2003年春季东海区浮性鱼卵和仔稚鱼种类组成及数量分布

本文分析研究了2003年春季东海区(27°00′～34°00′N)150m以浅海域浮性鱼卵、仔稚鱼的种类组成及数量分布。共鉴定49种鱼类的鱼卵、仔稚鱼,其中31种鉴定到种,隶属于26科、29属。优势种类为日本鳀、方氏云鳚、太平洋鲱。带鱼、小黄鱼等经济鱼类鱼卵、仔稚鱼数量少,鲱形目鱼类鱼卵、仔稚鱼数量较多。鱼卵、仔稚鱼分布主要在近海禁渔线附近海域。     

罗源湾夏季鱼卵和仔稚鱼种类组成与数量分布

分析研究了2009年7月福建罗源湾鱼卵、仔稚鱼的种类组成及数量分布。共鉴定19种鱼类的鱼卵和仔稚鱼,隶属于13科。其中,鱼卵10种、仔稚鱼14种。夏季,罗源湾水平拖网鱼卵和仔稚鱼平均密度分别为1.80 ind/m3和0.54 ind/m3;垂直拖网鱼卵和仔稚鱼平均密度分别为4.11 ind/m3和2.63 ind/m3。鱼卵、仔稚鱼以鳀科数量最多,优势种类为中颌棱鳀(Thrissa mystax)和康氏小公鱼(Stolephoruscommersonli)。与历史资料相比,不但种类数减少,且优势种由多科鱼类并存向鳀科鱼类为主转变。夏季鱼卵、仔稚鱼主要分布在罗源湾中北部海域及湾口附近。     

福建诏安湾春、秋季鱼卵和仔稚鱼种类组成及数量变化

2012年10月和2014年5月在诏安湾海域进行了鱼卵、仔稚鱼的调查,对诏安湾秋季和春季的鱼卵和仔稚鱼的种类组成、数量和分布进行了研究。结果表明,本调查海域共鉴定的鱼卵7种、仔稚鱼7种,隶属于10科10属;秋季共采集到鱼卵31个和仔稚鱼47尾,密集区出现在湾口的西屿北侧海域,春季共采集到鱼卵662个和仔稚鱼69尾,密集区主要分布在诏安湾中部偏北海域和湾口西屿西侧海域。秋季主要优势种为隆头鱼科鱼类、美肩鳃鳚,春季主要优势种为黄姑鱼、红鳍笛鲷和美肩鳃鳚。与东山湾相比,春季诏安湾鱼卵密度明显较大、仔稚鱼资源密度略低;秋季两个海湾的鱼卵、仔稚鱼数量均处于低水平;两个海湾的产卵时期主要在春季。     

泉州湾浮性鱼卵和仔、稚鱼的种类和数量分布

根据2001-2002年在泉州湾海域分别进行4个季度月的调查资料，研究分析泉州湾鱼卵和仔、稚鱼的种类组成，数量和主要种类的分布。结果表明，本海区共出现鱼卵和仔、稚鱼34种，分别隶属于14科21属。在数量上，鱼卵和仔稚鱼最高值均出现在春季(5月)，其中鱼卵数量最大的种类是鳀科鱼类，约占总卵量34．2％。仔稚鱼则以鱚科鱼类最为丰富，占61．8％。在数量分布上，不论鱼卵或是仔、稚鱼均以9号站最为密集。这表明该区鱼类主要产卵期在春季。     

黄海硬骨鱼类鱼卵,仔稚鱼及其生态调查研究

阐述了黄海硬骨鱼类鱼卵、仔稚鱼的种类组成、数量分布及产卵场的生态特点。共鉴定68种硬骨鱼类的鱼卵、仔稚鱼，其中61种鉴定到种，隶属于7目、36科、56属。春季产卵的5种，春夏季37种，夏季7种，夏秋季4种，秋季7种，秋冬季1种，冬季1种，冬春季2种，春夏秋季3种。主要产卵场为海州湾渔场、青海渔场、石岛渔场和海洋岛渔场，形成产卵场的表层水温都在8℃以上，产卵的最适表层水温为15．0－23．0℃；盐度为31．50～33．00。并对海州湾的鱼卵、仔稚鱼种类组成的变化、高眼鲽的分布范围以及自然海域中浮性鱼卵成活状况进行了讨论。     

