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1.
Commun Biol ; 4(1): 74, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462402

RESUMO

The marbled crayfish (Procambarus virginalis) represents a very recently evolved parthenogenetic freshwater crayfish species that has invaded diverse habitats in Europe and in Madagascar. However, population genetic analyses have been hindered by the homogeneous genetic structure of the population and the lack of suitable tools for data analysis. We have used whole-genome sequencing to characterize reference specimens from various known wild populations. In parallel, we established a whole-genome sequencing data analysis pipeline for the population genetic analysis of nearly monoclonal genomes. Our results provide evidence for systematic genetic differences between geographically separated populations and illustrate the emerging differentiation of the marbled crayfish genome. We also used mark-recapture population size estimation in combination with genetic data to model the growth pattern of marbled crayfish populations. Our findings uncover evolutionary dynamics in the marbled crayfish genome over a very short evolutionary timescale and identify the rapid growth of marbled crayfish populations as an important factor for ecological monitoring.

2.
Ecotoxicol Environ Saf ; 208: 111645, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396165

RESUMO

The effects of chloridazon (Ch) and its metabolite chloridazon-desphenyl (Ch-D) at the environmentally relevant concentrations of 0.45 µg/L and 2.7 µg/L on signal crayfish Pacifastacus leniusculus were assessed in a 30-day exposure followed by a 15-day depuration period. Locomotion, biochemical haemolymph profile, oxidative and antioxidant parameters, and histopathology were evaluated. Crayfish exposed to Ch at 0.45 µg/L and 2.7 µg/L showed significantly (p < 0.01) higher CAT activity and GSH level in hepatopancreas and gill compared to controls. The concentration of Ch at 2.7 µg/L was associated with significantly (p < 0.01) higher levels of GLU, LACT, ALT, AST in haemolymph compared to controls. Chloridazon-desphenyl exposure at both tested concentrations caused significantly higher (p < 0.01) GLU, LACT, ALT, AST, NH3, and Ca in haemolymph; lipid peroxidation (TBARS) levels in hepatopancreas; and CAT activity and GSH level in hepatopancreas and gill. Alterations of structure including focal dilatation of tubules, increased number of fibrillar cells, and haemocyte infiltration in the interstitium were observed with 2.7 µg/L Ch and with both Ch-D exposures. Locomotion patterns did not vary significantly among groups. A 15-day recovery period was insufficient to restore normal physiological parameters in exposed groups. Chloridazon and its metabolite Ch-D exerts harmful effects on crayfish.


Assuntos
Astacoidea/efeitos dos fármacos , Herbicidas/toxicidade , Piridazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Astacoidea/fisiologia , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hemolinfa/citologia , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Hepatopâncreas/patologia , Herbicidas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piridazinas/metabolismo , Poluentes Químicos da Água/metabolismo
3.
Sci Total Environ ; 751: 141383, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882544

RESUMO

Pharmaceutically active compounds (PhACs) are ubiquitous in the aquatic environment worldwide and considered emerging contaminants. Their effects on growth, behavior, and physiological processes of aquatic organisms have been identified even at very low concentrations. Ecotoxicological investigations have primarily focused on single compound exposure, generally at a range of concentrations. In the natural environment, pollutants seldom occur in isolation, but little is known about the effects and risks of combinations of chemicals. This study aimed to investigate the effects of concurrent exposure to six psychoactive PhACs on locomotory behavior and life history traits of clonal marbled crayfish Procambarus virginalis. Crayfish were exposed to ~1 µg L-1 of the antidepressants sertraline, citalopram, and venlafaxine; the anxiolytic oxazepam; the opioid tramadol; and the widely abused psychostimulant methamphetamine. In the absence of shelter, exposed crayfish moved significantly shorter distances and at lower velocity and showed significantly less activity than controls. With available shelter, exposed crayfish moved significantly more distance, showed higher activity, and spent a significantly more time outside the shelter than controls. Molting, mortality, and spawning frequency did not vary significantly between the groups. Hemolymph glucose level did not vary among groups and was not correlated with observed behaviors. Results suggest that environmental concentrations of the tested compounds in combination can alter the behavior of non-target aquatic organisms as individual exposure of these compounds, which may lead to disruption of ecosystem processes due to their reduced caution in polluted conditions. Further research is needed using varied chemical mixtures, exposure systems, and habitats, considering molecular and physiological processes connected to behavior alterations.


