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依据2014年8月对山东省近岸贝类养殖区的调查资料,研究了养殖区海水、沉积物和生物体中6种重金属的含量及富集情况,并对贝类养殖区进行质量及生态风险评价.结果显示,海水中重金属含量从高到低为As、Cu、Cr、Pb、Cd和Hg;沉积物中重金属含量从高到低为Cr、Pb、Cu、As、Cd和Hg;贝类体中重金属含量从高到低为Cu、As、Cd、Cr、Pb和Hg.生态环境质量评价结果表明,养殖区海水中重金属含量均符合Ⅱ类海水水质标准;沉积物重金属含量均符合Ⅰ类海洋沉积物质量标准;贝类体中Hg、Cd、Pb和Cr均符合《食品安全国家标准食品中污染物限量》,Cu符合Ⅰ类海洋生物质量标准.贝类对重金属的富集能力从大到小为Cu、Cd、Hg、Pb、Cr和As,调查海域贝类体中的Cu、Cd富集系数较高,其他重金属富集系数相对较低.重金属质量安全风险分析表明,贝类体中Cd、Pb、As、Cr和Hg的膳食暴露量较低,处于安全范围内,但建议去除内脏后食用. 相似文献
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据2014年5月和8月福建安海湾9个站位的调查资料,分析海水、水中悬浮物和表层沉积物中Cu、Pb、Zn、Cd、Hg等5种重金属和类金属As的含量及分布特征,用单因子指数法、潜在生态危害评价法评价湾内重金属污染程度。结果表明,海水分布从湾顶往湾内和湾口逐渐降低,以湾顶值最高;水中悬浮物Cu、Pb、Zn、As、Hg含量以AH5站最高,Cd含量以AH6站最高,并向周边逐渐降低;表层沉积物含量从AH5站向湾内及湾口逐渐降低。部分站位海水和沉积物中Cu、Zn含量相对偏高,Pb、Cd、As、Hg含量均符合海水及沉积物质量标准的第一类要求。安海湾海域不同介质中悬浮物的含量最高,表层沉积物次之,海水的含量最低。水中悬浮物8月含量潜在生态危害程度远大于5月,以AH5站的潜在生态危害程度最强,主要潜在生态危害元素为Cd和Hg;表层沉积物以AH1、AH5站的潜在生态危害程度稍强,主要潜在生态危害元素为Cd,Hg次之。安海湾海域环境受到不同程度的重金属污染,陆源重金属污染物排放成为主要来源,本研究为安海湾海域生态环境防治提供科学依据。 相似文献
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根据2012年3月、5月、8月、11月表层沉积物调查资料,分析了双岛湾附近人工鱼礁区表层沉积物重金属的分布特征,采用潜在生态风险评价法对重金属的生态危害进行了评价。结果表明:(1)研究海域表层沉积物中重金属含量较低,全部测站Cu、Zn、Pb、Cd、Hg、As的含量符合《海洋沉积物质量》(GB 18668-2002)Ⅰ类标准;(2)表层沉积物中重金属的分布较为规律,除Hg含量站间差异不明显外,鱼礁区内站点的Cu、Zn、Pb、Cd、As重金属含量低于周边海域;(3)表层沉积物中重金属含量的月际变化比较明显,以8月最高、3月最低;(4)双岛湾附近海域重金属污染程度为低级,且总体潜在生态危害属轻微水平。 相似文献
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研究调查了青岛近海潮间带生物体重金属含量并采用单因子污染指数法进行了污染评价。研究表明,青岛近海潮间带调查生物中重金属含量差异较大,不同生物对重金属元素富集具有偏好性,长牡蛎中Cu及Zn的含量最高,锈凹螺中Pb、As、Hg及Cr含量最高,史氏背尖贝中Cd的含量最高;单因子污染指数发现青岛近海潮间带生物体中Cu、Pb、Zn、Cd及Cr处于正常背景水平,而Hg及As在个别站位采集的生物出现轻污染、污染或者重污染情况,尤其是As;同其他海区同物种或者近缘物种比较发现,砷的含量要高于其他海区,其他重金属含量偏低或者相近。 相似文献
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乳山湾贝类体中重金属含量及其评价研究 总被引：14，自引：2，他引：14
研究了乳山湾6～9月间贝类体内Cu、Zn、Pb、Cd、Cr、As、Hg等重金属含量富集水平，结果表明，贝类体内以Cu、Zn含量最高，特别是牡蛎体内Cu含量在8月中旬高达69．09mg／kg·ww，较其他重金属含量高得多，反应了该湾受Cu污染较严重，但均未超过海洋生物体内有关软体双壳类的污染评价标准。 相似文献
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本文分析了2005—2015年其中4年东碇临时海洋倾倒区及邻近海域表层沉积物中Cu、Pb、Zn、Cd、Hg、As共6种重金属含量及时空分布特征,并采用潜在生态风险指数对重金属污染现状及潜在生态风险进行评价。结果表明:历次调查重金属含量均较低,符合国家海洋沉积物质量一类标准;Cd、Cu的空间分布不均匀,其余4种重金属指标空间分布差异不大,在表层沉积物中,As、Pb、Zn富集程度相对较高,而Cu、Hg、Cd较低;东碇临时海洋倾倒区及邻近海域沉积物重金属综合潜在生态风险处于较低水平,风险排序为AsPbHgCdCuZn,其中As、Pb和Hg为主要潜在生态风险因子。 相似文献