杭州湾北岸水域仔稚鱼的多样性和聚类分析

为了探明以杭州湾北岸水域仔稚鱼分布和多样性特征, 2019 年 5 月、8 月、11 月, 在杭州湾北岸水域设立 12 个站位点, 以大型仔稚鱼网(口径 1.3 m, 网目 0.5 mm)进行表层水平拖网采集仔稚鱼, 测量表层温度、盐度、溶氧量及 pH 值。结果表明: 共 36 次拖网调查采集到仔稚鱼 9019 尾, 其中淡水性鱼类 2 种, 河口性鱼类 12 种, 海洋性鱼类 14 种, 洄游性鱼类 11 种。斑尾刺虾虎鱼(Acanthogobius ommaturus)最多, 占总个体数的 40.32%, 其次依次为凤鲚(Coilia mystus) (15.58%)、鮻(Liza haematocheilus) (9.83%)、黄鳍多纪鲀(Takifugu xanthopterus) (1.39%)、单鳍喉褶?(Eleutherochir mirabilis) (1.36%)和有明银鱼(Salanx ariakensis) (1.35%)。仔稚鱼物种数与密度均为 5 月最多, 11 月最少。物种数和密度均呈现近岸站点较远岸站点高的现象。Shannon-Wiener 多样性指数和 Margelef 多样性指数分析表明, 两指数变化趋势较为一致, 均呈现 5 月最高, 8 月次之而 11 月最低的情况。相似性聚类分析结果显示, 杭州湾北岸仔稚鱼主要分为湾口近岸、湾口离岸和湾内 3 种群落类型, 单独对各月仔稚鱼群落进行聚类分析, 结果表明 5 月、8 月仔稚鱼主要分为湾口和湾内两种群落类型, 11 月仔稚鱼分布较为均匀, 没有明显聚类特征。     

长江口崇明东滩夏秋季仔稚鱼的空间分布

2018年6月(夏)和9月(秋),对长江口崇明东滩水域的14个站位点的表层,运用大型浮游生物网(口径1.3 m,网目0.5 mm)水平船拖10 min采集仔稚鱼,实时采集水柱环境参数包括温度(SST)、盐度(SSS)、浊度(TUR)、深度(DEP)和叶绿素a(SSC),探讨该水域仔稚鱼的分布和多样性的变化特征。结果显示,28网次共采集到仔稚鱼10 925尾。其中淡水型鱼类22种(42%),河口型(半咸水)鱼类19种(37%),沿岸型鱼类7种(13%)和近海型鱼类4种(8%)。鲤科为14种(27%);虾虎鱼科12种(23%);鳀科及银鱼科均为5种(10%)。以大于5%为优势种,凤鲚占总渔获量的21.51%、刀鲚(18.11%)、贝氏?(16.34%)、银飘鱼(10.82%)和斑尾刺虾虎鱼(9.38%)。在采集的所有仔稚鱼中,前弯曲期仔鱼数量最多,约占总数量的76.49%,弯曲期仔鱼11.94%,后弯曲期仔鱼8.01%,稚鱼3.43%,卵黄囊仔鱼仅出现在6月,占总渔获量的0.13%。前弯曲期仔鱼与弯曲期仔鱼的密度随着季节的更替呈下降趋势,后弯曲期仔鱼密度呈上升趋势。夏季仔稚鱼的物种数、个体总数及密度都比秋季多。研究表明,长江口崇明东滩鱼类可以分为两支,淡水种生态群落和半咸水生态群落。     

