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1.
鲈鱼生长催乳素的分离纯化与N-末端序列分析   总被引:1,自引:1,他引:0  
生长催乳素(SL)是生长激素/催乳素家族的一种新的脑垂体蛋白质激素,本研究首次从鲈鱼脑垂体中分离得到.鲈鱼脑垂体在碱性条件下,经葡聚糖凝胶(SephadexG-100)过滤和反相高效液相色谱(rpHPLC)分离出纯化的鲈鱼生长催乳素,(sbSL),并与大麻哈鱼生长催乳素(sSL)抗体发生特异性的Western免疫印迹交叉反应证实.SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)分析,发现鲈鱼生长催乳素分别是由分子量为23.2×103和28.4×103u两种形式组成(后者可能是一种糖基化形式).根据Edman降解原理,测得鲈鱼生长催乳素的N-末端16个氨基酸的序列,它与已知鱼类生长催乳素的N-末端序列比较,具有较高的同源性;由此进一步证实,分离纯化得到的鲈鱼生长催乳素是正确的.  相似文献   

2.
花鲈和鲈鱼群体的遗传分化研究   总被引:1,自引:0,他引:1  
利用随机扩增多态DNA(RAPD)技术对3个中国花鲈(Lateolabrax maculatus)群体(威海,舟山和北海)和4个日本鲈鱼(L.japonicus)群体(东京湾、山口、有明海和八代海)进行了遗传分化研究。18条随机引物在7个群体中共扩增出159条谱带,其中多态性谱带133条(83.65%)。花鲈和鲈鱼群体间的平均等位基因数和平均有效等位基因数分别为1.836 5和1.524 2,Nei’s多样性指数和Shannon多样性信息指数分别为0.3075和0.4586。花鲈和鲈鱼群体内的遗传多样性分别为0.3156~0.3669和0.2982~0.5150。UPGMA聚类分析显示,舟山、威海和北海3个花鲈群体亲缘关系较近并形成一分支,而日本有明海与八代海的鲈鱼群体同花鲈关系较远,它们与另2个鲈鱼群体(东京湾和山口)形成另一分支。本文结果进一步从分子水平上支持将中国产花鲈和日本的鲈鱼划分为2个种的观点,并且RAPD数据表明花鲈和鲈鱼群体内都出现了明显的遗传分化。  相似文献   

3.
The sea surface is an important habitat for the developmental stages (eggs and larvae) of many fish and invertebrates; it is also a concentration point for anthropogenic contaminants entering the sea. Studies were conducted to determine the extent to which the sea surface of Puget Sound was toxic to the early life history stages of fish. Three urban bays with suspected contamination, a rural reference bay, and a Central Sound site were compared. Surface-dwelling eggs and organisms (zooneuston) were collected with a surface-skimming neuston net and their densities enumerated. Sand sole (Psettichthys melanostictus) embryos were exposed in the field and laboratory to the sea-surface microlayer. To develop a useful year-round approach to monitoring sea-surface toxicity, larval development of anchovies, kelp bass, and sea urchins was also evaluated as an indication of sea-surface microlayer toxicity.During the spawning season (February and March), urban boys in Puget Sound had lower concentrations of sand sole eggs and neustonic organisms on the sea surface than did the rural bayor Central Sound reference sites. Compared to the reference sites, laboratory exposure to surface microlayer samples collected from urban bay sites generally resulted in more chromsomal aberrations in developing sole embryos, reduced hatching success of sole larvae, and reduced growth in trout cell cultures. In situ hatching success of sole eggs was reduced by half or more in urban bays compared to reference sites.Toxicity was associated with visible surface slicks and, in urban bays, increased with increasing surface pressure (dynes cm−1). Results to be reported separately (Part II) indicate that toxicity is strongly correlated with the presence of high concentrations of polycyclic aromatic hydrocarbons and metals in the sea-surface microlayer. The toxicity of SMIC samples was similar when evaluated by sole, anchovy, kelp bass, or sea urchin tests. A sea-surface monitoring program could use sea urchin embryos to evaluate site-specific sea-surface toxicity throughout the year.  相似文献   

