鱼苗鱼种运输技术措施

鱼苗鱼种运输是渔业生产中的重要环节，直接关系到渔业生产安全和生产效益。本文从运输工具，运输方式方法以及相关的注意事项等几方面对渔业生产中的鱼苗鱼种运输技术措施进行阐述。     

加强管理 确保鱼种安全越冬

我国北方寒冷地区,一般10月下旬结冰,翌年4月上旬解冻,冬季封冰期长达5～6个月,如何确保鱼种安全越冬?     

鱼种安全越冬措施

冬季既是水产养殖的收获季节,也是下一个养殖周期的开始。抓好鱼种管理,确保鱼种安全越冬,是鱼类养殖生产过程中的重要技术环节,应抓好以下几个方面：强化鱼种秋季培育,促进摄食,使之膘肥体壮,积蓄能量,是提高耐寒力、抗病力、成活率的一项重要措施。进入秋季后,气候、水温适宜,应多投喂一些适口性强、富含蛋白质、淀粉较多的精饲料,日投饲量为池鱼体重的3％～5％,以提高鱼种的肥满度,使之安全越冬。     

利用工程措施提高鱼种运输成活率

随着集约化网箱养鱼规模的日益扩大,鱼种运输在网箱养鱼工作中显示出越来越重要的位置。鱼种运输成活率成为制约网箱养鱼经济效益的重要环节。现在罗非鱼种运输成活率一般在８５％～９０％,有的甚至低于５０％;鲤鱼种运输成活率在９０％左右。为了提高鱼种运输成活率,...     

暗纹东方鲀鱼种冬季运输与暂养技术

暗纹东方的养殖已渐成为近年来淡水特种养殖的热点,但由于其养殖历史短暂,生产过程中的各项技术均有待于进一步完善和提高。为了配合河工厂化恒温养殖,我们于12月15日从上海币运输12万到浙中某地养殖。当时气温不到10℃,河综已人温棚越冬,经保温箱运6小时到达目的地,运输成活率达99．9％。现将其鱼种冬季运输和暂养技术总结如下：l运输前的准备11因温室建设工期受天气影响而延迟,生产单位已将鱼种转人温棚越冬,当时气温已降至10℃以内,为了便于顺利运输。先将温室养殖地加水至一半,水温调到与鱼种生产单位温棚水温一致,约门℃。…     

提高鱼种越冬成活率的有效措施

一、选好越冬池 理想的越冬池应具备以下四个条件:(1)土壤保水力强,常年不漏水。(2)水深1.7～2米(不包括冰层),底部平坦,淤泥少,无杂草和野杂鱼类。最好池底北深南浅,池上面有挡风物。(3)水源方便,水质好,便于灌水及增氧救鱼。受污染和有机物质多的水源不能利用。(4)清塘消毒,培肥水质,肥度略高于常规育种池即可。     

鱼种的初夏运输

鱼种的初夏运输由于新建池塘、改建、清淤、种青和游钓等原因，许多池塘至５月份仍需放养较大规格的鱼种。如运鱼方法不当，会造成鱼种的过多死亡。夏季鱼种运输死亡率高的原因：①此时鱼体皮肤、肌肉松驰，鱼的活动力强，运输中鳞片易脱落，容易导致水霉病等。②５月份长...     

鱼种池塘安全越冬技术措施

鱼类进入冬眠期，多潜伏在深水草丛中，很少活动，不吃食，只靠消耗体内的糖类、脂肪、蛋白质来维持生命，到来年春季出池时体重要减轻１０％～２０％。这期间，若任何一个环节失误，都会造成越冬鱼种死亡。因此，保证鱼种安全越冬是池塘养鱼生产过程中一个十分重要的环节。１越冬前的准备１．１加强秋季饲养，促进鱼种健壮为使鱼种长得又肥又壮，提高越冬成活率，进入秋季后，就要增加鱼种能量饲料的比重或添加低值的植物油（加入量为３％～５％），使饵料的脂肪量达到１０％以上为宜。一般尽可能晚停食，只要水温适宜（８℃以上），鱼类还…     

鱼种安全越冬的几条措施

一、选择合理越冬塘越冬塘应背风向阳、环境安宁、水质良好、排灌自如、管理方便。塘底平坦无渗漏,面积2亩左右,水深2m以上。二.强化追膘选大规格健壮鱼种,提前强化喂精饲料,增加鱼种体内脂肪积累,使之膘肥体胖适应越冬消耗。三、清塘施肥秋末冬初,按常规用生石灰等简易方法清塘消毒杀菌;每亩施有机肥250～500kg,以利肥水越冬。四.科学并塘选大规格无病伤的健壮鱼种进行2～3次拉网锻炼。转运井塘投放应在晴天进行,操作要小心,以免碰伤鱼体。     

