不同浓度的五氯酚对斑马鱼运动行为的影响

由于突发性水源污染频发,建立一种实时的风险监测评估系统十分迫切。本研究通过在线生物监测仪实时记录斑马鱼在五氯酚(PCP)中暴露前后的3D行为响应数据,分别从运动轨迹、游动速度(中值)、浮出水面频率及熵值4个指标分析斑马鱼的行为响应。结果表明：与对照组相比,暴露于低浓度(0.25、0.5 mg·L^-1)的PCP中的斑马鱼,其游动速度(中值)和熵值呈递减趋势,但趋势不明显,其浮出水面频率有不同程度的增加;而暴露于较高浓度(1.0、2.0 mg·L^-1)的PCP中的斑马鱼,其游动速度(中值)、浮出水面频率、熵值约有10 min的急速升高之后降低;暴露于高浓度(4.0 mg·L^-1)的PCP中的斑马鱼,所有指标均呈明显下降趋势。这表明斑马鱼的毒性行为响应随PCP的浓度变化而变化,所以可以通过监测鱼类的行为变化来反映水体的污染状况。因此,鱼类行为学研究在高浓度突发性水源污染的实时监测方面具有一定的应用前景。     

马拉硫磷和百菌清胁迫下斑马鱼行为变化的研究

以马拉硫磷和百菌清为胁迫因子,本文研究了2种污染物暴露下斑马鱼行为强度的变化。首先通过急性毒性试验确定了2种农药对斑马鱼24 h、48 h、72 h、96 h的半致死浓度(LC50),其次以LC50-48 h为1个染毒单位(TU),在0.01 TU、0.1 TU、0.5 TU、1 TU、2 TU 5个条件下,本文开展了斑马鱼行为学研究。结果显示,48 h马拉硫磷暴露斑马鱼的LC50为5 mg·L~(-1),百菌清暴露斑马鱼的LC50为0.01 mg·L~(-1)。随着污染物浓度增大,综合行为强度变化幅度增大。在设置的暴露浓度下,斑马鱼的行为强度在急剧增大或减小后都出现了明显的调节适应过程,基本符合环境压力模型。通过比较在不同频率下的影响强度,马拉硫磷和百菌清暴露斑马鱼摆鳍所受影响最大。本研究提示,水质监测中可增加斑马鱼摆鳍观察指标。     

马拉硫磷急性暴露对斑马鱼的行为毒性研究

以斑马鱼为受试生物,通过水质毒性生物监测仪记录行为轨迹,研究了亚致死浓度的马拉硫磷急性暴露下斑马鱼游动行为和群体分布等多项行为参数的变化。结果表明:斑马鱼对环境变化响应快速,游动速度短时间内急剧增大,之后下降再调整稳定至一定范围,变化趋势符合环境压力模型。游泳高度不断增大,暴露1 h后斑马鱼几乎全部集中到水箱上部,与暴露前水平差异显著。通讯行为参数平均距离和分散度在暴露后短时间内减小之后恢复到暴露前水平。通过解析斑马鱼的行为变化可以实现水体有机磷农药突发污染的早期预警。     

水体甲苯、乙苯和二甲苯对斑马鱼的毒性效应

以斑马鱼(Brachydanio rerio)为实验生物,采用半静态实验方法,研究了甲苯、乙苯和二甲苯的水生生态毒性效应.研究表明,水体中甲苯、乙苯和二甲苯对斑马鱼96h半致死浓度LC50分别为77.5、31.0和34.8mg·L-1,根据化学物质对鱼类毒性分级标准,3种物质均属中等毒性,其毒性大小顺序为:乙苯>二甲苯>甲苯.在最高暴露浓度下,斑马鱼均出现了剧烈、无序游动,并伴有抽搐等现象,其中暴露在甲苯中的斑马鱼行为改变更为严重.分析认为,3种物质对斑马鱼毒性大小与疏/亲水性有关,疏水性越强,对水生生物的毒性作用越大.     