4.
A vital component of marine policy is the conservation and management of diverse marine resources. In the southeastern US, commercial fishermen target black sea bass (Centropristis striata) with pots from North Carolina to Cape Canaveral, Florida. During the fall through spring fishing season, western North Atlantic right whale (Eubalaena glacialis) distribution overlaps the black sea bass commercial pot fishery. Fishermen interviews revealed that the number of pots set ranged from 3 to 240 and the number of pots set per trawl ranged from 1 to 18. Generally, the amount of gear increased from south to north.  相似文献   

5.
Spores of a new species of Nematopsis have been found in the green‐lipped mussel Perna canaliculus Gmelin. This is the first record of a sporozoan parasite of a New Zealand shellfish.  相似文献   

6.
Abstract

New Zealand sea lions, Phocarctos hookeri (Gray, 1844), on Main Island of the Snares Islands (48° S) are restricted to the eastern coastal region between Molly Bay and Punui Bay. In the 1970–71 summer, a maximum of 47 sea lions (36 ?, 11 ?) was counted in one day, 5 January 1971.

A female and pup were seen several times in January and February 1969, and a second mother‐pup pair in January 1971. These sightings, with a similar record in 1907, show that small numbers of sea lions may breed on the Snares Islands, north of the main breeding area at the Auckland Islands (51° S).  相似文献   

7.
LED光色对欧洲舌齿鲈幼鱼抗氧化能力和消化能力的影响   总被引:1,自引:0,他引:1  
作者利用循环水养殖实验系统,研究了红、绿、白、黄、蓝5种光色对欧洲舌齿鲈(Dicentrarchus labrax)幼鱼抗氧化能力和消化能力的影响。结果表明,红光组的欧洲舌齿鲈幼鱼超氧化物歧化酶(SOD)活力显著高于其他光色组(P0.05),而绿、白、黄和蓝光色组的SOD活力没有显著性差异;红光组的还原型谷胱甘肽(GSH)含量显著高于其他光色组(P0.05),绿、白光组与黄、蓝光组的GSH含量之间有显著性差异(P0.05);红光组过氧化氢酶(CAT)活力显著高于其他光色组(P0.05),白光组的CAT活力显著低于其他光色组(P0.05)。黄光组的胃蛋白酶活力显著高于红、绿、白光组(P0.05),绿光组的胃蛋白酶活力显著低于其他光色组(P0.05);红、绿、蓝光组的淀粉酶活力要显著高于白、黄光组(P0.05),红、绿、蓝光组的淀粉酶活力没有显著性差异,黄、白光组的淀粉酶活力没有显著性差异;白光组纤维素酶活力显著高于其他光色组(P0.05),绿光组的纤维素酶活力显著高于红、蓝光组(P0.05),黄光组的纤维素酶活力和绿、红、蓝光组没有显著性差异。因此,欧洲舌齿鲈在红光下养殖,其体内的抗氧化能力强,能有效应对氧化应激,而在黄光或红光下养殖其消化能力更强。  相似文献   

8.
Concentrations of ten polybrominated diphenyl ethers (PBDEs) and eight methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in mullet (Mugil cephalus) and sea bass (Dicentrarchus labrax) collected from the Bizerte Lagoon and the Mediterranean Sea were investigated. To the best of our knowledge, this is the first report of these compounds in marine fishes from Tunisia. The PBDE mean concentrations in fish from Bizerte Lagoon were 45.3 and 96.2 ng g(-1) lw respectively in mullet and sea bass, while the concentrations of these compounds in mullet and sea bass from Mediterranean Sea were 7.80 and 27.9 ng g(-1) lw respectively. MeO-PBDE concentrations in mullet and sea bass from Bizerte Lagoon ranged from 6.46 to 286 ng g(-1) lw and from 49.4 to 798 ng g(-1) lw respectively, while the concentrations of these compounds in mullet and sea bass from Mediterranean Sea ranged from 190 to 401 ng g(-1) lw and from 353 to 578 ng g(-1) lw respectively. The total PBDEs and total MeO-PBDEs concentration in fish from Bizerte Lagoon were similar or slightly lower than those reported for other species from other locations around the world.  相似文献   

9.
Two silver (migratory) male freshwater eels, Anguilla dieffenbachii, were caught in a commercial trawl net in the South Taranaki Bight in April 2014. The capture date and the relatively small eye size indicated that both eels had probably only recently entered the sea. This is the first record of male A. dieffenbachii caught at sea, en route to the presumed spawning area in the South Fiji Basin.  相似文献   

