黄条鰤仔稚幼鱼消化酶活性变化研究

为了解黄条鰤(Seriola aureovittata)早期发育阶段的消化生理特性，测定了黄条鰤胚胎、仔稚幼鱼阶段脂肪酶、淀粉酶、胰蛋白酶和碱性磷酸酶活性变化。结果显示，在黄条鰤仔鱼出膜前胚胎阶段，即能检测到脂肪酶、淀粉酶和碱性磷酸酶活性；初孵仔鱼体内(1 d)初次检测出胰蛋白酶的活性。脂肪酶和碱性磷酸酶比活力在仔鱼孵化后迅速增强(P<0.05)，在4 d开口时，2种酶比活力达最高值；淀粉酶比活力在7 d时达最大值；胰蛋白酶比活力在仔鱼阶段缓慢上升，15 d时比活力最大。稚鱼阶段内脏团中脂肪酶、碱性磷酸酶和胰蛋白酶活性基本维持稳定，幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶活性都呈现上升趋势；稚鱼和幼鱼阶段内脏团中淀粉酶活性下降并基本稳定于较低水平。研究表明，黄条鰤仔稚幼鱼发育过程中，各种消化酶活性变化明显，且与其发育阶段和食性密切相关。在尚未摄食饵料的早期仔鱼体内已存在消化酶，认为其是母源传递而来，不是由外源性饵料所致；幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶比活力明显提高，这反映出随苗种生长发育，其肠道结构和消化机能逐渐完善，并且对脂肪、蛋白质的需求逐渐增强。     

黄条仔稚幼鱼消化酶活性变化研究

为了解黄条(Seriola aureovittata)早期发育阶段的消化生理特性,测定了黄条胚胎、仔稚幼鱼阶段脂肪酶、淀粉酶、胰蛋白酶和碱性磷酸酶活性变化。结果显示,在黄条仔鱼出膜前胚胎阶段,即能检测到脂肪酶、淀粉酶和碱性磷酸酶活性;初孵仔鱼体内(1 d)初次检测出胰蛋白酶的活性。脂肪酶和碱性磷酸酶比活力在仔鱼孵化后迅速增强(P<0.05),在4 d开口时,2种酶比活力达最高值;淀粉酶比活力在7 d时达最大值;胰蛋白酶比活力在仔鱼阶段缓慢上升,15 d时比活力最大。稚鱼阶段内脏团中脂肪酶、碱性磷酸酶和胰蛋白酶活性基本维持稳定,幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶活性都呈现上升趋势;稚鱼和幼鱼阶段内脏团中淀粉酶活性下降并基本稳定于较低水平。研究表明,黄条仔稚幼鱼发育过程中,各种消化酶活性变化明显,且与其发育阶段和食性密切相关。在尚未摄食饵料的早期仔鱼体内已存在消化酶,认为其是母源传递而来,不是由外源性饵料所致;幼鱼阶段内脏团脂肪酶、碱性磷酸酶和胰蛋白酶比活力明显提高,这反映出随苗种生长发育,其肠道结构和消化机能逐渐完善,并且对脂肪、蛋白质的需求逐渐增强。     

不同开口饵料对六斑刺鲀初孵仔鱼成活率的影响

正六斑刺鲀(Diodon holocanthus)隶属于鲀形目、二齿鲀科、刺鲀属,俗名气瓜仔、刺规等。热带海洋性底层鱼类,仔、稚鱼时期随着大洋漂游生活,成鱼后则栖息于岩礁区之浅水域,不善游泳,行动缓慢。六斑刺鲀肉质鲜美,鱼皮富含丰富的胶原蛋白,深受市场欢迎,最高时可达200～240元/千克。目前六斑刺鲀来源全部为海上捕捞,资源量也随着渔民过度捕捞呈锐减趋势。     

中华倒刺鲃仔稚鱼期消化酶及碱性磷酸酶活性变化的研究

本试验选取了中华倒刺鲃从初孵仔鱼到30日龄稚鱼，分析测定了中华倒刺鲃的特定生长率、胰蛋白酶、淀粉酶、脂肪酶和碱性磷酸酶的活性。结果表明：在整个试验期间，中华倒刺鲃的SGR为26.43%。在初孵仔鱼体内就能检测到胰蛋白酶、淀粉酶、脂肪酶和碱性磷酸酶的活性。胰蛋白酶在内源营养阶段具有较高的活性，在4日龄开口时其比活力降到一较低值，随后呈现增加的趋势，在18日龄达到最低值后又缓慢增加。淀粉酶在试验期间表现出较高的活性，比活力一直呈增加的趋势。脂肪酶在18日龄前其比活力一直增加，并且在7-18日龄表现出较高的比活力水平，18日龄后快速下降。碱性磷酸酶活性则呈现出一直增加的趋势。     