1985年以来我国重大水体突发污染事件及在线生物监测的必要性分析

通过查阅和检索公开报道的期刊、报纸和网络,统计分析我国1985以来水体突发污染事件。1985—2015年间,我国水体突发污染事件年均发生数量总体变化呈现先动态增长后逐渐下降的趋势,其中2006年为水体突发性污染事件发生频次的转折点。导致水体突发性污染的主要原因包括企业违规排放、企业事故性泄漏、交通事故、自然因素和人为投毒等,污染方式多样。水体突发性污染的污染物种类包括化学品、污水(工业废水和生活污水)、油类、农药、重金属、生物污染物和其他不明污染物。鉴于水体突发性污染事件污染方式的多样性和污染物的复杂性,采用在线生物监测技术可实现对水体突发性污染事件在线监测与分析预警,已成为当前监测和评价水体突发污染事件有效手段。     

高效氯氰菊酯急性暴露中斑马鱼相关酶活性和基因表达变化

高效氯氰菊酯广泛地应用于农业生产及日常生活中的害虫防治,但对水生生物却毒性极高。为探究高效氯氰菊酯对斑马鱼的急性毒性,以总超氧化物歧化酶(总SOD)、过氧化氢酶(CAT)和乙酰胆碱酯酶(ACh E)活性以及相关的基因表达量变化为检测指标,研究其对斑马鱼成鱼的影响。急性毒性试验结果显示,高效氯氰菊酯对斑马鱼属剧毒物质,斑马鱼的急性中毒症状为身体蜷曲、抽搐,鳃盖扇动加快,游动能力减弱,间歇性出现无规律急速游动和撞壁行为。酶活测定结果显示,斑马鱼组织中总SOD、CAT和ACh E活性与高效氯氰菊酯呈现低浓度诱导、高浓度抑制的剂量效应关系;相关基因表达量的检测结果显示,高效氯氰菊酯会诱导斑马鱼肝脏、肠和脑中Sod1、Cat以及Ache的m RNA表达上调。研究表明,高效氯氰菊酯的神经毒性和氧化损伤共同造成了斑马鱼的中毒甚至死亡。     

麝香酮和镉单一与复合污染对金鱼藻的生态毒理效应研究

为从生物化学角度探讨一种新型污染物———麝香酮与镉(Cd)单一和复合污染的生态毒理效应,以金鱼藻(Ceratophyllum demersum L.)为研究对象,分析了不同浓度麝香酮和Cd在水中单一与复合污染对金鱼藻叶片中抗氧化系统酶,包括超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT),脂质过氧化最终产物丙二醛(MDA),可溶性蛋白(SP)和叶绿素含量的影响.结果表明:在单一麝香酮和Cd暴露下,SOD活性第1天均显著降低,而第7天在低浓度污染物的胁迫下呈升高趋势;金鱼藻受麝香酮和Cd胁迫的第1天,POD酶活性分别呈升高和降低趋势;麝香酮浓度为0.05mg·L-1或Cd浓度为0.01mg·L-1时,金鱼藻叶片中的CAT活性变化表现为显著的毒物兴奋作用;用两种污染物单一或复合处理第7天,金鱼藻叶片中的MDA和叶绿素含量可以作为评价麝香酮或/和Cd污染水体环境的敏感指标;SP在这两种污染物胁迫下处于能量及脂蛋白的补偿和应激蛋白的合成两方面的得失平衡过程中,故其含量与处理浓度之间无显著相关关系;复合污染中低浓度的麝香酮和Cd复合对金鱼藻表现为拮抗作用,高浓度的复合表现为相加或协同作用.     