Assuntos
Metanfetamina , Preparações Farmacêuticas , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Astacoidea , Ecossistema , Poluentes Químicos da Água/toxicidade
4.
Chemosphere ; : 128656, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33172666

RESUMO

Despite their low concentrations in many aquatic environments, evidence exists to suggest that herbicides do affect non-target organisms. Given that burrowing is a primary life-history trait in crayfish, herbicides could potentially have serious negative effects on these ecologically important freshwater macroinvertebrates. In this study, we exposed the red swamp crayfish Procambarus clarkii to terbuthylazine (a triazine) and metazachlor (a chloroacetanilide) at an environmental concentration of 2.0 µg/L for 28 days, and then observed their burrowing behaviour for two days. The metazachlor-exposed males excavated a greater number of burrows than the other tested groups, with comparable depths and volumes relative to individual specimen weight. The relative depth and volume of female burrows were identical in all groups. The natural habit of female crayfish of constructing deeper burrows than males was marginally significant in the control and META groups but was not significant for relative volume. The hypothesized adverse effects of chronic exposure to real environmental concentrations of herbicides were not documented in terms of either relative depth or volume. However, the increased number of burrows in metazachlor-exposed animals may mean that this invasive species will cause greater damage to embankments and river banks. The mechanisms behind these effects require closer study.

5.
Sci Rep ; 10(1): 19607, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177672

RESUMO

Screening of novel feedstuffs, that too for data-deficient (nutritionally) animals, is somewhat ambiguous or problematic. Through systematic meta-analyses, the present study formulated most up-to-date crayfish nutritional standards, against which a recyclable waste (biofloc biomass, BM) from intensive aquaculture systems was assessed as a novel protein source. Growth trajectory dependencies and thermal growth coefficient qualifying for good growth in crayfish (TGC 0.5-0.64 units) were benchmarked. Using these standards and a 7-week growth trial, BM's suitability as a novel protein source for red swamp crayfish Procambarus clarkii was evaluated through its graded inclusions in a commercial feed. Results suggest that BM can elevate growth at 33-66% inclusion in existing feed formulations. Beyond 66% inclusion, BM can deteriorate growth in crayfish due to high ash content (exceeding physiological limit > 14%), arginine deficiency (~ 14-20% lower than an optimum requirement), and insufficient non-protein energy: protein ratio (3.7 cal mg-1). Arginine is perhaps the most critical amino acid in dietary protein for crayfish, and deficient in BM. Although no critical bioaccumulation levels of heavy metals were breached by feeding 100% BM to crayfish, a mineral and heavy metal (Hg) stress seemed plausible. Crayfish raised solely on biofloc may not realize full growth potential.

6.
Environ Pollut ; 268(Pt B): 115781, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33049575

RESUMO

Freshwater ecosystems are negatively impacted by various pollutants, from agricultural, urban and industrial wastewater, with metals being one of the largest concerns. Moreover, freshwater ecosystems are often affected by alien species introductions that can modify habitats and trophic relationships. Accordingly, the threat posed by metals interacts with those by alien species, since the latter can accumulate and transfer these substances across the food web to higher trophic levels. How metals transfer within such communities is little studied. We analysed the concentration of 14 metals/metalloids (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Se, Zn, hereafter 'metal(s)') of eight fish and three crustacean species co-existing in the Arno River (Central Italy), most of which were alien. To assess the pathway of contaminants within the community, we coupled metal analysis with carbon and nitrogen stable isotope analysis derived from the same specimens. Crustaceans showed higher metal concentration than fish, except for Cd, Hg and Se that were higher in fish. We found evidence of trophic transfer for six metals (Cd, Cr, Hg, Mg, Se, Zn). Additionally, ontogenetic differences and differences among various fish tissues (muscle, liver, and gills) were found in metals concentration. Considerable biomagnification along the trophic chain was found for Hg, while other metals were found to biodilute. Using stable isotopes and Hg as a third diet tracer, we refined the estimations of consumed preys in the diet previously reconstructed with stable isotope mixing models. Alien species reach high biomass and can both survive to and accumulate high pollutants concentrations, potentially posing a risk for their predators and humans. A combined effect of environmental filtering and increased competition may potentially contribute to the disappearance of native species with lower tolerances.

