Mercury bioaccumulation in pike (Esox lucius) food chain from Anzali Lagoon, Iran

A number of wide-ranging monitoring studies have been performed in order to estimate the degree of mercury (Hg) contamination in freshwater ecosystems. Knowledge regarding contamination of different levels of the food chain is necessary for estimation of total pollutant input fluxes and subsequent partitioning among different phases in the aquatic system. The growing international concern about this environmental data is closely related to the strongly developing ecological risk assessment activities. In addition,freshwater monitoring outputs hold a key position in the estimation of the Hg dose consumed by the human population as it is highly dependent on fish consumption. So monitoring of Hg in the tissue of edible fish is extremely important because of contaminated fish has caused serious neurological damage to new born babies and adults. Mercury tends to accumulate in fish tissue, particularly, in the form of methyl mercury, which is about 10 times more toxic than inorganic mercury. The Anzali lagoon is one of the biggest wetland of Guilan province, which joins to the Caspian sea. Many Chemical and industrial factories plus agricultural runoffs and urban and rural sewages are major polluting sources of the Anzali wetland. Since many of those polluting sources drain their wastes directly or indirectly into the Anzali wetland and their sewages may be polluted with Hg, this study was conducted to find out the bioaccumulation of Hg bioaccumulation in pike (Esox lucius) food chain from Anzali lagoon, Iran. Sampling were carried out from July 2004 to July 2005, in addition 318 speciments of 9 fish species were collected. T-Hg was measured by LECO AMA 254 Advanced Mercury Analyzer (USA) according to ASTM standard No D-6722. Each sample was analyzed 3 times. Accuracy of T-Hg analysis was checked by running three samples of Standard Reference Materials; SRM 1633b, SRM 2711 & Sra 2709. Detection limit was 0.001 mg/kg in dry weight. The Accuracy degree of analyzor equipment with RSD<%0.05 (N=7) was between %95.5 and %105. In overal eigth fish species were distingushed in the gut content of 87 speciments of pike with age 1-5 year and maximum length 550mm. The max. and min. concentration of T-Hg in dorsal muscle of pjke was 0.2ppm in one year and 1.2ppm in five year class. The mean of T-Hg significantly increased with age and length increased (P<0.05).Mercury accumulation pattern in pike was as well as muscle > liver > spleen (P<0.05). THg content in female was higher than male(P<0.05). In contrast the mean of THg concentration in dorsal muscle of eigth fish species as prey was 0.282, 0.261, 0.328, 0.254, 0.256, 0.286, 0.322 and 0.241 ppm for Carassius auratus gibelio, Hemiculter leucisculus, Blicca bjoerkna transcaucasica, Chalcalburnus mossulensis, Rhodeus sericeus amarus, Gambusia holbrooki, Alburnus charusini hohenackeri & Scardinius Erythrophthalmus respectively.Liner regresion indicated that high degree of relationship between age of pike and Uptak/Intake ratio (R2=%99.12) and indicated that the mercury bioaccumulation in the pike dorsal muscle increased with age increased. BFA was >1 and and indicating the mercury biomagnification in the pike food chain. Trophy level of pike in the Anzali lagoon was estimated as well as 3.5 and 4 . It is generally agreed that Hg concentration in carnivorous fish are higher than in noncarnivorous species.

Study ectoparasite infestation of 10 common imported freshwater ornamental fish species

In the present study, ectoparasite infestation of common freshwater ornamental fish species imported into Iran including: Dwarf gourami (Colisa lalia), Angelfish (Pterophyllum scalare), Oscar (Astronatus ocellatus), Red eye Tetra ( Moenkhansia Sanctaefilomenae), Barb( Capoeta tetrazona), Arowana (Osteoglossum bicirrhosum), Goldfish(Carassius auratus), Red fin Shark (Lebeo elythrurus, Catfish (Hypostomus plecostomus) and Pangasius sutchi ( Pangasius hypophthalmus) from May until April was investigated.A total of 6 specimens sample of each fish species) randomly were obtained and taken alive to the lab. After observing gill and skin wet smear under the microscope , gill was dissected and examined carefully .Photo and films were taken from the isolated parasites and parasite identification was performed according to Yamaguti AP1), Bychowsky (■Y).From a total of examined fishes 1\ ► sample (YY.V.) were parasitized .Parasite groups that were observed consisting ciliated protozoan myxosporidian , monogenean Digenean metacercaria and crustacean .The only non-parasitized fish was Barb. Monogenea Trianchoratus sp. , Cleidodiscus sp. , Ancylodiscoides sp. , Thaparocleidus sp. , Centrocestus formosanus metacercaria and Myxobolus longisporus report for the first time in ornamental fish which imported from Southeast of Asia to Iran. According to the results, it seems that severe quarantine and sanitary rules are necessary.