烟威近岸海域鱼类早期资源群落结构及适宜产卵生境

烟威近岸海域是历史上重要的鲐(Scomber japonicus)产卵场之一,或囿于对其“过路渔场”的认知,近年来对该海域鱼类产卵场的研究相对较少。为了解烟威近岸海域鱼类产卵场现状,于2020年4—9月对该海域开展逐月产卵场调查,基于鱼卵、仔稚鱼及环境数据,运用空间插值、聚类分析、非度量多维标度排序、相似性分析和冗余分析(RDA)等方法对该海域鱼类早期资源时空分布、群落结构月度更替及主要种类适宜产卵生境进行了综合分析。结果显示,2020年4—9月于烟威近岸海域采集到鱼类早期资源种类52种,包括33种鱼类的337 038粒鱼卵和28种鱼类的2122尾仔稚鱼;5—6月为主要产卵期,共有21种鱼卵出现,鱼卵数量占全年鱼卵总数的98.32%,主要产卵场位于烟台套子湾至威海鸡鸣岛北部海域,主要产卵种类为鳀(Engraulis japonicus)、鲐、蓝点马鲛(Scomberomorus niphonius)、高眼鲽(Cleisthenes herzensteini)、黄条 (Seriola lalandi)、绯 (Callionymus beniteguri)、少鳞 (Sillago japonica)、黑鲷(Acanthopagrus schlegelii)、短吻红舌鳎(Cynoglossus joyneri)、长蛇鲻(Saurida elongata)等;烟威近岸海域鱼卵与仔稚鱼群落结构年内变化明显,除产卵末期(8—9月)外,各月间种类更替率不低于50%,鱼卵与仔稚鱼群落月间平均相异性不低于73%;海表温度(SST)、海底温度(SBT)、海表盐度(SSS)和深度(DEP)是显著影响4—9月主要鱼种产卵选择的环境因子。研究表明,烟威近岸海域为黄渤海规模较大的鱼类产卵场之一,需在鱼类早期生活史研究与产卵场养护策略制定时得到足够重视。     

福建东山湾鱼卵、仔稚鱼种类组成及其丰度时空分布

本文根据2008年5月(春季)和8月(夏季)在东山湾(23°43 ′41″～23°52 ′05″N,117°28 ′27″～117°34′05″E)开展鱼卵、仔稚鱼的凋查资料,分析和讨论东山湾鱼卵和仔稚鱼的种类组成、丰度的时空分布状况.结果表明:本调查海区已分析鉴定的鱼卵仔稚鱼24种,其中16种鉴定到种,4种鉴定到属,4种鉴定到科,还有2种未能鉴定；春、夏两季东山湾鱼类生殖活动频繁,海区出现大量的鱼卵、仔稚鱼；鱼卵、仔稚鱼数量以脂眼鲱(Etrumeus teres)、金色小沙丁鱼(Sardinella aurita)、青鳞小沙丁鱼(Sardinella zunasi)、少鳞鱚(Sillago japonica)和白姑鱼(Argyrosomus argentatus)等经济鱼类为多；春季鱼卵密集区主要分布于东山湾中西部近岸水域,夏季鱼卵密集区分布在东山湾口塔屿附近水域；与福建其他海湾相比较,东山湾是洄游性经济鱼类重要的卵场所之一.     