7.
Integr Zool ; 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978865

RESUMO

The phylogeny of European crayfish fauna, especially with respect to Eastern European species, is still far from being completely resolved. To fill this gap, we analyzed most of the European crayfish species focusing on the phylogenetic position of the endemic crayfish Astacus colchicus, inhabiting Georgia. Three mitochondrial and one nuclear marker were used to study evolutionary relationships among European crayfish species, resulting in the unique phylogenetic position of A. colchicus indicating independent species status to A. astacus. Phylogenetic analyses revealed a deep molecular divergence of A. colchicus in comparison to A. astacus (6.5-10.9% in mtDNA and 1.1% in nDNA) as well as to Pontastacus leptodactylus and P. pachypus (5.5-10.0% in mtDNA and 1.4-2.4% in nDNA). Absent ventral process on second male pleopod and abdominal somites II and III with pleura rounded lacking prominent spines clearly indicate taxonomic assignment to the genus Astacus; however, the species is distributed almost in the middle of Ponto-Caspian area typical by occurrence of the genus Pontastacus. Several morphological indices linked to head length, carapace, and total body length and width were found to demonstrate apparent differences between A. colchicus and A. astacus. Although this study provides a novel insight into European crayfish phylogeography, we also point out the gaps in comprehensive study of the P. leptodactylus species complex, which could reveal details about the potential species status of particular species and subspecies within this genus.

8.
Sci Rep ; 10(1): 10119, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32572111

RESUMO

The direct effects of temperature increases and differences among life-history might affect the impacts of native and invasive predators on recipient communities. Comparisons of functional responses can improve our understanding of underlying processes involved in altering species interaction strengths and may predict the effect of species invading new communities. Therefore, we investigated the functional responses of the mourning gecko Lepidodactylus lugubris (Duméril & Bibron, 1836) to explore how temperature, body-size and prey density alter gecko predatory impacts in ecosystems. We quantified the functional responses of juvenile and adult geckos in single-predator experiments at 20, 23 and 26 °C. Both displayed saturating Type-II functional responses, but juvenile functional responses and the novel Functional Response Ratio were positively affected by temperature as juvenile attack rates (a) increased as a function of increased temperature. Handling times (h) tended to shorten at higher temperature for both predator stages. We demonstrate that the effects of temperature on functional responses of geckos differ across ontogeny, perhaps reflecting life-history stages prioritising growth and maturation or body maintenance. This indicates that temperature-dependent gecko predatory impacts will be mediated by population demographics. We advocate further comparisons of functional responses to understand the invasiveness and future predatory impacts of geckos, and other invasive species globally, as temperatures change.

9.
J Invertebr Pathol ; 173: 107390, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32353366

RESUMO

The crayfish plague pathogen Aphanomyces astaci, which is among the most studied pathogens of aquatic invertebrates, co-evolved with North American crayfish species but threatens crayfish on other continents. The pathogen causes mass mortalities, particularly in Europe. In this study we document 12 crayfish plague outbreaks that occurred from 2014 to 2019 in Czechia and, by using available molecular techniques (microsatellite and mtDNA markers), we reveal the A. astaci genotypes involved. Our results provide the first evidence of strains from genotype group D, originally associated with the host Procambarus clarkii, causing Astacus astacus and Austropotamobius torrentium mass mortalities in Czechia. Moreover, mtDNA sequencing confirmed two distinct haplotypes of the D haplogroup, indicating two independent sources of infection, presumably originating from ornamental crayfish in the pet trade or spreading from crayfish established in neighbouring countries. Genotype group A was recorded in two As. astacus mortalities, and genotype group E, associated with Faxonius limosus, in two Au. torrentium and three As. astacus mortalities. Microsatellite genotyping also reidentified the unusual genotype SSR-Up in two As. astacus outbreaks, ten years after its first documented occurrence. In addition, we tested healthy-appearing indigenous crayfish from 25 localities for potential chronic infections. No traces of A. astaci DNA were detected; chronic infections in European crayfish species thus do not seem a pervasive phenomenon in Czechia. However, their role as A. astaci latent reservoirs, especially in Pontastacus leptodactylus populations introduced to the country since the late 19th century, cannot be excluded.