10.
The health benefits of regular consumption of fish and seafood have been espoused for many years. However, fish are also a potential source of environmental contaminants that have well known adverse effects on human health. We investigated the consumption risks for largemouth bass (Micropterus salmoides; n = 104) and striped mullet (Mugil cephalus; n = 170), two commonly harvested and consumed fish species inhabiting fresh and estuarine waters in northwest Florida. Skinless fillets were analyzed for total mercury, inorganic arsenic, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F), polychlorinated biphenyls (PCBs), and organochlorine pesticides. Contaminant levels were compared to screening values (SV) calculated using U.S. Environmental Protection Agency (EPA) recommendations for establishing consumption advisories. Largemouth bass were found to contain high levels of total mercury at all sampling locations (0.37–0.89 ug/g) and one location exhibited elevated total PCBs (39.4 ng/g). All of the samples exceeded Florida fish consumption advisory trigger levels for total mercury and one location exceeded the U.S. EPA SV for total PCBs. As a result of the high mercury levels, the non-cancer health risks (hazard index–HI) for bass were above 1 for all locations. Striped mullet from several locations with known point sources contained elevated levels of PCBs (overall range 3.4–59.3 ng/g). However, total mercury levels in mullet were low. Eight of the 16 mullet sampling locations exceeded the U.S. EPA SV for total PCBs and two locations exceeded an HI of 1 due to elevated PCBs. Despite the elevated levels of total PCBs in some samples, only two locations exceeded the acceptable cancer risk range and therefore cancer health risks from consumption of bass and mullet were determined to be low at most sampling locations.  相似文献   

11.
The parasite assemblage of snoek Thyrsites atun, a commercially important fish in the Benguela system, was examined over a one-year period. In all, 16 parasite taxa including eight new host records (Bolbosoma vasculosum, Caligus coryphaenae, Caligus dakari, Corynosoma australe, Hatschekia conifera, Nothobomolochus fradei, Rhadinorhynchus cadenati, Tentacularia coryphaenae) and four new locality records (B. vasculosum, C. dakari, Molicola uncinatus, Pseudoterranova sp.) were recovered from 210 specimens. The dominance of larval helminths in the component community suggests that T. atun occupies an intermediate position in the food web. The ‘nestedness metric based on overlap and decreasing fill’ (NODF) indicated that the parasite assemblage exhibited no nestedness (NODF = 73.3, p = 0.103). Generalised additive mixed modelling results indicated that host length is the main determinant of parasite species richness in T. atun. PERMANOVA and ANOSIM suggested that infracommunity structure varied little with respect to the sex, length, seasonality and capture region of the host. The stability and randomness in parasite acquisition, as indicated by the lack of nestedness of the parasite assemblage, can be ascribed to the opportunistic feeding behaviour and nomadic movement of T. atun in the southern Benguela. The homogeneity of the community structure of long-lived endoparasites suggests that a single T. atun stock occurs off South Africa.  相似文献   

12.
The invasion of Mont-Saint-Michel Bay salt marshes (France) by a grass species (Elymus athericus) has led to important changes in vegetation cover, which is likely to modify the habitat for many invertebrates. Some of them constitute the main food items for several fish species, such as young sea bass (Dicentrarchus labrax) and sand goby (Pomatoschistus minutus), that feed in salt marsh creeks during high tides. As a result, fish nursery functions of salt marshes could be modified by the E. athericus invasion. In order to test this hypothesis, gut contents of the two most abundant fish species (sea bass and sand goby) were compared before and after E. athericus invasion in the same salt marsh creek and using the same methodology. The accessibility and availability of the main food item, the semi-terrestrial amphipod Orchestia gammarella, were estimated and compared between invaded (dominated by E. athericus) and original areas (dominated by Atriplex portulacoides). Gut content analysis showed a significantly greater percentage of fish leaving with empty guts from E. athericus areas than from A. portulacoides areas. The sea bass diet composition study showed a major shift in the relative importance of the main food items: before E. athericus invasion, diets were dominated by the semi-terrestrial species O. gammarella, whereas after the E. athericus invasion they were dominated by a marine mysid Neomysis integer. The same trend was found for sand gobies, with a shift of the main food item from O. gammarella before invasion to the polychaete Hediste diversicolor after invasion. These trophic changes may be explained by the lower accessibility and availability of O. gammarella in invaded communities than in natural ones. The E. athericus invasion, observed throughout northern Europe, is thus likely to disturb trophic function of natural salt marshes for fish. This preliminary study of the E. athericus invasion is also an illustration that invasive species are an urgent problem in conservation biology.  相似文献   