六斑刺鲀人工繁育初获成功

<正>东海水产研究所科研人员自2016年起致力于六斑刺鲀(Diodon holocanthus)人工繁育技术的探索研究。通过不断摸索,已初步掌握了六斑刺鲀亲本人工驯养的技术和方法。在对野生亲本强化营养后,于2017年6月26日获得首批约320 g受精卵,经孵化培育获得初孵仔鱼2.3万余尾。截至目前已培育平均体长(21.5±2.5)mm的仔鱼约2 100尾,仔鱼可正常摄食、生长状况良好。我所科研人员已初步掌握了六斑刺鲀亲本培育和人工育苗的技术方法。     

不同饵料组成对六斑刺纯机体代谢与免疫性能的影响

<正>六斑刺鲀(Diodon holocanthus)隶属于鲀形目、二齿鲀科、刺鲀属,俗名气瓜仔、刺规等,为热带海洋性底层鱼类,仔、稚鱼时期随着大洋漂游生活,成鱼期则栖息于岩礁区之浅水域,不善游泳,行动缓慢。六斑刺鲀为肉食性,坚硬的颌齿可咬碎贝类、棘皮动物及螃蟹等无脊椎动物为食,其肉质鲜美,鱼皮富含丰富的胶原蛋白,市场潜力巨大。目前市售六斑刺鲀来源全部为海上捕捞,已有资料证实其资源量随着渔民过度捕捞呈锐减趋势,而且其资源群体数量不稳定,具     

大泷六线鱼仔、稚、幼鱼期消化酶活力的变化

以大泷六线鱼为研究对象,研究了其从初孵仔鱼到幼鱼（0~100d）4种消化酶活力的变化。结果表明,大泷六线鱼的早期生长发育阶段4种消化酶呈现不同的变化趋势,随着鱼苗的生长发育,胃蛋白酶活力逐渐增大;胰蛋白酶活力整体呈现逐渐上升的趋势,0~30d内于20d时达到峰值后下降,40d后胰蛋白酶活力再次增大,并于60d时达到最大值;淀粉酶活力于20d时达到最大值后下降并呈现较平稳的变化;脂肪酶活力于5d达到最小值,40d后脂肪酶活力逐渐升高。     

七带石斑鱼胚胎及仔稚鱼形态观察

对七带石斑鱼胚胎和仔稚鱼发育过程进行了观察,描述了从受精卵到仔稚鱼各发育时期的形态特征;在水温22±0.5℃、盐度30条件下进行七带石斑鱼仔鱼的饥饿耐受力实验,记录了饥饿条件下初孵仔鱼的存活与生长、卵黄囊与油球的利用情况。结果表明,胚胎发育可划分为卵裂期、囊胚期、原肠胚期、神经胚期和器官形成期。在水温20.5±0.5℃、盐度30.0条件下,受精卵历时38h45min孵化出膜。初孵仔鱼全长1.059±0.071mm,至4日龄全长2.27～2.36mm时,卵黄囊完全消失;16日龄,全长4.99mm时,鳔形成;至25～30日龄,尾鳍鳍条发育完整。在饥饿条件下,初孵仔鱼的死亡高峰出现在孵化后4～6d,半数死亡时间出现在5d,至7d饥饿仔鱼全部死亡。卵黄囊期仔鱼的生长可分为3个阶段:仔鱼初孵时的快速生长期,卵黄囊消失前后的慢速生长期,以及在不能建立外源性摄食后的负生长期。随着生长发育时间的延长,饥饿仔鱼与正常条件下仔鱼的生长差异显著(P<0.05)。饥饿仔鱼体长较短,头大且体瘦,长期饥饿后脑后部下陷。     

