Department of Animal Biology (Vertebrates) & Biodiversity Research Institute (IRBio), University of Barcelona, E-08028 Barcelona, Spain.
Sci Total Environ. 2013 Apr 1;449:9-19. doi: 10.1016/j.scitotenv.2013.01.012. Epub 2013 Feb 10.
The requirements of the Water Framework Directive suggest the need for further research to test and develop sensitive tools that will allow freshwater managers to detect impacts on fish communities. Diagnostic refinement often encompasses the use of lethal diagnostic tools that are incompatible with the conservation of native ichthyofauna. Here we determine the metal concentration and the pathological response of Squalius laietanus exposed to sewage discharges in the Ripoll river (north-eastern Spain), and compare these findings with our previous studies on Barbus meridionalis using lethal and non-lethal diagnostic tools. Metals concentrations (Zn, Cu, Pb, Hg, Fe, Cd and Ni) were determined in liver and muscle. A complete blood cell profile (haematocrit, haemoglobin, differential leukocyte count, erythrocytic nuclear abnormalities, erythrocytes in division and the development stage of erythrocytes) was used as a non-lethal diagnostic tool to determine early warning signs of disease in these two fish species. As the reference range for these haematological variables is lacking, liver histology, calculation of body condition (CF) and organosomatic indices (HSI and GSI) were employed to support the findings of the blood analyses. Compared to our previous results on B. meridionalis, S. laietanus appeared to have fewer pathological responses than B. meridionalis under the environmental conditions measured and the fish size range examined in this study. Both species showed a similar bioaccumulation pattern, but B. meridionalis stored high Hg and Cu concentrations in muscle and liver, respectively. Hg, Cu and Pb concentrations in fish tissues exceeded the thresholds of European and Spanish legislation. Our findings pinpoint the potential suitability of the blood variables determined in the health diagnoses of these species. Further research will be necessary to establish the natural variability of these and other haematological variables to convert haematology into a sensitive and useful non-lethal diagnostic tool in wild fish populations.
《水框架指令》的要求表明，需要进一步研究测试和开发敏感工具，以便淡水管理者能够检测到对鱼类群落的影响。诊断细化通常包括使用与保护本地鱼类区系不兼容的致命诊断工具。在这里，我们确定了 Squalius laietanus 在 Ripoll 河（西班牙东北部）受到污水排放影响时的金属浓度和病理反应，并将这些发现与我们之前使用致命和非致命诊断工具对 Barbus meridionalis 的研究进行了比较。金属浓度（Zn、Cu、Pb、Hg、Fe、Cd 和 Ni）在肝脏和肌肉中进行了测定。完整的血细胞谱（红细胞压积、血红蛋白、白细胞分类计数、红细胞核异常、红细胞分裂和红细胞发育阶段）被用作非致命的诊断工具，以确定这两种鱼类疾病的早期预警信号。由于这些血液学变量的参考范围缺失，因此采用肝脏组织学、身体状况（CF）和器官体指数（HSI 和 GSI）计算来支持血液分析的结果。与我们之前对 B. meridionalis 的研究结果相比，在本研究中测量的环境条件和检查的鱼类大小范围内，S. laietanus 的病理反应似乎比 B. meridionalis 少。这两个物种表现出相似的生物积累模式，但 B. meridionalis 在肌肉和肝脏中分别储存了高浓度的 Hg 和 Cu。鱼类组织中的 Hg、Cu 和 Pb 浓度超过了欧洲和西班牙立法的阈值。我们的研究结果指出了这些物种健康诊断中确定的血液变量的潜在适用性。需要进一步的研究来确定这些和其他血液学变量的自然变异性，以便将血液学转化为野生鱼类种群中敏感和有用的非致命诊断工具。