10.
Chemosphere ; 257: 127189, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470540

RESUMO

The effects of chloridazon exposure at concentrations of 2.7 µg/L (maximal real environmental concentration in the Czech Republic), 27 µg/L, 135 µg/L and 270 µg/L on early life stages of marbled crayfish (Procambarus virginalis) were evaluated. Significantly higher glutathione S-transferase activity and reduced glutathione level was observed at all tested concentrations of chloridazon compared with the control. Chloridazon in concentrations 27, 135 and 270 µg/L caused delay ontogenetic development and slower growth. Histopathological changes in hepathopancreas were found in two highest tested concentrations (135 µg/L and 270 µg/L). Crayfish behaviour was not altered in control vs. exposed animals, while the activity parameters tend to decline with increasing chloridazon concentrations.


Assuntos
Astacoidea/fisiologia , Praguicidas/toxicidade , Piridazinas/toxicidade , Testes de Toxicidade , Animais , Astacoidea/efeitos dos fármacos , República Tcheca
11.
Sci Total Environ ; 711: 135138, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000346

RESUMO

Pharmaceutically active compounds (PhAC) have been increasingly detected in freshwater and marine waterbodies worldwide and are recognized as major emerging micropollutant threat to the aquatic environment. Despite their low concentrations in the environment, there is evidence of effects on non-target aquatic organisms in natural habitats. To assess the potential effects of PhACs on its burrowing behavior, we exposed the red swamp crayfish Procambarus clarkii to methamphetamine or tramadol at the environmentally relevant concentration of 1 µg/L. Methamphetamine-exposed females constructed burrows of lower depth and volume relative to individual weight than did controls. Tramadol-exposed females consistently exhibited a tendency for smaller burrows, but this difference was not significant. Exposed males showed a non-significant tendency to excavate larger burrows compared with the control. Control and tramadol-treated females maintained the natural tendency of constructing relatively deeper and/or larger-volume burrows compared with males. This sex-related pattern was not detected in the methamphetamine group. The rate of human therapeutic PhAC usage is relatively stable year-round, and impacts on crayfish burrowing can be particularly damaging during periods of drought, when the dilution of waste waters is reduced, and burrowing becomes a critical survival strategy. Our results suggest that an increasingly broad range of environmental impacts of PhACs on non-target organisms can be expected in natural ecosystems.


Assuntos
Astacoidea , Ecossistema , Animais , Organismos Aquáticos , Meio Ambiente , Água Doce , Humanos
12.
Sci Rep ; 10(1): 875, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964976

RESUMO

The effects of the herbicide metazachlor and its major metabolite metazachlor OA at two concentrations, including environmentally relevant concentrations of metazachlor (0.0115 µmol/l and 0.0790 µmol/l) and metazachlor OA (0.0117 µmol/l and 0.0805 µmol/l), respectively, were evaluated on early ontogeny, growth, behaviour, oxidative stress, antioxidant enzyme levels, histology, and mortality of marbled crayfish Procambarus virginalis. Both tested concentrations of metazachlor and metazachlor OA were associated with significantly lower growth and delayed ontogenetic development compared to controls. Exposure of metazachlor at 0.0115 µmol/l and metazachlor OA at 0.0117 µmol/l and 0.0805 µmol/l resulted in significantly lower activity of total superoxide dismutase (SOD), catalase (CAT), glutathione s-transferase (GST), glutathione reductase (GR), and reduced glutathione (GSH) compared with control and resulted in gill anomalies ranging from wall thinning to focal disintegration of branchial structure. Metazachlor at the environmentally relevant concentration of 0.0790 µmol/l was associated with significant alterations of crayfish distance moved and walking speed. The potential risk associated with metazachlor use in agriculture related to effects on non-target aquatic organisms.