胭脂鱼仔鱼的生长和消化酶活力变化

对胭脂鱼(Myxocyprinus asiaticus)孵化后1～37 d仔鱼的体长、体重、RNA/DNA比率、胰蛋白酶、脂肪酶和淀粉酶的酶活力变化进行了测定。结果显示:胭脂鱼仔鱼1～37 d体长稳定增长。体重增加呈阶段性,在1～21 d体重增长缓慢,21～29 d体重增加较快,29～37 d体重快速增加。仔鱼从7 d开始摄食,1～6 d,RNA/DNA比率变化很小,蛋白含量逐渐降低;7～21 d,RNA/DNA比率波动较大,蛋白含量增长缓慢;21～37 d,RNA/DNA比率和蛋白质均增长迅速。生长率(GR)与RNA/DNA比率的回归方程为:GR=1.01RNA/DNA+1.6077(R2=0.8516)。从2、5和7 d开始分别检测到明显的胰蛋白酶、脂肪酶和淀粉酶活力,之后,消化酶活力随着发育先快速地上升然后波动性地下降到一个稳定水平。结果表明:胭脂鱼仔鱼从内源性到外源性营养转化过程中,不同的消化酶能够检测到明显酶活力的时间不同,到仔鱼开始摄食时已经具备消化蛋白质、脂肪和淀粉的能力;RNA/DNA比率可以作为判定仔鱼生长率的可靠指标。     

泥鳅仔稚鱼发育期间消化酶及碱性磷酸酶比活力的变化

研究了泥鳅(Misgurnus anguillicaudatus)从孵化至30 DAH(日龄,Days after hatching)几种消化酶及碱性磷酸酶比活力的变化情况。胃蛋白酶直至30 DAH仍未检出活性。而胰蛋白酶表现出较高的比活力,其比活力在初次摄食之后显著上升,6 DAH达到最大值之后开始显著降低(P<0.05)。脂肪酶与淀粉酶的变化模式相似,在内源性营养向外源性营养转变及仔鱼向稚鱼转变这两个时间段出现两个高峰值。碱性磷酸酶比活力在2-6 DAH显著上升(P<0.05),之后开始下降并趋于平稳。研究表明,泥鳅在仔稚鱼阶段只具有结构性的胃而缺乏分泌细胞的分化。2-6 DAH是泥鳅仔鱼肠道功能迅速发育的阶段,也是向成鱼消化模式转变的一个重要过程。脂肪酶和淀粉酶比活力的持续性表明了泥鳅仔鱼对糖类和脂肪有较好的利用能力。     

Esophagoscopy and gastroscopy in dogs and cats. Technics and indications

A report is presented of esophagoscopy and gastroscopy in cats and dogs using flexible endoscopes. Following consideration of the basic equipment, an account is given of patient preparation and anesthesia, topography, investigation technique and normal findings. Diagnostic potential, indications and risks involved are discussed.     

虾蟹血淋巴的抽取与固定

随着人们对甲壳动物生理生态学研究的逐步深入,尤其是与免疫应答密切联系的血液生理学领域被广泛关注.抽取和固定血淋巴,成为进行血液学研究必不可少的步骤.那么如何更好地抽取和固定血淋巴呢,本文以虾蟹为例做了总结,以供参考.     

中国鲟鱼的保护、管理与产业化

1　世界现存鲟鱼的种类和资源鲟鱼是一类起源早、具有重要科学研究价值和极高经济价值的稀有物种 ,多数种类个体大 ,半数种为溯河洄游产卵鱼类。按目前较为公认的分类系统 ,现存鲟鱼类有 2科 6属 2 7个种 ,隶属于硬骨鱼纲、软骨硬鳞总目、鲟形目 (Acipenseriformes) ,其中鲟属有 17个种 ,主要经济种类在其中。它们全部分布于北半球 ,现存 9个自然分布区为 :太平洋东岸、北美大湖地区、大西洋西北部、北美密西西比河流域和墨西哥湾、大西洋东北部、里海地区、西伯利亚及北冰洋流域、黑龙江和日本海、长江和珠江。鲟鱼自然种群资源稀少 ,在过…     

Achieving sustainable aquaculture: Historical and current perspectives and future needs and challenges

Important operational changes that have gradually been assimilated and new approaches that are developing as part of the movement toward sustainable intensive aquaculture production systems are presented via historical, current, and future perspectives. Improved environmental and economic sustainability based on increased efficiency of production continues to be realized. As a result, aquaculture continues to reduce its carbon footprint through reduced greenhouse gas emissions. Reduced use of freshwater and land resources per unit of production, improved feed management practices as well as increased knowledge of nutrient requirements, effective feed ingredients and additives, domestication of species, and new farming practices are now being applied or evaluated. Successful expansion into culture of marine species, both off and on shore, offers the potential of substantial increases in sustainable intensive aquaculture production combined with integrative efforts to increase efficiency will principally contribute to satisfying the increasing global demand for protein and food security needs.     

