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淋巴囊肿病毒是最早发现的鱼类病毒,广泛分布于世界各地的淡水、盐水和海水中,可感染140种以上鱼类,危害巨大。本文对该病毒的形态结构特征、化学组成和理化特性、基因组及编码多肽、细胞培养特性和该病的致病机理、传播方式、诊断防治等方面进行了综述。 相似文献
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以福建近海出现过的13属23种石首鱼（Sciaenidae）作为分类单元（operationalt axonomicunits）及其量化数据取值依据，选取39个特征指标，采用系统聚类分析法（hierarchical cluster）对其进行数值分类，得出了福建近海石首鱼类的聚类分类结果．结果表明：聚类分析法的分类结果与传统的形态分类结果基本吻合，可将福建近海出现过的石首鱼类分成13类（属）．证明了朱元鼎教授等对我国石首鱼类的分类是比较科学、合理的．研究结果支持把娩状黄姑鱼（Nibea．miichthioides）归到黄鳍牙馘属（Chrysochir），这一点与传统的形态分类法观点不同．研究结果还支持了朱元鼎等的观点即认为石首鱼属（Sciaena）和叫姑鱼属（Johnius）均属较为原始型的石首鱼类．另外，本研究结果对大头白姑鱼（Argyrosomus macrocephalus）和勒氏短须石首鱼（Umbrina．russelli）的分类仍存有分歧，并提出了一些具有参考价值和值得重视的观点，有待将来进一步的探讨. 相似文献
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The threat status of 74 freshwater and estuarine fish present in New Zealand was determined. Fifty-one native taxa were ranked of which 67% were considered Threatened or At Risk. A single species was classified as Extinct, the New Zealand grayling, which has not been observed since the 1920s. Four taxa were classified in the highest threat category, Nationally Critical, and a further 10 taxa as Threatened (Nationally Endangered or Nationally Vulnerable). Twenty taxa were ranked in the At Risk group with the majority ranked as Declining. Endemic galaxiids (Galaxiidae) dominated the Threatened and At Risk taxa. The majority (68%) belonged to the Galaxias genus, comprising 81% of recognised taxa in this genus and all five species in the genus Neochanna were also ranked as Threatened or At Risk. In addition to 51 native taxa, a further three fish species were considered colonists and 20 introduced species were classified as naturalised, although two of these are considered rare. The majority of the Threatened species occur in the Canterbury and Otago regions where a suite of rare non-migratory galaxiids exist. Threat mechanisms that were identified as causal in the decline of freshwater fish species were the impact of introduced fish species, declining water quality, effects of water abstraction, loss of habitat via land-use change and land-use activities, and river modifications. 相似文献
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The live reef food fish trade (LRFFT) has caused severe depletion of the Humphead wrasse (Cheilinus undulatus) populations globally, a species considered endangered by the International Union for the Conservation of Nature. In 2010, signatories to the Convention on International Trade in Endangered Species of Wild Fauna and Flora recognized that illegal, unregulated, and unreported (IUU) activities in the LRFFT were undermining the efforts to protect this species. Management recommendations have yet to be effectively implemented at national and local levels where the fish is harvested. This paper analyzes the threats to, and socio-economic impacts of, Humphead wrasse recovery in Sabah, Malaysia, and offers both short- and longer-term recommendations