新疆额尔齐斯河水系银鲫克隆多样性研究

银鲫(Carassius auratus gibelio Bloch)由于其独特的遗传背景和繁殖方式而成为研究进化遗传学和选择育种的一个独特的模式生物。到目前为止,我们对新疆额尔齐斯河水系银鲫群体的多样性状况一直知之甚少。为了更好地了解额尔齐斯河水系银鲫群体的克隆多样性状况,本研究中,我们采集了来自新疆额尔齐斯河水系的4个鲫鱼群体。通过流式细胞术分析血细胞样品,结果证实这些鲫鱼均为三倍体银鲫。通过血清转铁蛋白电泳表型分析,我们从这些银鲫群体中鉴定出总共8个不同的克隆。在这些鉴定的克隆中,有4个克隆(克隆A

天然三倍体鲫鱼突变体萍乡肉红鲫线粒体细胞色素b基因序列分析

用细胞色素b(Cyt b)基因特异性引物,对萍乡肉红鲫(Carassius auratus var.pingxiangnensis)的线粒体Cytb基因进行PCR扩增和双向测序。在12个个体中均得到序列一致的Cytb基因全序列,长度为1 140 bp。其A、T、G、C含量分别为28.2%(321)、28.8%(328)、14.8%(170)和28.2%(321),A+T含量(57%)明显高于G+C含量(43%),与其他水生动物相同基因片段碱基含量相似。该基因中密码子第1位核苷酸中4种碱基组成较为均衡;第2

甘草粗提物对鲫的抗应激及免疫保护功效研究

采用腹腔注射和混饲投喂两种方式研究中药甘草(Glycyrrhiza uralensis Fiseh)粗提物对鲫(Carassius auratus)的抗应激和免疫保护功效。将一部分粗提物按0.5%和2%的质量分数制成药饵投喂实验鲫,分别在第14 d、28 d、35 d、42 d、56 d采集血样;将另一部分粗提物用无菌生理盐水按0.5%和2%的浓度配成针剂腹腔注射鲫,分别在第3 d、7 d、14 d、21 d、28 d采集血样。结果显示:投喂实验中药物组和对照组血清皮质醇水平均呈先升后降趋势,除第14 d

甘草粗提物对鲫的免疫调节作用

本研究对中药甘草(Glycyrrhiza uralensis Fiseh)进行了粗提,将粗提物按0.5%和2%的质量分数制成药饵投喂鲫鱼(Carassius auratus)后,于第14天、28天、35天、42天5、6天采样检测其免疫指标。结果显示,低剂量组试验鱼血清溶菌酶活性逐渐升高,高剂量组在35d达到最大值(205.5±28.8)U/mL,之后略有下降。低剂量组和高剂量组试验鱼血清杀菌活性均有所波动,波动范围分别为62.0%—73.1%和75.0%—83.3%,就各期而言,对照组、低剂量组和高剂量组

金鱼Prox1基因cDNA的克隆及其在眼睛发育中的表达分析

脊椎动物的Prox1基因,与果蝇的转录因子prospero同源。为了探讨Prox1基因在金鱼眼睛发生过程中的表达图式,我们从金鱼眼睛SMART库中克隆了Prox1cDNA。它全长共2851bp,编码739个氨基酸。组织分布研究表明,Prox1主要分布于眼、脑、心、肝、脾和肾中。整体原位杂交显示,Prox1mRNA首先是在晶体期的晶体原基中有转录,心跳期则在未成熟晶体的细胞中和视网膜的幼芽区可以检测到。晶体纤维形成后,它主要定位于视纤维层和内网织细胞层。免疫组化显示,心跳期Prox1蛋白的定位与mRNA相同

银鲫ZP3的表达特征和卵壳ZP3蛋白的分离

克隆得到银鲫(Carassius auratus gibelio)ZP3基因全长cDNA,在体外表达出银鲫的ZP3融合蛋白,并制备出多抗血清;通过免疫印迹和RT-PCR分析,研究了银鲫ZP3在卵子发生过程中的表达特征和在早期发育胚胎中的状态变化。研究结果表明,银鲫ZP3的转录发生在卵黄发生以前,而ZP3蛋白的翻译起始于卵黄形成阶段,且随着卵母细胞进一步成熟,其含量不断增加。ZP3蛋白的存在状态在受精后和早期胚胎发育过程中发生了明显变化。在受精后5—30min期间,抽提液中原始的ZP3蛋白带迅速消失,取而代

长江江豚锌、铜、铅、镉和砷的摄入与累积

根据室内饲养的3头长江江豚(Neophocaena phocaenoides asiaeorientalis)食物鲫(Carassius auratus)中锌(Zn)、铜 (Cu)、铅(Pb)、镉(Cd)、砷(As)的浓度值和饲养记录,推算出了饲养条件下江豚这些微量元素每日及每周估计摄入 量的范围。必需元素的需求方面与世界卫生组织/联合国粮农组织(WHO/FAO)提出的人暂定每周耐受摄人量 (PTWI)相类似,可是毒性较强的元素Cd、As、Pb的摄入量大大高于人体的PTWI。对湖北天鹅洲故道收集到的一头