河蟹养殖技术之三蟹种池养殖大规格河蟹技术

利用蟹种池进行大规格成蟹养殖,因池塘浅、存塘蟹种规格差异大、密度控制难、养殖生产迟和水草难以种植等原因,其结果往往是河蟹发病率高、出地规格小、经济效益低、经常亏本等。为搞好生产,经过实践总结,现将蟹种池养殖大规格河蟹技术介绍如下:一、暂养池的准备蟹种捕捞出售时,选择1~2个边角塘作为暂养池,面积约为蟹种地的15%,在将蟹种出售后清除池底淤泥。外塘池埂如果过低则必须加高到1.2m以上。在暂养池四周围上塑料薄膜或钙塑板,防止蟹种池在进行幼蟹捕捞时发生河蟹逃逸。将池水加注到蟹种培育时的水位线以上,2天后待穴居的小蟹洞口掘…     

海参养殖技术之四 刺参越冬保苗期管理的几点建议

刺参作为水产业的朝阳产业和北方地区养殖结构调整的重要水产品种,经济效益高,发展潜力大。但由于现在的养殖方式比较粗放,养殖工艺相对落后以及生态环境严重恶化等众多原因,刺参育苗发病率高,产苗量不稳定,此已成为该产业健康发展的制约因素之一。笔者根据几年来的     

Hormonal regulation of renal inorganic phosphate transport in the winter flounder, Pleuronectes americanus

Intestinal uptake and renal excretion are the primary determinants of inorganic phosphate (P_i) balance in teleosts. In general, teleost kidneys may either reabsorb filtered P_i or secrete excess P_i into the urine. Primary monolayer cultures of flounder (Pleuronectes americanus) renal proximal tubule epithelium (PTCs) have helped identify several hormones that may participate in conservation or excretion of P_i. Mounted in Ussing chambers, the monolayer cultures can be used to assay transepithelial P_i transport. Several factors, including metabolic acidosis, elevation of plasma [P_i], salmon stanniocalcin, salmon somatolactin and mammalian prolactin, have now been shown to alter transepithelial P_i transport in winter flounder PTCs. Salmon stanniocalcin (STC) stimulated P_i luminal-to-peritubular transport (reabsorption) at a dosage of 12.5–50 ng/ml (0.25–1.0 nM). Net P_i transport changed within 30 min and progressively increased from slight net secretion in untreated controls to net reabsorption after 3 h. The target and function of somatolactin have been uncertain. In our hands salmon somatolactin (sSL) also stimulated P_i reabsorption by flounder PTCs in a dose-dependent manner at physiological levels of the hormone (12.5 ng/ml). Net P_i transport was significantly altered by sSL within 2 h after the initial exposure. Neither sSL nor STC had any effect on transepithelial Ca²⁺ transport. The effects of both sSL and STC were mimicked by forskolin, whereas H-89, a highly specific protein kinase A inhibitor, significantly decreased the effects of the hormones as well as forskolin-induced P_i reabsorption. Furthermore, the production and release of cAMP were increased more than two-fold following exposure to STC or sSL. The data indicate that STC and sSL directly stimulate net renal P_i reabsorption by a cAMP-dependent pathway. In addition, mammalian prolactin greatly, and salmon growth hormone slightly, increased net P_i reabsorptive flux, whereas salmon prolactin had no effect. These results appear to be related to the location of the cysteine disulfide bonds within the molecular structure. Although somatolactin and stanniocalcin may both stimulate renal P_i conservation, their actions may be related to different physiological conditions.     

Modeled transport of winter flounder larvae spawned in coastal waters of the Gulf of Maine

Winter flounder, Pseudopleuronectes americanus, from southern New England and the Gulf of Maine were historically considered to be obligate estuarine spawners. However, recent experiments and observations document that winter flounder in the Gulf of Maine also utilize coastal waters for spawning. An individual‐based modeling approach was used to investigate the transport of winter flounder larvae from three hypothesized coastal spawning grounds in the Gulf of Maine. Transport success rates were greatest for larvae released from Ipswich Bay, intermediate for Stellwagen Bank and least successful for those released from Jeffreys Ledge. There was substantial interannual variability in larval transport and geographic patterns of potential connectivity. Furthermore, the date of spawning had an important influence on transport success. Model results suggest that certain coastal spawning grounds used by winter flounder may serve as an important source of larvae to estuaries and nearshore nursery areas. The potential influx of coastal spawned larvae could have implications for the resilience, productivity and gene flow in local populations. Model results provide further support for the conclusion that winter flounder in the Gulf of Maine may not be solely dependent upon estuaries for spawning. Results also suggest that coastal spawning groups should be considered explicitly in the management of winter flounder, and protected under Essential Fish Habitat regulations.     