13.
J Fish Dis ; 43(1): 129-138, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724193

RESUMO

The crayfish plague pathogen (Aphanomyces astaci) can be transmitted through the digestive system of fish, but its dispersal through mammalian and bird digestive tracts has been considered unlikely, and direct experimental evidence remains scarce. We present a small-scale transmission experiment with European otter and American mink fed with infected crayfish, and experiments testing survival of cultures of five A. astaci strains at temperatures corresponding to those inside mammal and bird bodies. The pathogen was neither isolated from predator excrements nor transmitted to susceptible crayfish exposed to excrements. In agar-based artificial media, it occasionally survived for 15 min at 40.5°C and for 45 min at 37.5°C, but not so when incubated at those temperatures for 45 min and 75 min, respectively. The five tested strains differed in resistance to high temperatures, two (of genotype groups E and D) being more susceptible than other three (of groups A, B and D). Their survival to some extent varied when exposed to the same temperature after several weeks or months, suggesting that some yet-unknown factors may influence A. astaci resistance to temperature stress. Overall, we support the notion that passage through the digestive tract of warm-blooded predators makes A. astaci transmission unlikely.


Assuntos
Aphanomyces/fisiologia , Fenômenos Fisiológicos do Sistema Digestório , Infecções/transmissão , Vison , Lontras , Animais , Fezes , Temperatura
14.
Aquat Toxicol ; 213: 105222, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31212248

RESUMO

Pharmaceutically active compounds are major contaminants of aquatic environments that show direct and indirect effects on aquatic organisms even at low concentrations. The aim of this study was to assess the effects of the illicit drug methamphetamine and the antidepressant sertraline on clonal marbled crayfish Procambarus virginalis. Crayfish exposed to the environmentally relevant concentrations of methamphetamine of ∼1 µg L-1 did not exhibit significant differences from unexposed controls in distance moved, velocity, and activity level with or without available shelter. Sertraline-exposed (∼1 µg L-1) crayfish were significantly more active, regardless of available shelter, and moved greater distances when shelter was available, compared to control crayfish. Crayfish exposed to methamphetamine and sertraline spent significantly more time outside the shelters compared to controls. Sertraline-exposed crayfish spawned more frequently and showed higher mortality than controls. The results suggest that the low environmental concentrations of the tested compounds could alter the behavior and life history traits of crayfish, resulting in higher reproductive effort and mortality.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/crescimento & desenvolvimento , Astacoidea/efeitos dos fármacos , Astacoidea/crescimento & desenvolvimento , Comportamento Animal/efeitos dos fármacos , Estágios do Ciclo de Vida/efeitos dos fármacos , Metanfetamina/toxicidade , Sertralina/toxicidade , Animais , Invertebrados , Poluentes Químicos da Água/toxicidade
15.
Chemosphere ; 224: 616-625, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30849622

RESUMO

Increasing production of energy crops in Europe, mainly maize and rapeseed, has altered patterns of pesticide use in recent decades. The long-term effects of S-metolachlor (S-M) and of its metabolite metolachlor OA (M-OA) at the environmentally relevant concentration of 4.2 µg L-1 and at 42 µg L-1 (ten-fold concentration) on marbled crayfish (Procambarus virginalis) were evaluated in a 28-day exposure and after a subsequent 28-day recovery period. Indicators assessed were behaviour; biochemical haemolymph profile; oxidative and antioxidant parameters of gill, hepatopancreas, and muscle; and histology of hepatopancreas and gill. Results showed biochemical haemolymph profile (lactate, alanine aminotransferase, aspartate aminotransferase, inorganic phosphate), lipid peroxidation in hepatopancreas, and antioxidant parameters (catalase, reduced glutathione, glutathione S-transferase) of hepatopancreas and gill of crayfish exposed to S-M and M-OA to significantly differ from controls (P < 0.01). Antioxidant biomarker levels remained different from controls after a 28-day recovery period. Differences in behaviour including speed of movement and velocity, and histopathological damage to gill and hepatopancreas were associated with S-M and M-OA exposure and persisted after 28 days in S-M- and M-OA-free water. Results suggest harmful effects of low concentrations of S-M and its metabolite M-OA on non-target organisms and provide information for assessing their effects at environmentally relevant concentrations.


