Functional diversity of staphylinid beetles (Coleoptera: Staphylinidae) in maize fields: testing the possible effect of genetically modified, insect resistant maize.

Staphylinid beetles are recommended bioindicators for the pre-market environmental risk assessment of genetically modified (GM) insect protected maize expressing the Cry3Bb1 toxin. Our multiannual study is a unique European analysis of a staphylinid community within a 14 ha maize field. GM maize, its near-isogenic hybrid (with or without insecticide treatment), and two other reference hybrids were each grown in five 0.5 ha plots. The opportunity for exposure to Cry toxin from plant residues ploughed into the soil was shown by the presence of saprophagous dipteran larvae that are common prey of predatory staphylinid species and hosts of the parasitoid species. 2587 individuals belonging to 77 staphylinid species were sampled using pitfall traps. Lesteva longoelytrata (31%), Oxypoda acuminata (12%), Aloconota sulcifrons (8%) and Anotylus rugosus (7%) were the most abundant beetles in the field. Bionomics, food specialization, temperature requirements and size group were assigned for 25 most common species. These traits determine the occurrence of staphylinid beetles in the field, the food sources they could utilize and thus also their likely contact with the Cry3Bb1 toxin. Statistical analysis of activity abundance, Rao indices and multivariate analysis of distribution of particular categories of functional traits in the field showed negligible effects of the experimental treatments, including the GM maize, upon the staphylinid community. Staphylinid beetles represent a considerably diverse part of epigeic field fauna with wide food specialization; these features render them suitable for the assessment of environmental safety of GM insect protected maize. However, the availability of prey and the presence of particular staphylinid species and their abundance are highly variable; this complicates the interpretation of the results.

Splenic lipidosis in intensively cultured perch, Perca fluviatilis L.

Macroscopically visible lipid deposition varying in size from pinpoint to 8-mm diameter was found in spleens of a population of intensively farmed perch, Perca fluviatilis L. over a 24-month rearing period. Large agglomerates of adipocytes distinguishable from surrounding normal tissue occurred in all individuals with spleen lipidosis. Several affected fish presented total dystrophy of large clusters of hepatocytes. Prevalence of lipidosis was 5.0% at 12 months and 16.6% at 24 months. There was no significant difference between fatty acid profiles of liver or perivisceral fat of perch with and without lipidosis except for linoleic, myristic, γ-linoleic, cis-eicosatrienic, palmitooleic acid. Body weight and hepatosomatic, perivisceral fat and splenosomatic indices were not associated with lipidosis. There was no significant effect of lipidosis on mortality or growth.

Factors Affecting Antioxidant Response in Fish from a Long-term Mercury-Contaminated Reservoir.

The objective of this work was to evaluate antioxidant defence and oxidative damage in organs (liver, gills, kidney, and brain) of five fish species (Aspius aspius, Esox lucius, Sander lucioperca, Abramis brama, Rutilus rutilus) from the long-term mercury-contaminated Skalka Reservoir in the Czech Republic. Special emphasis was placed on a comprehensive assessment of the factors that may affect the antioxidant response to mercury in fish. Antioxidant enzymes (glutathione reductase, glutathione peroxidase, and glutathione-S-transferase) did not significantly respond to mercury contamination. Levels of the analysed enzymes and oxidative damage to lipids were predominantly determined by a separate organ factor or species factor, or by the combination of both (p < 0.001). Levels of total glutathione and the reduced/oxidized glutathione ratio were influenced by mercury contamination in combination with their specific organ distribution (p < 0.001). Our results suggest that species and type of organ alone or in combination are more important factors than chronic exposure to mercury contamination with respect to effects on antioxidant defence in fish under field conditions. Our findings suggest that the main antioxidant defensive mechanism in fish from the studied long-term mercury contaminated site was the inter-tissue distribution of glutathione.

The toxicity and adverse effects of selected drugs in animals--overview.

Therapeutic products quite often are causes of poisoning in both small and large animals. Drug poisonings in animals occur commonly due to off-label use of medicines, wrong dosage, negligence, accidental ingestion and deliberate poisonings. Toxicity of veterinary drugs may become evident also in therapeutic doses when adverse effects may occur. The aim of this review is to inform veterinary specialists about both veterinary and human drugs, specifically antiparasitics, non-steroidal anti-inflammatory drugs and other medicinal substances, which are most often reported to cause acute poisonings or adverse reactions in animals and to contribute to. their broader knowledge and more accurate use of medicines, improving instructions to the animal owners and, hopefully, decrease the incidence of drug poisonings in animals.

Alkylphenol ethoxylates and alkylphenols--update information on occurrence, fate and toxicity in aquatic environment.