13.
During a research cruise carried out in April 2010, aimed at updating the knowledge on the biodiversity of the Santa Maria di Leuca (SML) cold‐water coral province (Mediterranean Sea), a facies of the sea pen Kophobelemnon stelliferum (Muller, 1776) was found on mud‐dominated bottoms. This finding represents a new species and a new habitat record from the SML coral province as well as a new bathyal facies in the whole Central Mediterranean Sea. The colonies were collected using an epi‐benthic sledge, at depths between 400 and 470 m. A significant positive relationship between polyp number and colony length was detected. Density of the colonies ranged from 0.003 to 0.038 N·m?2. Differences and affinities between Mediterranean and Atlantic occurrences of K. stelliferum are discussed.  相似文献   

14.
本文根据现有文献资料和笔者的研究结果,比较了不同产地,不同种群鲈鱼的形态、生态特征和各地的养殖结果,分析了产生不同结果的重要原因,提出了充分利用不同种类及产地的鲈鱼为人类造福。  相似文献   

15.
European intertidal salt marshes are important nursery sites for juvenile fish and crustaceans. Due to the increasing threat of habitat loss, the seasonal changes of salt marsh fish communities need to be understood in order to appreciate the ecological and economic importance of the saltmarsh habitat. This study was the first in Great Britain to investigate the seasonal changes of salt marsh fish communities and the variation in community structure between closely located marsh habitats. Between February 2007 and March 2008, five marshes on three estuaries of the Essex coastline were sampled using flume nets to block off intertidal creeks at high tide. Fourteen fish species were caught. The community overall was dominated by three species that made up 91.6% of the total catch: the common goby Pomatoschistus microps (46.2% of the total catch), juvenile herring Clupea harengus (24.3%), and juvenile and larval sea bass Dicentrarchus labrax (21.2%). Cluster analysis demonstrated clear seasonal patterns, with some community structures unique to specific marshes or estuaries. The marsh fish community shifts from a highly diverse community during spring, to a community dominated by D. labrax and P. microps in autumn, and low diversity during winter months. Gravimetric stomach content analysis of fish community identified three main trophic guilds; macroinvertivores, planktivores and omnivores. The macroinvertivore feeding guild contained D. labrax and P. microps, the two most frequently occurring species. This investigation demonstrates the importance of British salt marshes as nursery habitats for commercial fish species.  相似文献   

16.
The parasite faunas of tarakihi Cheilodactylus macropterus (Bloch & Schneider) from East Cape, Tasman Bay, and the Chatham Islands were compared. A total of seven parasite species were found of which four were recorded in tarakihi for the first time: Nybelinea sp., Hepatoxylon trichiuri (Holten), Echinorhynchus sp. and Clavellodes sp. The last two of these were new records for New Zealand. The other parasites were: Contracaecum sp., Anisakis sp. and Aethon garricki Hewitt. The nematode Anisakis sp. and the copepods Aethon garricki Hewitt and Clavellodes sp. were the commonest parasites.

Incidence and intensity of Anisakis sp. were high off the Chatham Islands, moderate off East Cape, and low in Tasman Bay. These differences in infestation were truly regional and were only partially caused by differences in age composition of the fish samples. Intensity of infestation with Anisakis sp. was related to age of fish off the Chatham Islands, but not in the other two areas, and this probably reflects regional differences in the diet of the tarakihi.

Incidence of Clavellodes sp. was low in Tasman Bay. This parasite was absent from the other two areas, which either may indicate a true regional difference in the distribution of the parasite or may be caused by differences in the age composition of the samples.