金鱼DEAD-box家族基因p68和p110在配子发生中的表达特征

利用组织原位杂交技术,以地高辛标记的反义RNA为探针,检测了金鱼(Carassius auratus)DEAD-box家族基因p68和p110在卵子发生及精子发生中的表达分布特点。结果表明:在金鱼配子发生中,p68基因在各个时期的卵母细胞均有表达,Ⅰ、Ⅱ期卵母细胞中的表达水平较Ⅲ、Ⅳ期卵母细胞中更高。p68基因的表达只限于精原细胞和初级精母细胞中。p110基因在金鱼精子发生各阶段持续表达,其中精原细胞和初级精母细胞中表达水平较高;在卵子发生中,Ⅰ期卵母细胞中没有p110 RNA阳性信号,Ⅱ期卵母细胞中信号

2,3,7,8-四氯代二苯并二英(TCDD)和苯并芘(B[a]P)对原代培养鲫鱼肝细胞中卵黄蛋白原诱导的影响

通过测定原代培养鲫鱼(Carassius auratus)肝细胞中雌激素受体所介导的卵黄蛋白原(Vtg)生成以及芳香烃受体所介导的CYP1A1基因转录水平的变化, 建立了一种类雌激素体外实验模型. 实验结果表明, Vtg和Vtg mRNA的表达与己烯雌酚(DES)之间均有很好的剂量-效应关系, Vtg和Vtg mRNA均可作为指示类雌激素毒性的生物标志物. TCDD, B[a]P可显著抑制鱼肝细胞中DES诱导的Vtg和Vtg mRNA的表达, 呈明显的抗雌激素效应, 并同时激活了CYP1A1 基因的表达;

家用洗涤剂对鱼生物标志物的影响

将鱼暴露在家用洗涤剂中1周和2周后,通过测定腺苷三磷酸(ATP)酶、谷胱甘肽硫转移 酶(GST)和脱氧核糖核酸(DNA)加合物等几种生物标志物,来评价家用洗涤剂对鲫鱼(Carassiu s auratus)的毒性影响.结果表明,暴露1周后,各指标无明显变化;暴露2周后,鳃ATP酶活性降 低,肝GST活性升高,DNA加合物相对标记水平增大;而肾ATP酶活性没有明显改变.两种家用洗 涤剂的暴露结果是一致的.研究结果表明了家用洗涤剂对鱼的毒性和潜在致癌性.

鱼类转基因早期胚胎细胞的核移植研究

像许多转基因高等生物一样,用显微注射方法研制的转基因鱼均为转植基因嵌合体,培育纯合转基因品系已成为研究者们向往和追求的目标。以澎泽鲫(Carassius auratus,Pengze var.)和黄河鲤(Cyprinus carpio,Huanghe var.)为实验材料,以转基因囊胚细胞核或原肠胚细胞核为供体,进行了细胞核移植.检测了转植基因在所获得的移核胚胎和5尾澎泽鲫移核鱼及1尾黄河鲤移核鱼中的存在状况,分析了用转基因早期胚胎细胞核移植方法研制纯合转基因鱼的可能性。

用水毒理学方法评价家用洗涤剂的潜在危害

选用5种不同产地的常用类型的家用洗涤剂,用水毒理学方法研究它们对水生动物的毒性影响并由此判断对水生态系统的潜在危害.结果表明,在远低于日常使用量的浓度下,5种家用洗涤剂均对稀有鲫(Grobiocypris rarus)鱼苗和大型(Daphnia magna,HB)有急性毒性,离体条件下对鲫鱼(Carassius auratus)鳃ATP酶有较强的抑制作用;在无急性毒性浓度下暴露时对大型繁殖有明显影响;当暴露于家用洗涤剂对鱼24h半数致死浓度的5%时鲫鱼鳃ATP酶受到明显抑制;家用洗涤剂溶液存放一段时

转入生长激素基因红鲤F_2代阳性鱼的摄食及代谢研究

<正>生长激素(GH)是由中腺垂体分泌的多功能激素,对动物生长的促进效应已无可置疑.将冠以小鼠重金属螯合蛋白(MT-1)基因启动顺序的人生长激素(hGH)基因重组质粒pMThGH显微注射到红鲫(Carassius auratus auratus)和泥鳅(Misgurnus anguillicaudatus)的受精卵内,获得了第一批转基因鱼,并进一步证实了转移基因的整合、表达、传代及转GH基因鱼的快速生长效应.由于鱼类自然群体中也存在个别的快速生长个体,对转GH基因鱼快速生