别为71.22%和32.38%(干重基础),EAA/TAA为45.46%,氨基酸中以谷氨酸(Glu)含量最高(9.97%),必需氨基酸中亮氨酸(Leu)含量最高(7.58%)。2)其粗脂肪含量12.71%(干重基础);共检出17种脂肪酸,包括8种饱和脂肪酸(SFA)、5种单不饱和脂肪酸(MUFA)和4种多不饱和脂肪酸(PUFA),SFA、MUFA和PUFA分别占脂肪酸总量的43.47%、7.54%和49.25%,其中以DHA含量最高,达32.80%,EPA含量为7.70%,DHA/EPA为4.26。3)检测出Na、K、Ca、Mg、Sr、Mn、Fe、Cu、Zn、Al和As 矿物元素,微量元素中富含Zn、Al和Fe,含量分别为 0.77、0.71和0.43 mg/kg(鲜重基础)。由此可见,卵黄具有高蛋白、低脂肪,富含n-3PUFA的特点;虎斑乌贼幼体饲料中蛋白质需求量参考值为76.33%;氨基酸需求量参考值,如赖氨酸(Lys)为5.49%,蛋氨酸(Met)为2.63%;脂肪的需求量参考值为12.71%,DHA为4.17%,EPA为0.98%;微量元素需求量参考值,如Zn为2.77 mg/kg,Cu为0.19 mg/kg(干重基础)。     

Characterization of protease inhibitors of seminal plasma of cyprinids

Anti-proteinase activity was demonstrated in the seminal plasma of cyprinid fish species (bream, chub, ide, dace, asp, goldfish, roach, common carp) using electrophoretic techniques combined with a detection method based on inhibition of bovine trypsin. We found species-specific protease inhibitors in the seminal plasma of cyprinids. At least three bands of protease inhibitors with different migration rates could be identified by native PAGE. Higher variability was characterized for bands with slower migration rates. Visualization of inhibitors after SDS-PAGE under non-reducing conditions allowed estimation of their molecular weights. Apparent molecular weights were within the range of 51–59 and 47–54 kDa for the bands with slower and moderate migration rates, respectively. The molecular weight of fast migration bands for roach and common carp were estimated to 23 and 30 kDa, respectively. Inhibitors of common carp seminal plasma differed in their affinity toward serine proteases. Three inhibitors in common carp seminal plasma could be visualized using cod and bovine trypsin, but only two inhibitors (of high molecular weight) were recognized with chymotrypsin. There were differences in anti-proteinase activity and seminal plasma protein concentration in relation to the origin of common carp seminal plasma (breeding lines) and time of milt collection (spawning vs. post-spawning season).     

鱼类热忍耐温度研究进展

The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect: (1) The key parameters of temperature of thermal tolerance in fishes; (2) The influence factors of temperature of thermal tolerance in fishes; (3) The research methods of thermal effect of fishes; (4) The evaluation of effects of thermal pollution on fishes, especially, with the coastal power station will be‘built in China recent years, the effects of thermal discharge water on the marine fisheries resource wered iscussed.     

Histopathology of respiratory organs of certain air-breathing fishes of India

Air-breathing fishes have evolved bimodal respiratory mechanisms for exploitation of water (through gills and highly vascularized skin) as well as atmospheric air (through aerial respiratory organs, ABO). Mucous cells in these respiratory organs of variously stressed fishes exhibit periodic fluctuations in their density and staining properties. The main types of damage in the gills include congestion of blood capillaries (BLCs), periodic lifting and sloughing of respiratory epithelia of the secondary lamellae causing haemorrhage, extensive fusion of secondary lamellae and hyperplasia of the respiratory epithelia due to uncontrolled regeneration leading to asphyxiation, altered excretion, and death of the fish. Haemolysis has also been observed following lead exposure. The damage in the ABO of Heteropneustes fossilis includes sloughing of the epithelial cells, leading to haemorrhage causing decreased red blood corpuscles density and degeneration of the secondary gill lamellae with reduced respiratory area. Subsequent hyperplasia of the respiratory epithelia and fusion of gill lamellae increase the respiratory barrier distance. The BLCs often bulge out and protrude into the lumen, bringing blood nearer to air. The ladder-like pillar cell (PLC)-BLC components of the gill lamellae frequently collapse. Damage to the ABO of Channa striata is less severe. Often haemorrhaging due to bursting of extensively stretched BLCs causes aerial respiratory failure. Chloride cells of the ABOs also show hyperplasia. While the highly mucogenic epidermis of C. striata shows less damage, the epidermis of Clarias batrachus and H. fossilis shows severe wear and tear, sloughing, and haemorrhage. Side-by-side regeneration continues, causing altered histomorphology of the epidermis. The different gland cells also show periodic fluctuations in their density and staining. The dermis also shows severe damage with loosening of their connective tissue fibres. These fibres give stronger reactions for sulfated mucin that not only retain additional water molecules for continuance of skin breathing, but also bind the toxic ambient pollutants.     

牙鲆刺激隐核虫病的防治

2005年七、八月份,乐亭、滦南一带多家工厂化牙鲆养殖场发生刺激隐核虫病,此种病虫害发病急、传染快、死亡率高。发生过该病的养殖场牙鲆死亡率一般都在50％～80％之间,这种病害给牙鲆养殖业带来很大损失。     

浅谈船舶干舷的作用

近几年．在唐山沿海发生的渔船海难、海损事故经统计表明呈增多趋势。这与出海作业渔民的安全意识不强有很大关系．渔民为了挣取更多的效益，在海上，超抗风浪等级作业且人为地增加船的不规范载荷．造成船的储备浮力损失，酿成恶果。笔者认为．在渔船设计建造中，留取的干舷对渔船作业的安全性起相当重要的作用，必不可少。 一、储备浮力的重要性 所谓储备浮力就是自船舶设计水线至水密甲板的水密部分体积，其大小与干舷相关．于舷大则储备浮力大，干舷的重要性就在于能够使船在海中保持正常的浮性和安全。再者，在设计建造渔船时，为了改善…     

脂质体介导的鲫CAB细胞转化及转化细胞的核移植

采用脂质体法成功地使gfp基因转入鲫囊胚细胞株CAB细胞基因组，获得了具有G418抗性的细胞。以转化细胞为供体，银鲫卵为受体，核移植得到了转基因的囊胚和原肠胚；并发现4℃处理细胞24h能显著改善核移植胚胎的发育。