Laboratorio de Inmunología, Departamento de Ciencias Básicas, Universidad Nacional de Lujan, B6700ZBA Luján, Argentina; Instituto de Ecología y Desarrollo Sustentable (INEDES), Universidad Nacional de Luján - CONICET, P.O. Box 221, B6700ZBA Luján, Argentina.
Instituto de Ecología y Desarrollo Sustentable (INEDES), Universidad Nacional de Luján - CONICET, P.O. Box 221, B6700ZBA Luján, Argentina; Programa de Ecofisiología Aplicada (PRODEA), Departamento de Ciencias Básicas, Universidad Nacional de Lujan, P.O. Box 221, B6700ZBA Luján, Argentina.
Ecotoxicol Environ Saf. 2021 Jan 15;208:111639. doi: 10.1016/j.ecoenv.2020.111639. Epub 2020 Nov 11.
Cnesterodon decemmaculatus is a Neotropical teleost fish frequently used in ecotoxicological evaluations, whose biology has been thoroughly studied. Although there is considerable information on its response to different toxicants, no range of reference values has been so far established for the different biological parameters proposed as biomarkers of effect or exposure. Moreover, no study has yet examined the possible influence of the metabolic status of the exposed animals on their response to toxic stress. Therefore, the aim of this work was to provide a first baseline for a set of bioenergetic biomarkers in C. decemmaculatus adults exposed to a control medium under previously standardized conditions, and to assess their possible intrinsic seasonal variability. The responses of the biomarkers obtained from the controls were contrasted with those from the reference toxicant (Cadmio-Cd) and receiving waters (surface waters of the Reconquista River RR, Buenos Aires Province, Argentina). We conducted four 12-day assays (one in each season) of exposure to control media, (reconstituted moderate hard water, MHW) and two assays of exposure to Cd in MHW and surface river water (RR) in both summer and autumn. The variables recorded were: Food intake (In), fecal production (F), specific assimilation (A) and cumulative mortality, oxygen extraction efficiency (OEE), specific metabolic rate (SMR), ammonia excretion (N), ammonia quotient (AQ) and scope for growth (SFG). The seasonal variation shown by some physiological parameters, points to the need for establishing a baseline obtained from standardized media, preferably on a seasonal basis. Moreover, SFG and A appeared as the most sensitive biomarkers, emphasizing the importance to consider the metabolic status of the test organisms for the appropriate interpretation of results from ecotoxicological studies performed under controlled experimental conditions. The obtained results provide useful information on C. decemmaculatus as model species in ecotoxicological bioassays involving biomarkers of early effect.
圆口铜鱼是一种新热带鱼类，常用于生态毒理学评估，其生物学特性已得到深入研究。虽然已经有相当多的关于其对不同毒物的反应的信息，但到目前为止，还没有为不同的生物学参数建立参考值范围，这些参数被提议作为效应或暴露的生物标志物。此外，还没有研究检查暴露动物的代谢状态对其对有毒应激的反应的可能影响。因此，本工作的目的是为一组新热带鱼类圆口铜鱼成鱼的生物能量学生物标志物提供一个基准，这些生物标志物在先前标准化条件下暴露于对照介质中，并评估它们可能存在的内在季节性变化。从对照中获得的生物标志物的反应与参考毒物（镉-Cd）和接收水（阿根廷布宜诺斯艾利斯省 Reconquista 河的地表水 RR）的反应进行了对比。我们进行了四个为期 12 天的对照介质（重碳酸盐硬度适中的水，MHW）暴露实验和两个 Cd 在 MHW 和地表水（RR）中的暴露实验，每个季节进行一次实验。记录的变量包括：摄食量（In）、粪便产量（F）、特定同化率（A）和累积死亡率、耗氧效率（OEE）、特定代谢率（SMR）、氨排泄量（N）、氨比（AQ）和生长范围（SFG）。一些生理参数的季节性变化表明，需要建立一个从标准化介质获得的基线，最好是基于季节性的。此外，SFG 和 A 似乎是最敏感的生物标志物，这强调了在受控实验条件下进行生态毒理学研究时，需要考虑测试生物的代谢状态，以便对结果进行适当解释。所获得的结果为圆口铜鱼作为涉及早期效应生物标志物的生态毒理学生物测定中的模型物种提供了有用的信息。