不同汲取液在正渗透膜处理垃圾渗滤液过程中的作用

以垃圾渗滤液处理过程中的膜生物反应器(Membrane Bio-Reactor,MBR)出水作为研究对象,采用正渗透膜技术对其进行过滤,对比选择碳酸氢铵和乙二胺四乙酸(Ethylene Diamine Tetraacetic Acid,EDTA)-锌钠两种汲取液中性能较好的进行中试实验。研究了两种汲取液的不同浓度及膜朝向对膜通量的影响,检测了两种汲取液长时间运行所能达到的回收率,分析了两种汲取液的污染物截留率,用斑马鱼胚胎评估了垃圾渗滤液经两种汲取液处理后的生物毒性。结果表明:膜通量随着汲取液浓度增加而增加;在减压渗透(Pressure Reduced Osmosis,PRO)模式下的通量较正渗透(Forward Osmosis,FO)模式高,但污染较严重;碳酸氢铵和EDTA-锌钠在PRO和FO模式下的回收率分别为86.6%、91.6%和66.5%、71.2%;两种汲取液处理后的污染物截留率相差无几,都在98%以上;斑马鱼胚胎暴露于纯水、碳酸氢铵、EDTA钠盐汲取液处理后的水和垃圾渗滤液MBR出水中三天之后存活率为81%、76%、68%和0;实验说明相比于EDTA-锌钠,碳酸氢铵性能较好,适合进行下一步中试试验。     

双酚A对斑马鱼幼鱼神经递质和神经行为的影响

环境浓度水平下双酚A(BPA)暴露对生物体的毒性效应受到广泛关注。以早期发育阶段斑马鱼为模型,评价了环境浓度下BPA暴露对斑马鱼幼鱼运动行为的影响,并探讨了可能的作用机制。将斑马鱼胚胎暴露于不同浓度BPA(0、1、3、10和30"g·L-1)后,斑马鱼幼鱼的整体平均运动速率显著降低。低浓度组幼鱼在持续光照条件下的运动行为显著降低,同时5-羟色胺受体(htr1a)的转录水平增加十分显著,表明BPA可能通过5-羟色胺受体对斑马鱼的运动行为产生影响。而高浓度组幼鱼在第2个黑暗刺激周期的活动过度受到抑制,同时多巴胺受体(d1r)的转录水平显著降低,表明BPA可能通过多巴胺受体影响斑马鱼对外界刺激的响应。HPLC分析结果表明,5-羟色胺和多巴胺神经递质含量在所有浓度组均显著升高。进一步分析与早期神经发育(wnt1,shha)、单胺类递质神经元分化(lmx1a,nr4a2和syn2a)以及递质合成(tph1b,th)相关的基因和蛋白水平,发现神经递质含量的升高可能是由于BPA促进了斑马鱼胚胎早期神经发育和单胺类递质神经元的分化。综上,环境浓度下BPA暴露即可对斑马鱼的运行行为产生影响,提示BPA污染很可能对生态环境及人体健康产生潜在的危害。     

氯化镉、灭多威和硝基苯对日本青鳉(Oryzias latipes) 行为抑制的生物应急监测

研究了氯化镉、灭多威和硝基苯对孵化以后7d左右日本青鳉(Oryzias latipes)行为毒性。结果表明,在不同污染物中,随暴露浓度的增加,第1尾日本青鳉产生行为抑制的时间逐渐缩短,并且半数行为抑制时间(time ofhalf behavior inhibition,THBI,Y)随暴露浓度(X)呈现幂指数关系Y=aXb,其中20相似文献   

Behavioural toxicity in zebrafish (Danio rerio) exposed to waterborne zinc and chromium(VI)

This study is to investigate the behavioural responses of zebrafish to the toxic effects of waterborne zinc and chromium(VI). Swimming performance of fish was tracked by a real-time toxicity bio-monitoring system and transformed into data to calculate individual and fish school behavioural endpoints. Behavioural responses under metals were in accordance with the Stepwise Behavioural Response model. Significant and concentration-dependent effects on swimming speed and turning times were found at concentrations equal to or higher than 3.5 mg L^-1 for zinc and 0.7 mg L^-1 for chromium. Swimming height significantly declined in concentrations equal to or higher than 3.5 mg L^-1 under zinc exposure, while for the chromium treatment, it significantly increased in lower concentration exposures and decreased in higher concentration exposures. Average distance and dispersion of fish school decreased at the beginning but there were no obvious changes during the whole exposure period. Behavioural responses under metal exposures were time-dependent: avoidance (increased speed and turning times and decreased average distance and dispersion) might be the first response and followed by height changes. Changes in behavioural endpoints ‘swimming speed and height’ can be used as early stress responses for acute aquatic metal contamination as part of ecological risk assessment.     

