Graduate Program in Comparative Biology, Maringá State University, Paraná, Brazil.
Graduate Program of Professional Mastering in Ecology of Continental Aquatic Environments, Maringá State University, Paraná, Brazil.
Sci Total Environ. 2020 Oct 10;738:140339. doi: 10.1016/j.scitotenv.2020.140339. Epub 2020 Jun 18.
Studies have demonstrated the role of acanthocephalan as environmental bioindicators. The dynamics in the parasite-host relationship that define the patterns of distribution of trace metals in parasites and, in its host, are extremely variable. In addition, the neotropical region, which is a major maintainer of the biodiversity of fish and parasites, remains little explored in this subject. Therefore, our objective was to analyze and compare the concentration of Cadmium (Cd) in the tissues of Prochilodus lineatus and Serrasalmus marginatus collected from Baía and Paraná rivers, as well as to assess the use of acanthocephalan as environmental bioindicators of pollution and their Cd bioaccumulation capacity. We collected 53 fish, 20 specimens of Prochilodus lineatus from Paraná River and 17 from Baía River, in addition to 16 specimens of Serrasalmus marginatus from Baía River, in September 2017 and March 2018. Tissues of the fish along with their parasites were subjected a Cd concentration analysis by Atomic Absorption Spectroscopy. The results revealed that the parasites had higher concentrations than all the tissues of S. marginatus, P. lineatus from Baía River and Paraná River. The high Cd concentrations in these parasites derived from their bioaccumulation capacity, because of the absorption of nutrients directly from the intestinal content of the fish through the tegument, as well as for the presence of Cd on the surface waters of Praná River floodplain. Besides that, the Coefficient of Spearman Rank Correlation showed that the infrapopulation size seems to affect Cd bioaccumulation in the parasites, smaller infrapopulations demonstrate a higher accumulation capacity compared to the larger ones. With that, we concluded that the two acanthocephalans species analyzed in this study have a good capacity for Cd accumulation, and can be used as accumulation indicators of trace-metal pollution. Accumulation indicators provide important information on the biological availability of pollutants.
研究表明，刺头虫可作为环境生物标志物。寄生虫与宿主之间的动态关系决定了痕量金属在寄生虫和宿主中的分布模式，而这种关系极具多变性。此外，作为鱼类和寄生虫生物多样性的主要维护者，新热带地区在这一领域的研究也相对较少。因此，我们的目的是分析和比较巴伊亚河和巴拉那河采集的 Prochilodus lineatus 和 Serrasalmus marginatus 组织中的镉 (Cd) 浓度，并评估刺头虫作为污染环境生物标志物及其 Cd 生物累积能力的应用。我们于 2017 年 9 月和 2018 年 3 月，从巴拉那河采集了 20 尾 Prochilodus lineatus 和 17 尾来自巴伊亚河的 Prochilodus lineatus，从巴伊亚河采集了 16 尾 Serrasalmus marginatus。通过原子吸收光谱法对鱼类组织及其寄生虫的 Cd 浓度进行了分析。结果表明，与所有 Serrasalmus marginatus 组织以及来自巴伊亚河和巴拉那河的 Prochilodus lineatus 组织相比，寄生虫的 Cd 浓度更高。这些寄生虫具有较高的 Cd 浓度，这是因为它们具有生物累积能力，可通过体壁直接从鱼类肠道内容物中吸收营养物质，同时，由于巴拉那河泛滥平原地表水含有 Cd。此外，Spearman 秩相关系数表明，亚种群规模似乎影响寄生虫对 Cd 的生物累积，较小的亚种群比较大的亚种群具有更高的累积能力。综上所述，我们得出结论，本研究分析的两种刺头虫具有良好的 Cd 累积能力，可作为痕量金属污染的累积指标。累积指标提供了有关污染物生物可利用性的重要信息。
