First Ecotoxicologial Evaluations in Nemtaomorpha: Can Chordodes nobilii be considered a good bioindicator?

ACHIORNO C.; DE VILLALOBOS C.; FERRARI L.

Virginia

Simposio; The 87th Annual Meeting of the American Sopciety of Parasitologists. International Nematomorpha Symposium.; 2012

American Sopciety of Parasitologists

FIRST ECOTOXICOLOGICAL EVALUATIONS IN NEMATOMORPHA. CAN CHORDODES NOBILII BE CONSIDERED A GOOD BIOINDICATOR? C. Achiorno, Universidad Nacional de La Plata C. de Villalobos, Universidad Nacional de La Plata L. Ferrari, Universidad Nacional de Luján The present study was carried out based on the hypothesis that environmental stress affects Gordiida infective capacity as well as their numbers in their aquatic habitat. The need to find neotropical native bioindicators is also considered in this study. For the first time, assay protocols were designed to evaluate the effect of pollutants in the free-living stages of Chordodes nobilii, in order to determine if this Nematomorpha species is a good bioindicator of contamination in freshwater environments. Endpoints compatible with their life cycle were selected, and for two of them, an index which evaluates the infective capacity of parasites was put into practice for the evaluation of the effect of environmental and anthropic variables. Sensitivity of C. nobilii to temperature, pesticides and referent toxics was determined. From the results obtained during the experimental period, it was possible to conclude that preparasitic stages of C. nobilii present not only a high sensitivity to the used toxics but also a wide range of thermic tolerance under laboratory conditions. Therefore, the protocols designed for such end could be carried out and were repeatable and reliable and have subsequently been validated for the ecotoxicological evaluation of Gordiida species. Finally, it can be considered that C. nobilii presents many of the necessary characteristics to be considered a bioindicator species. Studies to correlate the presence of this species in different habitats according to water quality are being held in Argentina. The results obtained together with the ecological value of C. nobilii, which links aquatic and terrestrial ecosystems occupying different levels in the trophic web, strengthen the idea of considering this species as a diagnostic organism for ecotoxicological evaluations and as a contamination bioindicator.