Cátedra de Diversidad Animal II, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Av. Vélez Sársfield 299, Córdoba, Argentina.
Arch Environ Contam Toxicol. 2013 Feb;64(2):281-90. doi: 10.1007/s00244-012-9826-8. Epub 2012 Nov 4.
The potential threat to animal reproduction by contaminated freshwater systems posed the necessity to identify and develop bioindicators and biomarkers to be used for screening and evaluation of the effects in organisms. The main goal of this work was to determine, through histological analyses and changes in gonopodium morphology, whether a freshwater system polluted by anthropogenic activities-sewage, agricultural, and industrial-could cause alterations at the organ level. We also propose the live-bearing fish, Jenynsia multidentata, as a species suitable to study the effects of contaminated aquatic environments. We compared male fish sampled at two different stations in Suquía River basin (Córdoba, Argentina), both differing in degree of pollution, through liver and testis histology and gonopodial morphometric parameters. The water quality, based on the physicochemical characteristics of the studied stations, varied markedly with a decrease in water quality at the downstream site (station 2). At the highest polluted area, detrimental effects on liver and testis were evidenced on histological analysis. Male individuals from station 2 also presented noticeable structural changes of the anal fin, such as a straight gonopodium and abnormal tip area. The present results demonstrate that a freshwater system polluted by the impacts of anthropogenic activities has detrimental effects to J. multidentata. The alterations registered in individuals from the polluted station indicate an impairment of male reproductive performance and imply a risk for other live-bearing species as well as the entire biodiversity. We consider J. multidentata a sentinel species that is useful to evaluate the potential risk present in the studied basin not only to itself but to other species as well.
受污染的淡水系统对动物繁殖构成的潜在威胁，使得有必要识别和开发生物标志物，用于筛选和评估对生物的影响。本工作的主要目的是通过组织学分析和生殖肢形态的变化，确定受人为活动（污水、农业和工业）污染的淡水系统是否会导致器官水平的改变。我们还提出了产仔鱼 Jenynsia multidentata 作为研究受污染水生环境影响的合适物种。我们比较了在 Suquía 河流域（阿根廷 Córdoba）两个不同地点采集的雄性鱼类，这两个地点的污染程度不同，通过肝脏和睾丸组织学以及生殖肢形态计量学参数进行比较。水质根据研究地点的物理化学特征而有明显差异，下游地点（第 2 站）的水质下降。在污染最严重的地区，组织学分析显示对肝脏和睾丸有不利影响。来自第 2 站的雄性个体的分析鳍也表现出明显的结构变化，如生殖肢变直和异常尖端区域。本研究结果表明，受人为活动影响的淡水系统对 J. multidentata 有不利影响。污染地点个体的变化表明雄性生殖性能受损，这对其他产仔物种以及整个生物多样性构成了风险。我们认为 J. multidentata 是一种有用的指示物种，可用于评估研究流域中存在的潜在风险，不仅对自身，而且对其他物种也是如此。