Assuntos
Acetamidas/farmacologia , Astacoidea/efeitos dos fármacos , Acetamidas/química , Acetamidas/metabolismo , Animais , Antioxidantes/metabolismo , Comportamento Animal/efeitos dos fármacos , Europa (Continente) , Hemolinfa/metabolismo , Hepatopâncreas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos
16.
Sci Total Environ ; 665: 718-723, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30780017

RESUMO

Calypso 480 SC (CAL) is an insecticide containing the active substance thiacloprid (480g/L) belonging to the family of neonicotinoids. Crayfish represent an important component of aquatic ecosystems and are considered sensitive indicators of water pollution. The aim of this study was to investigate the effects of acute exposure of CAL on common yabby crayfish (Cherax destructor) at concentrations of 0.1, 0.5, 1, 5, 10, 25, and 50mg/L. Crayfish behavior and mortality were monitored daily, and the lethal concentrations (LC0, LC50, LC100) of CAL were evaluated at 24h, 48h, 72h, and 96h. Three concentrations of CAL (0.1, 1, 10mg/L) were selected for assessment of oxidative stress (lipid peroxidation) and antioxidant parameters superoxide dismutase, catalase, glutathione S-transferase and reduced glutathione in crayfish hepatopancreas, muscle, and gill tissue at the conclusion of the acute test. Differences in behavior of exposed crayfish from controls were observed at concentration≥5mg/L of CAL. The 96h LC50 value for the common yabby was 7.7mg/L for Calypso 480 SC. The acute exposure showed reduction of the level lipid peroxidation in hepatopancreas in all experimental groups compared with control. The results of antioxidant activity showed a significant change on glutathione S-transferase in tissue of hepatopancreas while no differences were observed on the others antioxidant parameters in crayfish's tissues. The study provides valuable information on effects of neonicotinoid insecticides on a non-target organism, the crayfish, an indicator of pollution and an important element of stable aquatic ecosystems.


Assuntos
Astacoidea/efeitos dos fármacos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Tiazinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Testes de Toxicidade Aguda
17.
Pestic Biochem Physiol ; 153: 87-94, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30744900

RESUMO

The effects of s-metolachlor chronic exposure at concentrations of 1.1 µg/L (maximal real environmental concentration in the Czech Republic), 11 µg/L (environmental relevant concentration) and 110 µg/L on early life stages of marbled crayfish (Procambarus virginalis) was evaluated under laboratory conditions. All s-metolachlor exposures resulted in higher mortality, delay ontogenetic development with accompanied slower growth and excited behaviour (increase of total distance moved and walking speed). Significantly lower superoxide dismutase, catalase, glutathione S-transferase activity and reduced glutathione level was observed at two higher tested concentrations (11 and 110 µg/L) of s-metolachlor compared with the control. S-metolachlor in concentrations 110 µg/L showed alteration of the tubular system of hepatopancreas including focal disintegration of tubular epithelium and notable reduction in epithelial cells number, especially B-cells. In conclusion, potential risk associated with using of s-metolachlor in agriculture, due to effects on non-target aquatic organisms as documented on early life stages of marbled crayfish in this study, should be taken into account.


Assuntos
Acetamidas/toxicidade , Astacoidea/efeitos dos fármacos , Herbicidas/toxicidade , Animais , Astacoidea/fisiologia , Comportamento Animal/efeitos dos fármacos , Feminino , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia
18.
Sci Total Environ ; 643: 1456-1463, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189562

RESUMO

The metolachlor OA is a metabolite of herbicide metolachlor and s-metolachlor. The objective of the present study was to assess the effect metolachlor OA on early life stages of marbled crayfish (Procambarus virginalis). The early life stages of marbled crayfish were exposed for 45 days to three concentrations of metolachlor OA: 4.2 µg/L (environmentally relevant concentration, E1), 42 µg/L (E2) and 420 µg/L (E3) under laboratory conditions. The effects were assessed on the basis of mortality, growth, ontogenetic development, behaviour, oxidative stress, antioxidant biomarkers and histopathology. Metolachlor OA caused significantly lower growth, superoxide dismutase, catalase and glutathione s-transferase activity in all tested concentrations. Metolachlor OA in higher concentrations (42 and 420 µg/L) resulted in significantly delayed ontogenetic development, lower reduced glutathione level and lipid peroxidation. Metolachlor OA has not significant effect on behaviour (activity, total distance moved and walking speed). Histological examination revealed alteration of hepatopancreas and gills in crayfish exposed to two higher tested concentrations. Hepatopancreas reflected histomorphological structural changes of individual cell types. Changes of gills included focal hemocytic infiltration together with enlargement of intralamellar space packed with granular substance. In conclusion, chronic metolachlor OA exposure affected growth, ontogenetic development, and the antioxidant system and caused pathological changes in hepatopancreas and gills of early life stages of marbled crayfish.