中国鲷科鱼类分类和系统发育研究进展

为研究黑鲷(Sparus inacrocephalus)增殖放流最适宜运输密度及运输后生理生化变化情况,选取全长9~11.7 cm的黑鲷鱼苗为实验对象,设计5个密度组(10尾、15尾、20尾、25尾和30尾)采用塑料袋密封充氧运输方式,即塑料袋中充等量的海水并充氧至饱和,水体为育苗池海水,水温27.7 ℃,盐度29,pH 8.04,溶解氧8.8 mg·L^–1,运输2.75 h。分别于运输后暂养的第0、第6、第12、第24和第48小时取样,研究黑鲷鱼苗血清和肌肉中总蛋白(TP)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、丙二醛(MDA)等指标的变化情况。结果显示,不同密度的塑料袋密封充氧运输后,10尾组和15尾组血清和肌肉中的TP和MDA浓度低于30尾组(P<0.05),而SOD和CAT活性显著高于30尾组(P<0.05);从暂养后恢复水平上看,10尾组和15尾组肌肉和血清中各项指标恢复最快,20尾组和25尾组次之,30尾组的各项指标恢复较慢且至实验结束时未能全部恢复。综合经济因素分析,在水温27.7 ℃、盐度29、pH 8.04的条件下运输9~11.7 cm黑鲷鱼苗2.75 h时,用塑料袋密封充氧运输的最佳密度为每袋25尾。     

Physical oceanography of the North Carolina continental shelf during the fall and winter seasons: implications for the transport of larval menhaden

The circulation over the continental shelf off the southern Middle Atlantic Bight (MAB) and northern South Atlantic Bight (SAB) is examined for the fall and winter periods. Observational data are compared with results from a three-dimensional numerical model to identify the dominant processes on the shelf. By considering wind-forcing, tides, and a specified upstream inflow (into the MAB), the observed and modelled flow fields are in close agreement in the mid- and inner shelf regions. The resulting larval drift indicates a seasonal dependence of transport pathways from spawning grounds to estuarine nursery areas for menhaden larvae and other offshore-spawning estuarine-dependent fish. Specifically, the physical oceanography of the MAB and SAB during the fall and winter months suggests a north-to-south shift in spawning areas providing recruits to the Carolina estuaries, in agreement with the observed migration of the spawning populations.     

Physical oceanography of the North Carolina continental shelf during the fall and winter seasons: implications for the transport of larval menhaden

The circulation over the continental shelf off the southern Middle Atlantic Bight (MAB) and northern South Atlantic Bight (SAB) is examined for the fall and winter periods. Observational data are compared with results from a three-dimensional numerical model to identify the dominant processes on the shelf. By considering wind-forcing, tides, and a specified upstream inflow (into the MAB), the observed and modelled flow fields are in close agreement in the mid- and inner shelf regions. The resulting larval drift indicates a seasonal dependence of transport pathways from spawning grounds to estuarine nursery areas for menhaden larvae and other offshore-spawning estuarine-dependent fish. Specifically, the physical oceanography of the MAB and SAB during the fall and winter months suggests a north-to-south shift in spawning areas providing recruits to the Carolina estuaries, in agreement with the observed migration of the spawning populations.     

鱼虾蟹越冬管理技术之四:冬季鱼塘补氧技术

冬季天气寒冷,水温低,鱼类主要集中于池水底层,由于耗氧量增加,易造成底层水体缺氧,使鱼类窒息死亡,降低养殖成活率.下面介绍几种鱼池冬季补氧的办法.     

冬季池塘管理的误区及应对措施

<正>进入严冬季节,有的养殖户思想麻痹、高枕无忧,有的养殖户疏于管理、操作不当,有的养殖户缺乏认知、盲目乐观,极易给冬季池塘管理带来一定影响,造成经济损失。因此,加强冬季池塘管理刻不容缓。笔者结合日常在一线工作实际,提出如下应对措施,仅供广大养殖户参考。一、冬季池塘管理的误区误区一:有的养殖户认为,冬季气温变化幅度较大,水温变化幅度较小,池塘水深、水浅不重要。实践证明,越冬池塘适当水深至关重要,直接关系到越冬水产养殖动物的活动和存亡,     

冬季跨海区暂养扇贝苗种技术探讨

海阳市地处山东半岛西南部,南濒黄海,地理座标36°15′—37°10′N,120°50′—121°28′E。海区水温变化相对稳定,每年低温时间短,在1月份水温最低,一般在3℃左右;春季水温回升早,到2月份水温就回升到5℃左右,不利于扇贝苗种生长的低温期仅50天左右。