Erythrocyte Nuclear Abnormalities in Astyanax lacustris in Response to Landscape Characteristics in Two Neotropical Streams

Abstract

The objective of this research was to evaluate land use and occupation in the landscape surrounding two neotropical streams of the Upper Paraná River in Brazil and to investigate if the water from these streams induces erythrocyte nuclear abnormalities in Astyanax lacustris. We observed that the areas surrounding the streams are predominantly used for agricultural purposes (73.46% of the total area), followed by buildings (15.21%). Only 8.78% of the area consisted of forest fragments. We observed higher frequencies of micronuclei in erythrocytes of A. lacustris exposed to water from impacted sites (IMP) compared with less impacted sites and the negative control (NC) (p < 0.05). Analysis of nuclear alterations in A. lacrustis erythrocytes showed significant differences in the frequency of notched nuclei and nuclear pyknosis only between the NC and the IMP sites (p < 0.05). Our results indicate that water from the most impacted sites of the microbasin can induce mutagenic and genotoxic effects in A. lacustris.

Effect of dosage of orally administered 17α-methyltestosterone on sex reversion of the yellowtail tetra Astyanax lacustris (Lütken, 1875)

“…The presence and increased frequency of micronuclei in erythrocytes is an indicator of genetic damage, likewise, nuclear alterations in erythrocytes may be an indicator of cytotoxic effect, both caused in fish exposed to environmental and chemical contaminants (Samanta and Dey, 2012;Ribeiro et al, 2014;Viana et al, 2018). Regarding the toxicity of MT in Astyanax, other studies observed an increased frequency of NA when adult individuals of another sister species, A. bimaculatus, were treated with feed supplemented with 60 mg/kg of this hormone for 28 days (Rivero-Wendt et al, 2013a) or by immersion with 1 mg for 96 hours (Rivero-Wendt et al, 2013b).…”

Are there differences in the frequency of micronuclei in Astyanax lacustris in relation to sex, mass and length?

“…The environmental health assessment of aquatic ecosystems using fish as biomarkers (DNA damage) has been increasingly recommended due to responses to the effects of contamination on the aquatic environment by genotoxic agents (Viana et al, 2017;Lima et Research, Society and Development, v. 9, n. 8, e181985151, 2020 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10. 33448/rsd-v9i8.5151 al., 2018;Hussain et al, 2019).…”

“…Astyanax lacustris (Lutken, 1875) (Characiformes, Characidae) is a species that have been widely used as an environmental bioindicator in both in situ and ex situ studies in the assessment of genotoxic effects (Trujillo-Jiménez et al, 2011;Chehade et al, 2014;Dourado et al, 2016;Viana et al, 2017;2018;Milanin et al, 2018;Sposito et al, 2019). And in this context, it is important to note that recently Lucena and Soares (2016) proposed the unification of the species A. asuncionensis, A. altiparanae and A. lacustris, considered synonymous, under the name Astyanax lacustris (Lutken, 1875).…”