Alkylphenols and their precursors, alkylphenol etoxylates, are a group of manmade chemicals used mainly as surfactants in domestic and industrial applications worldwide. It has been well established that they have endocrine disruption activity, hepatotoxic, genotoxic and other negative effects on animal and human health. In spite of the effort to reduce their use, they persist in the environment not only in industrial but also in remote regions, and were detected in the variety of natural matrices including air, water, soil as well as food products, and human blood and urine worldwide. This article summarizes their occurrence, fate in natural conditions, and toxicity including mode of action. A subject of our concern was the aquatic environment as the most important reservoir and target of their deleterious impact.

Recovery ability of common carp (Cyprinus carpio) after a short-term exposure to terbuthylazine.

Effects of a high terbuthylazine concentration (3.3 mg/1) on Cyprinus carpio were studied using a commercial herbicide formulation Click 500 SC (terbuthylazine 500 g/l). The fish were exposed to the pesticide for 24 h and allowed to recover for 6 days. Biometric parameters, plasma biochemical parameters and biomarkers of oxidative stress as well as histopathological changes in selected tissues were assessed on day 1 and 7. After a 24-h exposure, there were significant alterations found in the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as well as in the plasma concentrations of glucose, natrium, chlorides, calcium and phosphorus. Hepatosomatic index, plasma albumin and lactate reflected the treatment with a delay. Ion levels and ALT were found to be restored after a 6-day recovery period, which was too short for AST activity and glucose to diminish to the control levels. The histopathological examination revealed disorders in the gills of the exposed fish, however, the changes were not detected after a 6-day recovery period. The study shows high regeneration potential of the fish.

Polystyrene microparticles can affect the health status of freshwater fish - Threat of oral microplastics intake.

Plastic waste pollution is considered one of the biggest problems facing our planet. The production and use of these materials has led to huge amounts of plastic waste entering the aquatic environment and affecting aquatic life. In our experiment, the effect of polystyrene microparticles (PS-MPs; 52.5 ± 11.5 µm) on individual juvenile rainbow trout (Oncorhynchus mykiss) was tested at three different dietary concentrations of 0.5, 2 and 5 % for six weeks. At the end of the experiment, various health parameters of exposed organisms were compared with the control group. The haematological profile revealed an immune response by a decrease in lymphocyte count with a concurrent increase in the number of neutrophil segments at the highest concentration of PS-MPs (5 %). Biochemical analysis showed significant reductions in plasma ammonia in all tested groups, which may be related to liver and gill damage, as determined by histopathological examination and analysis of inflammatory cytokines expression. In addition, liver damage can also cause a significant decrease in the plasma protein ceruloplasmin, which is synthesized in the liver. PS-MPs disrupted the antioxidant balance in the caudal kidney, gill and liver, with significant changes observed only at the highest concentration. In summary, PS-MPs negatively affect the health status of freshwater fish and represent a huge burden on aquatic ecosystems.

Effects of long-term exposure to simazine in real concentrations on common carp (Cyprinus carpio L.).

The effects of a 90 day simazine exposure at concentrations of 0.06 (reported concentration in Czech rivers), 1, 2, and 4 µg L⁻¹ were assessed in one-year-old common carp (Cyprinus carpio L.). Its influence on biometric parameters, hematology, blood biochemistry, liver biomarkers, and histology was investigated. Biometric parameters of common carp exposed to simazine at 0.06 µg L⁻¹ showed no differences from untreated fish. Simazine concentrations of 1, 2, and 4 µg L⁻¹ caused significant (p<0.01) increase of hepatosomatic indices relative to controls. Hematological profiles showed significant (p<0.01) decrease in leukocyte count relative to controls at all concentrations. Biochemical profiles of common carp exposed to simazine at all concentrations showed significant (p<0.01) increase in activity of alkaline phosphatase. In addition, at concentrations of 1 and 2 µg L⁻¹, there was a significant increase in alanine aminotransferase (p<0.05), and, at 4 µg L⁻¹, a significant increase in total protein (p<0.05), albumins (p<0.05), and alanine aminotransferase (p<0.05) compared with controls. Renal histology revealed severe hyaline degeneration of the epithelial cells of caudal kidney tubules in fish at all exposure levels compared to controls. Chronic exposure of common carp to simazine caused significant shifts in hematological, biochemical, and biometric profiles, and histopathological changes. The results of this study indicate that chronic exposure of simazine has altered multiple physiological indices in fish hematology and biochemistry, which potentially may be a biomarker of simazine toxicity; however, before these parameters are used as special biomarkers for monitoring residual simazine in aquatic environment, more detailed experiments in laboratory need to be performed in the future.

Effects of subchronic exposure to atrazine on zebrafish (Danio rerio).

