Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany.
Department of Experimental Molecular Imaging, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany.
Sci Total Environ. 2016 Feb 1;543(Pt A):135-139. doi: 10.1016/j.scitotenv.2015.11.020. Epub 2015 Nov 12.
Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals.
鱼类是评估水质的重要指示生物，在生态毒理学研究中起着核心作用。形态计量学（例如，福氏系数）和体躯指数（例如，肝体比和性腺体比）特别重要，可用于评估鱼类种群对环境条件或污染的健康和适应性。体躯指数的标准测量方法具有侵入性，根据定义需要牺牲被检查的动物，从而禁止进行纵向研究和对野外捕获的动物进行重新安置。作为一种潜在的解决方案，在本研究中，我们提出使用微计算机断层扫描（μCT）作为成像方式，对暴露于不同沉积物悬浮液中的虹鳟鱼（Oncorhynchus mykiss）进行非侵入性断层扫描成像。我们在此证明，μCT 可作为一种可靠测量不同器官体积的工具，然后可以将其应用于计算体躯指数时替代器官重量。据我们所知，这项研究首次在虹鳟鱼的生态毒理学研究中报告了 μCT 分析的结果。它有可能极大地增加用鱼类进行的实验的信息价值，并有可能通过促进同一个体内的纵向研究，减少研究时间效应所需的动物数量。