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赤水河主要经济鱼类重金属含量及风险评价 总被引：2，自引：0，他引：2
为了解赤水河鱼体重金属富集现状及其潜在的生态风险和食品安全,测定了赤水河茅台江段和赤水江段的黄颡鱼(Pelteobagrus fulvidraco)、蛇鮈(Saurogobio dabryi)和大口鲇(Silurus meriordinalis)肌肉和肝脏中的重金属含量。分别使用电感耦合等离子体原子发射光谱法测定Cu、Zn、Pb、Cd、Fe、Cr和Mn的含量,原子荧光光度法测定As和Hg的含量。结果表明:大口鲇肌肉中Cu、Zn、Pb、Cd、Fe、Cr和Hg的含量高于黄颡鱼和蛇鮈,3种鱼类肝脏中的重金属含量均高于肌肉。所有鱼体肌肉中的重金属含量均低于国家标准,但大口鲇肌肉中Pb和Cd的含量高于欧盟委员会标准。危害指数分析表明:赤水河野生鱼类食用的人体健康风险较小。重金属单因子污染指数的结果表明赤水河鱼体Pb和Cd的污染程度较高,赤水河存在潜在的重金属污染风险。 相似文献
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根据2003年对乳山湾东湾表层沉积物中重金属调查结果，对重金属含量分布及富集特征进行分析，并采用瑞典科学家Hakanson提出的潜在生态危害指数法对其生态危害程度进行评价。结果表明，乳山湾沉积物中的重金属含量，除5月的Hg、As平均含量略低于8月外，其他重金属(Cu、Zn、Pb、Cd)平均含量5月高于8月。在表层沉积物中Cd的富集程度最大，除5月1号测站外，污染指数超过1．0。水平分布除Cd为湾口处含量较低外，其他重金属基本呈湾口和湾底含量较高的分布趋势。单个重金属潜在危害系数表明，Cd的E值大于其他重金属的E；值，其他重金属的E值均小于Hakanson所提出的沉积物重金属生态危害程度的轻微危害程度的划分标准，表明重金属对乳山湾生态环境具有潜在影响的元素主要是Cd，污染程度由高到低依次为Cd、Hg、As、Pb、Cu、Zn。与历史同期调查相比，表层沉积物中Cd含量升高幅度最大。从多个重金属的潜在生态危害指数看，两次RI调查均值小于150，属于轻微的生态危害。 相似文献
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为查明辽东湾北部近岸海域表层沉积物中重金属Cd、Hg、As、Cu、Pb和Zn的含量特征、生态效应与潜在生态风险,2017年8月对辽东湾北部近岸海域进行了1个航次的现场调查。调查结果显示,重金属Cu、Pb、Zn、Cd、Hg和As含量平均值分别为25.80、21.83、80.91、0.28、0.06和12.72mg/kg。生态效应评价显示,有7个站位的As含量位于效应浓度低值(ERL)与效应浓度中值(ERM)之间,只是偶尔会产生不利的生态效应,所有站位的Cu、Pb、Zn、Cd和Hg含量均低于ERL,几乎不会产生不利的生态效应。潜在生态风险分析结果显示,辽东湾北部近岸海域表层沉积物中,Cd、Hg和As的潜在生态风险系数较高,Cu、Pb和Zn的潜在生态风险系数相对较低,辽东湾北部近岸距离河口较近的海域是潜在生态风险较大区域。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
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In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
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Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
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Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
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Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
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Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
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