东海生态系统中鱼卵、仔稚鱼种类组成、数量分布及其与环境因素的关系

为了解当前东海生态系统中鱼卵、仔稚鱼种类组成和数量分布的现状及其变化与物理环境因素的关系,根据2006年11月—2008年6月5个航次的鱼卵、仔稚鱼和物理环境调查资料,对鱼卵、仔稚鱼种类组成、数量分布与产卵场物理环境进行分析,探讨不同季节、不同年份鱼卵、仔稚鱼种类组成和数量分布的变化及其与物理环境的关系。结果显示,5个航次采集到74 813粒鱼卵、16 826尾仔稚鱼,共有135个种类。其中,鉴定到种的有109种,隶属于15目67科99属,还有17个种类仅能鉴定到属、6个种类仅能鉴定到科和3个种类仅能鉴定到目。2006年—2007年秋季、冬季和春季鱼卵、仔稚鱼的种类和数量随着季节变化逐渐增多;2008年春季的种类和数量较2007年春季明显偏少;2008年初夏种类的数量与2008年春季基本相近,但鱼卵的数量明显增多,仔稚鱼的数量基本相近。42种优势种类、重要种类和主要种类构成当前东海生态系统中鱼卵、仔稚鱼种类组成的主要成分。东海表层水温和盐度分布有显著的季节变化。秋、冬季表层水温锋面强度最强,春季次之,初夏最弱;锋面的位置秋季离岸最近,冬季次之,春季和初夏离岸最远,冬季偏南,初夏季节北移。表层盐度锋面主要分布在近岸区域,与岸线大致平行,其强度冬季最强,春、秋季次之,初夏季节最弱。秋、冬季节陆架深水海域的水温较沿岸海域高,鱼类生殖群体在陆架深水高温区产卵;春季和初夏季节沿岸海域明显升温,鱼类生殖群体由深水区向近岸海域进行生殖洄游,产卵场分布由陆架中部向近岸海域扩展,并在近岸海域形成了中心产卵场。鱼卵和仔稚鱼的分布与温、盐锋面和种类的温、盐属性的关系密切,主要分布在温度锋面暖水一侧,并有各自最适宜的温度和盐度范围。水温、盐度与种类的繁殖生物学特性是导致鱼卵和仔稚鱼种类组成与数量发生变化的主要因素;适宜的温度和盐度范围、锋区的辐聚和卷夹作用以及种类的生物学属性是影响鱼卵和仔稚鱼数量分布以及密集分布区形成的主要因素。     

Effects of dissolved carbon dioxide on energy metabolism and stress responses in European seabass (Dicentrarchus labrax)

Elevated carbon dioxide concentrations reduce feed intake and growth in several fish species and induce stress responses. In this study, the effects of moderately elevated CO₂ levels on performance, energy partitioning, swimming activity and stress response in European seabass were assessed. European seabass (140.0 g) were reared under two levels of CO₂ (1.6 and 7.0 mg L^?1) and two feeding levels (FLs) (maintenance and satiation) for 60 days, and fish swimming speed was recorded. At the end of the experiment, fish were subjected to an acute stress test. Blood cortisol, glucose and lactate were analysed. Energy and nitrogen balances were quantified based on measurements of body composition and digestibility coefficients. Moderately elevated chronic CO₂ level did neither affect energy requirements for maintenance nor the utilization of digestible energy for growth. However, swimming activity data suggests that FL dependent alterations in energy partitioning took place. Blood cortisol values after the acute stress were affected by additional CO₂ exposure and this effect was also dependent on FL. The elevated CO₂ exposure of 7.0 mg L^?1 appears to act as a chronic stressor as adaptive responses took place, however, this CO₂ exposure seems to be still within the allostatic load of the fish.     

Phenotypical and genotypical characterization of Shewanella putrefaciens strains isolated from diseased freshwater fish

Between 2007 and 2012, a variety of disease outbreaks most often characterized by skin disorders were observed among different species of freshwater fish in Poland. In most cases, the clinical signs included focally necrotized gills, necrotic skin lesions or ulcers. Internally, haemorrhages, oedematous kidney and abnormal spleen enlargement were generally noted. The disorders were accompanied by increased mortality. Most of the problems concerned cultured common carp Cyprinus carpio L. and rainbow trout Oncorhynchus mykiss (Walbaum). Fish have been examined from a number of these farms, and additionally, the wild and ornamental fish with similar clinical signs of diseases were also tested. Bacteria were isolated consistently from lesions and internal organs. They had characteristic orange-pigmented colonies which grew in pure culture or constituted 55–95% of total bacterial flora. One hundred and eighteen isolates were collected and biochemically identified as Shewanella putrefaciens group, and this was confirmed by sequencing. Challenge tests confirmed the pathogenicity of these bacteria. This is the first report characterizing and describing S. putrefaciens as a pathogen of different species of freshwater fish in Europe.     