for the local recovery of the species. Key issues addressed centre around understanding the threats to recovery, specifically the role of IUU and the context-specific considerations, including the socio-economic aspects of the IUU trade in Sabah. The analysis confirms that deliberate management planning and action at multiple levels are required to prevent local-scale extinction. Lessons for other species and countries involved in the LRFFT suggest that to be effective, broad management frameworks must be tailored to local situations and must focus on gaining support and participation of fish harvesters if the recovery and long-term sustainability of both the Humphead wrasse and the LRFFT are to be achieved. 相似文献
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鱼类生长激素的异源表达、应用及安全性评价 总被引：3，自引：0，他引：3
鱼类生长激素对鱼的生长发育起着重要的调节作用，能促进鱼体快速生长，提高饵料转化率，在水产养殖业中具有重大应用价值。转生长激素基因鱼具有快速生长效应，可以缩短养殖周期，降低养殖成本和风险。鱼类生长激素基因异源表达体系的建立和发展，使获得大量廉价的鱼类生长激素产品成为可能，为鱼类养殖业新型饵料添加剂的研制开辟了新的途径。本文综述了转生长激素基因鱼和鱼类生长激素基因的异源表达两方面的研究及其安全性评价。 相似文献
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《African Journal of Marine Science》2013,35(3):261-268
Prevalence of infection with the myxozoan parasite Kudoa thyrsites is not well documented in sardine Sardinops sagax, the Cape hakes Merluccius capensis and M. paradoxus, and kingklip Genypterus capensis. Quantitative polymerase chain reaction assays were used to determine the prevalence of K. thyrsites in wild-caught S. sagax (n?=?296), Merluccius spp. (n?=?162) and G. capensis (n?=?70), harvested in 2015. Sardinops sagax were harvested from the east, south and west coasts of South Africa, whereas M. capensis, M. paradoxus and G. capensis were taken from the west coast only. Relationships between K. thyrsites infection prevalence and fish capture locality, season, sex and size were determined with Chi-square tests. Prevalence was highest in S. sagax (91%), followed by M. capensis and M. paradoxus (87%) and G. capensis (40%). Prevalence was independent of sex of the host for all fish species. In the case of S. sagax only, the prevalence of infection was independent of locality of capture but depended on season, with prevalence lowest during spring and highest during autumn. No significant relationship (p?>?0.05) was found between infection prevalence and host size for any of the fish species. 相似文献
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间苯二甲酸二甲酯的好氧微生物降解及其生化途径 总被引：2，自引：0，他引：2
从红树林污泥中通过富集培养分离到4株细菌,鉴定结果是多杀巴斯德菌(Pasteurella multocida Sa)、产酸克雷伯菌(Klebsiella oxytoca Sc)、少动鞘氨醇单胞菌(Sphingomonas paucimobilis Sy)和嗜中温甲基杆菌(Methylobacterium mesophilicum Sr).在纯培养降解间苯二甲酸二甲酯(DMI)时发现,单一纯菌株不能完全矿化间苯二甲酸二甲酯,而2种或3种纯菌株组成的混合菌可以将220mg·L-1的底物在12d内完全矿化.主要的中间产物有间苯二甲酸一甲酯(MMI)和间苯二甲酸(IA).根据鉴定出的中间产物,DMI的生化降解途径为:DMI→MMI→IA→CO2 H2O.研究结果表明,DMI的2个酯基的水解是决定DMI能否完全矿化的重要步骤,但 2个酯基的酶催化水解反应有差异,由不同的细菌分步来完成,说明是酯酶对不同底物的专性所致;第2个酯基的水解对整个降解过程有决定性作用. 相似文献
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南海北部陆架区3种鱼类多氯联苯含量分布特征 总被引：1，自引：0，他引：1
