Grintzalis Konstantinos, Dai Wenkui, Panagiotidis Konstantinos, Belavgeni Alexia, Viant Mark R
School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom.
School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom; Department of Biology, Section of Animal Biology, School of Natural Sciences, University of Patras, Patras 26500, Greece.
Ecotoxicol Environ Saf. 2017 May;139:352-357. doi: 10.1016/j.ecoenv.2017.02.002. Epub 2017 Feb 23.
Phenotypic markers of animal health form an essential component of regulatory toxicology. Immobilisation of neonate water fleas - Daphnia magna - as a surrogate measure of their mortality following exposure to a chemical for 24-48h forms the basis of the internationally utilised OECD acute toxicity test 202. A second important marker of animal physiology and health is feeding rate, which in Daphnia is determined by measuring the algae feeding rate. Given the widespread use of OECD test 202 for acute toxicity as well as the quantification of feeding rate in toxicological studies of daphniids, significant benefits could result from miniaturising this assay. In particular, miniaturisation would use fewer animals, less media and chemicals, less laboratory space and make the tests more compatible with automation, and therefore could result in considerable time savings. Furthermore, miniaturising phenotypic markers to the ultimate level of a single animal per well would facilitate multiple measurements of other phenotypic markers, such as behavioural responses, which could be integrated at the individual level. In this study we used a wide range of exposure vessels to evaluate the impacts of systematically varying total media volume, surface to volume ratio and animal density for the acute toxicity testing of cadmium. We demonstrate that Daphnia acute toxicity tests using single animals within 24- or 48-well plates produce equivalent results as for traditional test configurations, for different chemicals. Considering algae feeding rates by Daphnia, we studied the impacts of varying algae concentration, total volume and animal density. After having demonstrated that multiwell plates can again yield equivalent test results as traditional experimental setups, we used miniaturised test vessels to show the impact of metals on the feeding activity on daphniids for both neonates and adult animals. Overall we confirm the feasibility of a multiwell approach for Daphnia toxicity testing that requires less time and materials than a traditional assay and can provide phenotypic characterisation at a single animal level.
动物健康的表型标记是监管毒理学的重要组成部分。将新生水蚤（大型溞）固定化，作为其接触化学品24至48小时后死亡率的替代指标，是国际上通用的经合组织急性毒性试验202的基础。动物生理和健康的另一个重要标记是摄食率，对于大型溞，摄食率通过测量藻类摄食率来确定。鉴于经合组织试验202在急性毒性测试以及大型溞毒理学研究中摄食率量化方面的广泛应用，将该试验小型化可能会带来显著益处。特别是，小型化将减少动物使用数量、培养基和化学品用量、实验室空间需求，并使测试更易于自动化，从而可节省大量时间。此外，将表型标记小型化至每孔仅一只动物的最终水平，将便于对其他表型标记进行多次测量，如行为反应，这些反应可在个体水平上进行整合。在本研究中，我们使用了多种暴露容器，以评估系统改变总培养基体积、表面积与体积比和动物密度对镉急性毒性测试的影响。我们证明，在24孔或48孔板中使用单只动物进行大型溞急性毒性测试，对于不同化学品，其结果与传统测试配置相当。考虑到大型溞的藻类摄食率，我们研究了改变藻类浓度、总体积和动物密度的影响。在证明多孔板可再次产生与传统实验设置相当的测试结果后，我们使用小型化测试容器展示了金属对新生和成年大型溞摄食活动的影响。总体而言，我们证实了多孔板方法用于大型溞毒性测试的可行性，该方法比传统试验所需时间和材料更少，且可在单只动物水平上提供表型特征描述。