中国鱼粉鱼油来源及利用

鱼粉鱼油是渔业生产的重要原料,连接着海洋捕捞业与养殖业,是现阶段渔业转型工作的一个重要部分。中国自2000年以后鱼粉鱼油使用量在每年160×104 t左右,达到一个相对稳定的水平。通过梳理近10年中国鱼粉鱼油生产原料、产量和消耗情况,分析了中国鱼粉鱼油利用现状,提出了健全渔业捕捞相关法律法规、推动鱼粉行业绿色转型、加大水产动物营养生理与饲料的科研力度等方面的建议。     

Bacteriocins and their applications for the treatment of bacterial diseases in aquaculture: a review

Aquaculture is one of the fastest growing food producing sectors in the world. The increase in the world population requires faster growth in aquaculture for better food availability and to overcome malnutrition. But this worldwide growth of aquaculture is overwhelmed by catastrophic fish diseases and spoilage during cultivation and preservation problems caused by pathogenic bacteria. Various remedies are available for food preservation and also from the bacterial diseases in the fish production. Due to the emergence of antibiotic resistance and adverse effects, an alternative to antibiotic is the need of the hour. The proteins such as bacteriocins, i.e. ribosomally synthesized antimicrobial peptides (AMPs) and possess antagonistic against closely related and other bacteria. These proteins are produced by most lineages of bacteria which are playing key roles in recognition and possess a cognate immunity system for self‐protection as well as host protection from infections. These proteins are potent immunomodulators with broad spectrum inhibition properties which are further used as novel therapeutic agents. In this review, we have tried to summarize the bacteriocins on the basis of their classifications, structural and functional attributes, mode of actions, bacteriocins isolated from fish and gut microbiota and presence of beneficiary bacteria in the fish gut. Further, this study highlighted where further research is a prerequisite to increase our basic understanding and search for novel bacteriocins to elucidate the proteins/peptides having antimicrobial properties for disease control in aquaculture as an alternative to antibiotics.     

喹乙醇在鱼饲料和鲤鱼组织中的残留量

测定了喹乙醇在鱼饲料和鲤鱼组织中的残留量。用体积分数为 2 0σ/v的甲醇提取饲料中的喹乙醇。用乙腈 -乙酸乙酯 (体积比为 3∶2 )提取鱼组织中的喹乙醇。高效液相色谱条件 :Hypersil-C18为分离柱 ( 12 5mm× 4 0mm) ;流动相为 15σ/v甲醇 ;体积流量 1 0ml·min-1;紫外检测波长 2 60nm。喹乙醇在 2～ 2 0 μg·ml 1线性关系良好 ,相关系数 0 9996。测定下限为 2 0mg·kg 1。     

Effect of fishing effort on catch rate and catchability of largemouth bass in small impoundments

Largemouth bass Micropterus salmoides (Lacepède) catch rates decline with sustained fishing effort, even without harvest. It is unclear why declines in catch rate occur, and little research has been directed at how to improve catch rate. Learning has been proposed as a reason for declining catch rate, but has never been tested on largemouth bass. If catch rate declines because fish learn to avoid lures, periods of no fishing could be a management tool for increasing catch rate. In this study, six small impoundments with established fish populations were fished for two May to October fishing seasons to evaluate the effect of fishing effort on catch rate. Closed seasons were implemented to test whether a 2‐month period of no fishing improved catch rates and to determine whether conditioning from factors other than being captured reduced catch rate. Mixed‐model analysis indicated catch rate and catchability declined throughout the fishing season. Catch rate and catchability increased after a 2‐month closure but soon declined to the lowest levels of the fishing season. These changes in catch rate and catchability support the conclusion of learned angler avoidance, but sustained catchability of fish not previously caught does not support that associative or social learning affected catchability.     