氯化镉对斑马鱼胚胎的发育毒性

为探讨重金属Cd对斑马鱼胚胎发育的毒性效应,将受精1h后(1hpf)的斑马鱼胚胎暴露于不同浓度的CdCl2溶液中,观察CdCl2处理对胚胎死亡、孵化及幼鱼畸形的影响。采用吖啶橙(AO)染色,定性观察胚胎细胞凋亡情况;以活性氧(ROS)荧光探针DCFH-DA染色法检测胚胎ROS水平,TBA比色法测定胚胎脂质过氧化水平,DTNB比色法测定还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)水平。结果表明,10.0～30.0mg·L-1CdCl2浓度依赖性地诱导斑马鱼胚胎死亡和幼鱼畸形,胚胎孵化率亦降低。CdCl2处理引起斑马鱼胚胎心脏水肿,尾部弯曲和胚胎发育阻滞。胚胎半数致死浓度(LC50)为18.9mg·L-1,R2=0.973,幼鱼半数致畸浓度(EC50)为13.7mg·L-1,R2=0.967。20.0mg·L-1CdCl2处理组ROS水平、MDA含量明显升高,GSH/GSSG比值明显降低(P<0.01)。20mg·L-1CdCl2处理后,胚胎头部和尾部可见大量细胞凋亡。10mg·L-1N-乙酰半胱氨酸(NAC)与20mg·L-1CdCl2共同处理组斑马鱼胚胎的死亡率和畸形率明显降低,孵化率明显升高,ROS水平、MDA含量以及GSH/GSSG比值趋于正常。以上结果说明,CdCl2暴露对斑马鱼胚胎发育的毒性效应可能与CdCl2诱导的氧化应激相关。     

PFOA对斑马鱼胚胎发育、行为和DNA损伤的毒性研究

全氟辛酸(PFOA)是一种分布广泛的环境持久性有机污染物,在野生动物与人体内普遍被检出。目前PFOA发育毒性的特点和机制尚未阐明,已有的研究显示,PFOA毒性与受试物种及性别密切相关。因此,利用不同物种进行PFOA毒性研究对阐明其毒性机制十分重要。本研究选用了斑马鱼这种理想的脊椎动物模型,考察了PFOA暴露对其胚胎发育的自主运动、心跳、行为、细胞凋亡和DNA损伤的影响。研究发现,始于6hpf的PFOA暴露会导致斑马鱼胚胎自主运动异常,心率降低,且具有一定的剂量依赖性;6～24hpf的高浓度的PFOA暴露(>414.0mg·L-1)会导致胚胎发生显著的细胞凋亡,凋亡主要出现在眼部、头部、心脏和尾部。较高浓度的PFOA暴露(165.6mg·L-1)会使仔鱼的光刺激应激行为模式发生变化。此外,PFOA暴露会致使斑马鱼发生DNA损伤,且损伤程度随PFOA浓度的升高而加重,表明PFOA具有一定的基因毒性。上述结果表明,PFOA对斑马鱼胚胎具有发育毒性,具体表现为自主运动异常,心率降低和行为反应能力变弱,同时伴随畸形、细胞凋亡和DNA损伤。     

Wirkung subakuter PCB-Exposition (Aroclor 1254) auf Sauerstoffverbrauch, Schwimmbewegung und Biotransformation (GST-Aktivität) des Karpfens (Cyprinus carpio)

Objective and Background

PCB (polychlorinated biphenyle) are typical man-made environmental pollutants that cause a broad spectrum of effects in vertebrates. Although a lot has been studied about the toxic effects of xenobiotic substances on aquatic organisms, their subacute effects are not yet well known. Fish occupies a central position in freshwater food webs and therefore, carp was chosen to be our test organism. The aim of our study was the investigation of subacute effects of Aroclor 1254 (22μg ^l?1) on respiration, swimming activity, and biotransformation, allowing discussion of changed interaction between the available energy resources.