Food habits and growth of silver and bighead carp in cages and ponds

Analysis of intestinal contents of silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) showed that silver carp consumed primarily phytoplankton while bighead carp consumed large quantities of zooplankton and detritus in addition to phytoplankton. The size of particles filtered by the bighead carp was larger (17–3,000 μm) than that filtered by silver carp (8–100 μm). Artificial feed was readily consumed by bighead carp but not by silver carp. No growth difference was indicated for silver carp in fertilized ponds and ponds receiving artificial feed. Growth of bighead carp increased substantially with the addition of artificial feed. Silver carp grew more rapidly in cages than bighead carp.     

虾蟹专用肥的研究开发及应用

20 0 1年 ,江苏省高邮市农林局与中国水产科学研究院淡水渔业研究中心及扬州市春申生物化工有限公司共同承担了江苏省水产更新工程项目———“虾、蟹专用肥料的开发研究与推广”。经项目组人员的共同努力 ,现已顺利完成项目任务 ,研究开发的虾、蟹专用肥在试用和大面积推广应用中取得了显著效果。虾、蟹专用肥已被列为江苏省第一批无公害水产品基地拟用鱼药、饲料推荐产品 ;也是江苏省水产技术推广站、安徽省水产技术推广站、江苏省高邮市农林局、江苏省兴化市水产局、江苏省宝应县水产局、安徽寿县水产局等十多个水产行政主管和技术推广部…     

Fish assemblage associations and thresholds with existing and projected oil and gas development

Energy development threatens fish and wildlife resources worldwide. This study used constrained ordinations to show fish assemblage structure associated with oil and gas well densities in the Colorado River Basin, Wyoming, but well densities explained only 6.4% of assemblage structure when compared to other factors. Threshold Indicator Taxonomic ANalysis showed significant negative threshold responses by some species to small levels of development (<0.15 wells km^?2), whereas positive thresholds were less distinct. Some native and imperilled species could be disproportionately affected if future oil and gas development proceeds in a manner that will impact aquatic resources. Although existing development has not substantially influenced regional fish assemblage structure, it appears to affect a subset of species. Understanding assemblage‐level responses to development can help land managers determine appropriate development levels, prioritise areas for monitoring associated with future development and identify where land protection measures may be needed to offset potential risks.     

加快城乡统筹，推进我国农垦体制创新与经济发展的研究与思考

“十一五”以来，我国农垦加快体制机制改革、结构调整和经济增长方式的转变的步伐，参与市场竞争，努力提升企业和产品竞争力，经济社会事业发展较快，对国家的贡献提升，职工收入、生活质量明显提高和改善，示范引领作用不断增强。本文针对农垦体制机制创新进展滞缓，战略定位与发展方向不明，经济增长方式转变和结构调整缺乏资本、人才、技术的支撑，没有处理好改革、发展、稳定、民生的关系，投资匮乏，发展后劲不足，人才短缺和劳动力素质低下的现状，提出在未来农垦体制机制创新中要特别关注改革方向、目标设定与评估，改革要在现行法律法规的框架内运作，改革时机的选择，处理好改革发展稳定与民生的关系，调整好内部利益分配关系，自觉融入区域经济，与地方协同发展等问题。为了促进农垦的发展，建议国家加大对农垦体制机制创新、现代农业建设、国有农场土地资源的保护、社会保障体系的完善等财政和政策的支持力度。     

Gar biology and culture: status and prospects

Many lepisosteid populations in North America have declined and many are now threatened as a consequence of habitat loss and alteration and commercial and sport overfishing. Over the last two decades, morphological, histological and molecular studies allowed distinguishing between different phases of development and the nutritional condition of larvae. Ontogeny of the digestive enzymes of gar larvae indicated the possibility to feed them artificial feeds since early developmental stages. An in vitro digestibility system to test different feed ingredients has been used. Important characteristics of artificial diets were identified through different feeding experiments. Endocrinological studies showed the feasibility of altering larval development and the digestive capacity of larvae. Cloning of gar growth hormone opened new avenues to enhance growth in the gars. Plasmatic vitellogenin was isolated and purified, to develop a competitive enzyme‐linked immunosorbent assay, which allowed the straightforward separation of males from females to establish appropriate proportions for reproduction and also was used to evaluate hormonal protocols to induce gonad recrudescence and spawning. This review analyzes the biology, ecology and physiology of different gar species as a basis for their domestication, mass production of larvae for repopulation experiments and for the culture of commercial‐size gar.