噪声对鱼类影响研究现状与展望

本文对国内外学者就噪声对鱼类听力、信息掩蔽、生理和行为等多方面的研究成果进行了总结，为噪声对鱼类的影响提供较为系统的信息资料。噪声对鱼类行为和鱼类听力、信息掩蔽、其他生理等多方面都会产生不利影响。噪声刺激会显著性增加鱼类游泳速度，减少觅食量，降低产卵成功率；导致鱼类的听力受损；阻碍鱼类之间信息交流，对鱼类寻求配偶产生不利影响，干扰鱼类回声定位；促使鱼体内生理激素、生理应激指标发生不适变化。强烈的噪声刺激会损伤鱼体的器官。目前的研究在实验声场场景、声波粒子运动、实验设置形式和试验周期监测等方面存在一定的不足，多数实验设计都无法模拟真实的声场场景；测量声音的质点运动分量方面鲜有研究；噪声暴露实验设置形式单一且很少进行周期性监测。针对当前的研究缺陷，建议从以下方面改进研究：（1）模拟真实声场场景；（2）探测声波粒子运动对鱼类的影响；（3）开展噪声暴露时间和播放形式方面的研究并进行周期性监测。     

新疆渭干河流域鱼类资源现状

2019年5月、8月和11月,在上、中、下游共设5个采样点,采用单层刺网(网目1、2、3 cm,网长20、30、40 m)和地笼网(开口40 cm×40 cm,长8 m)调查新疆天山南麓中段塔里木河流域九大水系之一的渭干河(N 41°06′~42°42′,E 80°40′~84°10′)的鱼类资源状况。调查共采集鱼类1864尾,总质量47869.05 g,隶属3目6科15属19种。土著鱼类1目4属8种,其中鲤科鱼类3属5种,鳅科鱼类1属3种。外来鱼类3目11属11种,其中鲤科鱼类6属6种,鳅科、鲈科、塘鳢科、虾虎鱼科、鲇科各1属1种。8月捕获鱼类种类最多,共17种。5月捕获渔获物数量和质量最大,占总渔获物数量的38.41%,占总渔获物质量的64.12%。渭干河优势种为斑重唇鱼、、河鲈和麦穗鱼。渭干河上游、下游河段鱼类种类稀少,群落多样性低。与历史数据相比,扁嘴裂腹鱼和重唇裂腹鱼未采集到,其他土著鱼类捕获量低,外来鱼类捕获量大。通过聚类分析,将5个采样点鱼类分为2类,经过单因子相似性分析得出,这2个群聚之间差异不显著(P>0.05)。将渭干河4种优势种和8种常见种分为2类,经过单因子相似性分析得出,这2个群聚之间差异显著(P<0.05)。外来鱼类入侵和水利工程是影响渭干河鱼类群落的主要因子。     

Effect of dietary carbohydrates and lipids on growth in cachama (Piaractus brachypomus)

The effects of diets with three contents of carbohydrates and lipids were evaluated on the growing performance of cachama Piaractus brachypomus juveniles (initial weight 7.8 ± 0.49 g). The experiments were performed a 3 × 3 factorial design (200, 280 and 360 g of carbohydrates and 40, 80 and 120 g of lipids kg^?1). Protein content was kept constant in 320 g kg^?1 and digestible energy between 11.3 and 16.1 MJ kg^?1. Simple effects and interaction of factors on growth performance varied significantly (P < 0.05) indicating dependence among them. The maximum weight gain was observed in fish fed 200 and 280 g kg^?1 carbohydrates and 40 g kg^?1 lipids. Increase of lipids from 80 to 120 g kg^?1 reduced growth significantly. Protein efficiency rate and percentages of protein retention and energy were positively correlated with carbohydrate levels and no significant differences (P > 0.05) were observed with the lipid levels. Results indicate that cachama utilizes carbohydrates as energy source more efficiently than lipids; likewise, lipid levels over 40 g kg^?1 depress growth at any carbohydrates level.