Methods

The respiration experiments under controlled laboratory conditions were run for 29 days (5 d before, 16 d with and 8 d after chemical exposure) with exposed carp compared to the non-exposed fish. Furthermore, the BehavioQuant system quantitatively monitors the positions of each individual fish before (8 d) and during (21 d) PCB exposure and swimming activity (number of horizontal turnings s^?1) of animals was calculated. Thereafter, liver samples were taken from animals for analysis of the phase 2 enzyme activity (glutathione-S-transferase). In the respiration experiments were 6 exposure, 6 controll, and 3 solubilizer controll groups (12 animals each group); in the behavioral experiments were 9 exposure, 6 controll- und 3 solubilizer controll groups (6 animals each group), and in the enzyme activity measurements were 9 exposure, 6 controll and 3 solubilizer controll groups (6 animals each group) examined.

Results and Discussion

A clearly increased (33%) oxygen consumption due to the PCB-exposure is found to be reversible; after the exposure period the respiration of carp shows a level comparable to the oxygen consumption during non-exposure time. By evaluating quantitative behavioral parameters of animals, it becomes evident that the exposure to PCB also causes a reversible change in their swimming behavior. Chemical stress leads to a decrease of mean daily swimming activity combined with an increase of the mean number of turnings during the night. Thereafter, the swimming activity shifts to the circadian swimming behavior under control conditions. Furthermore, our measurement of soluble and microsomal glutathione-S-transferase activity of fish liver shows a significant elevation after exposure period.

Conclusion

Our results prove that it was feasible to detect sublethal effects of PCB-mixture on all parameters under these conditions successfully. Our findings imply that fish are able to cope with the chemicals and we purse the hypothesis that the higher physiological energy demand caused by increased activity of enzymes, which are involved in biotransformation of foregin substances, may be related to a higher respiration of fish stressed by xenobiotics.

Recommendation and Outlook

Further experiments should investigate the effects of PCB on ecophysiological parameters of carp fed with exposed natural food allowing discussion of ecological consequences.     

The influence of dissolved oxygen and carbon dioxide on fish schooling behavior

Slow reduction of dissolved oxygen concentrations or slowly increased carbon dioxide (reduced pH) did not cause measurable changes in the density, nearest neighbor orientation, or the swimming speed of experimental schools of the northern anchovy Engraulis mordax, until near-lethal levels were reached. Rapid reductions of oxygen or pH, however, caused significant increases in average swimming velocity. Positive reactions were correlated to rapid reductions of no more than 0.55 mg O₂/l or 0.25 pH units. These responses are related to the hypothesis that metabolic reductions of environmental dissolved oxygen and/or pH may influence the internal structure and behavior of fish schools.     

Benefit of suites of defensive behavior induced by predator chemical cues on anuran tadpoles, Hyla japonica

When predator chemical cues are present, low activity of prey is a commonly seen defensive behavior. However, few studies have explored the functional implications of the defensive behaviors and, thus, elucidated the possible linkages between behavioral responses and its consequences. In this study, we experimentally investigated how behavioral responses of Hyla japonica tadpoles to predator chemical cues affect vulnerability to a dragonfly nymph Anax parthenope julius. The frequency of tadpoles attacked by dragonfly nymphs was lower with chemical cues of predator was present than without chemical cues, and most of attacks occurred when tadpoles were mobile. When tadpoles were exposed to chemical cues, on the other hand, their swimming speed was quicker and swimming distance was longer, respectively, and the rates of being approached of the swimming tadpoles by dragonfly nymph was lower than those not exposed to chemical cues. We found that the tadpoles are induced by predator chemical cues not only to generally lower activity but also to swim in bursts as additional behavior and that the suite of their behavioral responses reduce the vulnerability against dragonfly nymph. Tadpoles can receive information about the predation risks by chemical cues and adjust their defensive behavior accordingly.