Incidence of Aethon garricki was moderate in Tasman Bay and off East Cape, but this parasite did not occur in the Chatham Islands tarakihi. Thus, tarakihi populations from three widely separated areas differed from each other in the incidence and intensity of at least one of the three commonest parasites.  相似文献   

17.
田丹  姜国良  刘云 《海洋科学》2013,37(10):47-52
通过研究不同体质量仿刺参(Apostichopus japonicus)的免疫活性, 为仿刺参生长中免疫指标的建立提供依据。实验选取了50、100、150 g 左右的仿刺参各10 只, 测定其体腔细胞数量、各细胞类群比例及部分免疫酶活性。结果表明: 不同体质量的仿刺参, 其体腔细胞数量及各细胞类群、过氧化物酶(POD)、超氧化物歧化酶(SOD)具有显著性变化, 而体腔液中酚氧化酶(PO)活性极低。体质量150 g左右仿刺参的细胞数量和SOD活性较其他两组都明显升高, 细胞类群也有明显变化(P<0.017), 但POD活性显著降低(P<0.05)。不同体质量的仿刺参免疫活性具有显著性差别, 说明了仿刺参免疫组分在生长过程中不断变化, 免疫防御能力在各阶段有所差别。  相似文献   

18.
Estuaries are regarded as valuable nursery habitats for many commercially important marine fishes, potentially providing a thermal resource, refuge from predators and a source of abundant prey. To assess the extent of estuarine use by juvenile (0+) common sole (Solea solea), whiting (Merlangius merlangus) and European seabass (Dicentrarchus labrax) we: (1) developed techniques to distinguish between estuarine and coastally-caught juveniles using otolith chemistry; and (2) examined the accuracy with which multi-elemental signatures could re-classify juveniles to their region of collection.High-resolution solution-based inductively coupled plasma mass spectrometry (HB-SB-ICPMS) was used to quantify 32 elements within the juvenile otoliths; 14 elements occurred above detection limits for all samples. Some elemental distributions demonstrated clear differences between estuarine and coastally-caught fish. Multivariate analysis of the otolith chemistry data resulted in 95–100% re-classification accuracy to the region of collection. Estuarine and coastal signatures were most clearly defined for sole which, compared to bass and whiting, have low mobility and are less likely to move from estuarine to coastal habitats between larval settlement and later migration to adult stocks. Sole were the only species to reveal an energetic benefit associated with an estuarine juvenile phase. The physiological ability of bass to access upper estuarine regions was consistent with some elemental data, while the high mobility and restricted range of whiting resulted in less distinct otolith chemistries.  相似文献   

19.
魏靖乘  孔令锋 《海洋与湖沼》2023,54(4):1134-1148
由于部分囊舌目物种存在较大程度的种内变异,我国早期基于形态学的囊舌目研究存在种名鉴定错误、同物异名等现象。为解决我国沿海囊舌目物种种名使用混乱的问题,结合比较形态学和分子系统学技术手段,对采自山东青岛、浙江舟山、海南陵水的囊舌目样品进行了外部形态和齿舌扫描电镜的检视,并基于COI基因进行系统发育树和遗传距离分析,对国内记录的深绿海天牛Elysia atroviridis Baba,1955重新进行了分类学描述;发现华丽海天牛Elysia ornata (Swainson,1840)应暂定为三边海天牛Elysia marginata (Pease,1871);指状棍螺Placida dendritica (Alder&Hancock1843)是马场棍螺Placida babai Ev. Marcus,1982的误定。回顾了以上几种囊舌目物种及其相似物种的分类学研究历程,对E. atroviridis、E. marginata和P. babai进行了分子系统学和形态学研究,并为解决这三种囊舌目物种的分类存疑问题提供了新的材料和方法。  相似文献   

20.
The angelfish Brama brama is a mesopelagic species distributed circumglobally in temperate to warm-temperate waters, including continental-shelf-edge and upper-slope waters of the Benguela Current ecosystem. Little is known about the parasite assemblage of Benguela B. brama, with only three parasite taxa having previously been documented from this species in the southern Benguela. This study describes the macroparasites recorded from 35 B. brama collected during research surveys off the west coast of South Africa in 2015 and 2016. A total of six macroparasite taxa were documented, including the nematode Anisakis pegreffii, the copepod Hatschekia conifera, the cestode Hepatoxylon trichiuri, an acanthocephalan from the genus Rhadinorhynchus, a monogenean from the family Diclidophoridae, and an unidentified species. Three of these (He. trichiuri, Rhadinorhynchus sp. and the unidentified species) had not previously been found to infect B. brama. The most prevalent macroparasite taxa were A. pegreffii (94%), the unidentified species (71%) and Ha. conifera (60%). Two of the parasites, Ha. conifera and He. trichiuri, showed seasonal variation in infection, and infection with the latter was positively correlated with host length. These findings increase our knowledge of B. brama biology and contribute to our understanding of the biodiversity of the southern Benguela ecosystem.  相似文献   

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