为探讨南海北部陆架区海洋动物中多氯联苯(PCBs)污染状况,用气相色谱仪-电子捕获检测器测定了1998—2000年在该海域采集的3种金线鱼体内的PCBs。结果表明,在鱼体背部肌肉中PCBs含量(鲜重平均值)深水金线鱼Nemipterus bathybius中较高(6.21ng.g-1),在金线鱼N.virgatus中次之(5.26ng.g-1),在日本金线鱼N.japonicus中较低(4.83ng.g-1)。在台湾浅滩金线鱼PCBs含量(6.05ng.g-1)略高于广东海域(5.61ng.g-1),在远岸海域(5.80ng.g-1)高于近岸海域(4.48ng.g-1)。PCBs含量在深水金线鱼几种组织内的分布与脂肪含量呈正相关,表现为肝(11.9ng.g-1)>腹肌(9.05ng.g-1)>皮(4.79ng.g-1)≈背肌(4.31ng.g-1)>肠(3.53ng.g-1)≈鳃丝(3.45ng.g-1)。3种鱼体内PCBs含量(鲜重)在1.25—16.4ng.g-1范围内,远低于国内外水产品安全限量。 相似文献
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从鳕鱼碎肉中提取水解蛋白 总被引：15，自引：0，他引：15
用蛋白酶水解法从鳕鱼加工废弃物－鳕鱼碎肉中提取水解蛋白。鳕鱼碎肉经枯草杆菌ＡＳ１．３９８中性蛋白酶２４０ＩＵ／ｍｌ，ｐＨ７．０，５０℃下水解２ｈ；再经黄曲霉ＩＦＦＩ２３４２（蛋白酶活力２０００ＩＵ／ｇ）１．５％（ｗ／ｖ），５０℃，ｐＨ６．０下水解６ｈ以脱苦味。水解液经真空浓缩后喷雾干燥得水解蛋白粉。该制品易溶于水，无苦味，有海鲜味。其氨基酸组成合理，是优良的蛋白质制品。 相似文献
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VE对河蟹血清和组织中超氧化物歧化酶及磷酸酶活性的影响 总被引：12，自引：0，他引：12
通过投喂添加VE 量分别为 0、0 .1× 1 0 - 3 、0 .2× 1 0 - 3 、0 .4× 1 0 - 3 、0 .6× 1 0 - 3(m m)的 5种实验饲料饲养河蟹 6 0d ,以探讨VE 对其体内SOD、ALP和ACP等酶活性的影响 .结果表明 ,饲料中未添加VE 时 ,河蟹血清、肝胰腺、卵巢和肌肉各组织中SOD、ALP和ACP活性各异 ,其中SOD的活性从高到低依次为肝胰腺 >卵巢 >血清 >肌肉 ,ALP活性的为肝胰腺 >血清 >卵巢 >肌肉 ,而ACP活性则是肝胰腺 >血清 >肌肉 >卵巢 .饲料中添加VE 时 ,与对照组相比 ,各组织中SOD活性随着VE添加量的升高而显著降低 ( p <0 .0 5或 p <0 .0 1 ) ;ALP和ACP活性则随着VE 添加量的增加而显著升高 ( p <0 .0 5或 p <0 .0 1 ) .这表明VE 作为天然抗氧化剂在河蟹体内发挥了很大的作用 ,并促进机体的新陈代谢 ,从而增强机体的非特异性免疫力 .VE 作为免疫刺激剂能有效地增强河蟹的非特异性免疫能力 ,能有效发挥其增强河蟹免疫功能的VE 适宜添加量为 ( 0 .2～ 0 .4)× 1 0 - 3(m m) . 相似文献
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福建三沙湾浮性鱼卵和仔、稚鱼的分布 总被引：6，自引：1，他引：6
本文根据1990年2～11月在三沙湾海域分别进行4个季节调查的资料,对三沙湾鱼卵和仔、稚鱼的种类组成、丰度和主要种类的分布进行研究和探讨.结果表明,本海区共出现鱼卵和仔、稚鱼26种,分别隶属于17科22属.在数量上,鱼卵最高值出现在春季（5月）,其中鱼卵丰度较高的种类是真鲷、带鱼、鲾和康氏小公鱼等种类.仔稚鱼以夏季丰度最高,并以鰕虎鱼丰度（71.8%）最高.在分布上,鱼卵的丰度以三都岛东北部和东吾洋海域最高,仔稚鱼以三都岛东部最为密集.这表明本海区的鱼类的主要产卵季节是春季和夏季.其数量、分布与水温及桡足类的分布关系密切. 相似文献
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南海珊瑚礁周围过渡性水域主要鱼类食性与食物的关系 总被引：3，自引：0，他引：3
对路氏双髻鲨Sphyrna lewini、侧条真鲨Carcharhinus limbatus、大眼六鳃鲨Hexanchus vituius、灰六鳃鲨Hex-anchus griseus、及达尖犁头Rhynchobatus djiddensis、灰三齿鲨Triaenodon obesus、裸狐鲣Gymnosarda unicolor、扁舵鲣Auxis thazard、黄斑胡椒鲷Plectorhynchus flavomaculatus、密点胡椒鲷Plectorhynchus gaterinus、尖嘴Dasyatis zugei、星点Caranx stellatus、黑Caranx lugubrisr等13种南海主要珊瑚礁周围过渡性水域鱼类进行食性分析,根据其胃含物中饵料生物的重量组成和出现频率,分为4种食性类型。同时还分析了13种鱼的食物关系和营养级,为该海域渔场生态系食物网的研究提供基础资料。 相似文献
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闽南-台湾浅滩海域鱼类资源生产量 总被引：8，自引：0，他引：8
以海洋生态系统营养动力学为理论依据,根据调查所获得的有关闽南-台湾浅滩海域的初级生产力资料,检测了该海域的浮游植物有机碳含量,测算了生态效率,检测了52种主要经济鱼类营养级及其有机碳含量.采用营养动态模型和Cushing模型估算了该海域生态系统中鱼类资源的生产量(自然生产量),同时采用Cadima模式和MSY简单模式估算鱼类资源最大可持续开发量.估算结果如下鱼类资源生产量为98.63×104t,最大可持续开发量为 48.35×104t.1997年以来实际年渔获量为48.64×104t -53.83×104t,超过了鱼类资源的最大可持续开发量,呈现过度捕捞态势.还讨论了加强该渔场渔业资源管理的7项重要措施,以促进鱼类资源的较快恢复. 相似文献
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云斑尖塘鳢人工育苗技术初步研究 总被引：1，自引：0，他引：1
对云斑尖塘鳢（Oxyeleotris marmoratus （Bleeker））人工育苗技术进行了初步的研究,利用燃油热水炉加温进行亲鱼越冬,采取人工辅助控温、保温的方法,配合其生态条件的调控和投喂优质饲料,培育亲鱼成熟并能自然产卵,使用人工饵料、代用饵料、生物饵料等混合饵料互相搭配组合,经过2个月左右的培育鱼苗全长达3cm左右。亲鱼具多次产卵习性,观察到一年当中最多产卵4次。利用外源激素催产率达到95．0％,自然产卵的受精率和孵化率均高于人工催产。 相似文献