Assuntos
Acetamidas/toxicidade , Astacoidea/fisiologia , Herbicidas/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Catalase/metabolismo , Brânquias , Estresse Oxidativo , Superóxido Dismutase/metabolismo
19.
Chem Biol Interact ; 291: 95-102, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29908168

RESUMO

Atrazine (ATR) is a triazine herbicide banned in the European Union. It remains one of the most widely used herbicides in other parts of the world. Considering the scarcity of data on its possible harm to the environment and to human health, we assessed sub-chronic effects of a 14-day exposure at the environmentally relevant concentration of 6.86 µg/L and at 10% of the 96hLC50 (1.21 mg/L) in crayfish Cherax destructor and their recovery in a 14-day period in ATR-free water. Indicators assessed were behavior; hemolymph biochemical profile; oxidative and antioxidant parameters in gill, hepatopancreas, and muscle; and histology of gill and hepatopancreas. Crayfish exposed to the environmental concentration showed significant differences (P < 0.01) from controls in biochemical parameters of hemolymph (lactate, alkaline phosphatase) and activity of superoxide dismutase, as well as in histology of gill tissue. The higher concentration led to low motor activity, differences in biochemical profile of hemolymph (lactate, alkaline phosphatase, ammonia, glucose), antioxidant biomarkers (superoxide dismutase, catalase, glutathione reductase, glutathione S-transferase, reduced glutathione), as well as gill and hepatopancreas histology. Some observed effects persisted after 14-days recovery in ATR-free water. The results provide evidence that environmental concentrations of ATR produce negative effects on freshwater crayfish.


Assuntos
Astacoidea/citologia , Astacoidea/metabolismo , Atrazina/toxicidade , Exposição Ambiental , Testes de Toxicidade Crônica , Animais , Antioxidantes/metabolismo , Astacoidea/efeitos dos fármacos , Biomarcadores/metabolismo , Brânquias/citologia , Brânquias/efeitos dos fármacos , Glutationa Transferase/metabolismo , Hemolinfa/efeitos dos fármacos , Hemolinfa/metabolismo , Hepatopâncreas/citologia , Hepatopâncreas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo
20.
Ecol Evol ; 8(9): 4455-4464, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29760887

RESUMO

Biogeographical barriers formed by natural forces over billions of years have been substantially disrupted by human activity, particularly in recent centuries. In response to these anthropogenic changes, global homogenization of biota is observed at an ever-increasing rate, causing environmental and economic losses as well as emerging health risks. Identifying factors underlying alien species richness is essential for prevention of future introductions and subsequent spread. In this study, we examined the effects of environmental and human-related factors on distribution of alien animal species richness in the Czech Republic (Central Europe). We compiled a set of maps showing the level of invasion of six categories of alien animal species in each of 628 grid cells (ca. 12.0 × 11.1 km) covering the Czech Republic. Relationships between alien species richness and 12 variables characterizing climatic conditions, topography, land cover, and human population size were calculated using the generalized least squares method. Species richness of all alien species, of invertebrates, and of terrestrial species showed the strongest positive relationship with mean annual temperature, while the number of black and grey (proposed prominent invaders) and aquatic species was most closely related to the presence of large rivers. Alien vertebrates showed a strong negative relationship with annual precipitation. The highest alien animal species richness was found in and near large population centers and in agricultural landscapes in warm and dry lowlands. The gateways for alien aquatic species are rather large rivers over sport fishing and aquaculture import. Compiled maps create a powerful visual communication tool, useful in development of programs to prevent future introductions.

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