The aim of this study was to investigate the effects of subchronic exposure to atrazine on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) in Danio rerio. Juvenile growth tests were performed on D. rerio according to OECD method No. 215. For 28 days, fish at an initial age of 30 days were exposed to the environmental atrazine concentration commonly detected in Czech rivers (0.3 microg/L) and a range of sublethal concentrations of atrazine (3.0, 30.0 and 90.0 microg/L). The results showed decreasing growth rates and morphological changes in the liver (dystrophic lesions of hepatocytes) at 90.0 microg/L of atrazine. The environmental concentration of atrazine in Czech rivers did not have any effect on fish growth and development of histopathological changes in D. rerio. The value of NOEC was 30.0 microg/L and the value of LOEC was 90.0 microg/L.

Effects of plastic particles on aquatic invertebrates and fish - A review.

This review summarises the current knowledge on the effects of microplastics and their additives on organisms living in the aquatic environment, particularly invertebrates and fish. To date, microplastics have been recognised to affect not only the behaviour of aquatic animals but also their proper development, causing variations in fertility, oxidative stress, inflammations and immunotoxicity, neurotoxicity, and changes in metabolic pathways and gene expression. The ability of microplastics to bind other xenobiotics and cause combined toxicity along side the effect of other agents is also discussed as well. Microplastics are highly recalcitrant materials in both freshwater and marine environments and should be considered extremely toxic to aquatic ecosystems. They are severely problematic from ecological, economic and toxicological standpoints.

Non-steroidal anti-inflammatory drugs caused an outbreak of inflammation and oxidative stress with changes in the gut microbiota in rainbow trout (Oncorhynchus mykiss).

One of the main contributors to pharmaceutical pollution of surface waters are non-steroidal anti-inflammatory drugs (NSAIDs) that contaminate the food chain and affect non-target water species. As there are not many studies focusing on toxic effects of NSAIDs on freshwater fish species and specially effects after dietary exposure, we selected rainbow trout (Oncorhynchus mykiss) as the ideal model to examine the impact of two NSAIDs - diclofenac (DCF) and ibuprofen (IBP). The aim of our study was to test toxicity of environmentally relevant concentrations of these drugs together with exposure doses of 100× higher, including their mixture; and to deepen knowledge about the mechanism of toxicity of these drugs. This study revealed kidneys as the most affected organ with hyalinosis, an increase in oxidative stress markers, and changes in gene expression of heat shock protein 70 to be signs of renal toxicity. Furthermore, hepatotoxicity was confirmed by histopathological analysis (i.e. dystrophy, congestion, and inflammatory cell increase), change in biochemical markers, increase in heat shock protein 70 mRNA, and by oxidative stress analysis. The gills were locally deformed and showed signs of inflammatory processes and necrotic areas. Given the increase in oxidative stress markers and heat shock protein 70 mRNA, severe impairment of oxygen transport may be one of the toxic pathways of NSAIDs. Regarding the microbiota, an overgrowth of Gram-positive species was detected; in particular, significant dysbiosis in the Fusobacteria/Firmicutes ratio was observed. In conclusion, the changes observed after dietary exposure to NSAIDs can influence the organism homeostasis, induce ROS production, potentiate inflammations, and cause gut dysbiosis. Even the environmentally relevant concentration of NSAIDs pose a risk to the aquatic ecosystem as it changed O. mykiss health parameters and we assume that the toxicity of NSAIDs manifests itself at the level of mitochondria and proteins.

Assessment of diclofenac LC50 reference values in juvenile and embryonic stages of the zebrafish (Danio rerio).

The aim of the study was to compare the acute toxicity of diclofenac to juvenile and embryonic stages of the zebrafish (Danio rerio). Acute toxicity tests were performed on the aquarium fish Danio rerio, which is one of the model organisms most commonly used in toxicity testing. The tests were performed using a semi-static method according to OECD guideline No. 203 (Fish, acute toxicity test). Embryo toxicity tests were performed in zebrafish embryos (Danio rerio) in compliance with OECD No. 212 methodology (Fish, short-term toxicity test on embryo and sac-fry stages). The results were subjected to a probit analysis using the EKO-TOX 5.2 programme to determine 96hLC50 and 144hLC50 (median lethal concentration, 50% mortality after a 96 h or 144 h interval, respectively) values of diclofenac. The statistical significance of the difference between LC50 values in juvenile and embryonic stages of Danio rerio was tested using the Mann-Whitney non-parametric test implemented in the Unistat 5.1 programme. The LC50 mean value of diclofenac was 166.6 +/- 9.8 mg/L in juvenile Danio rerio, and 6.11 +/- 2.48 mg/L in embryonic stages of Danio rerio. The study demonstrated a statistically higher sensitivity to diclofenac (P < 0.05) in embryonic stages compared to the juvenile fish.

Do foodborne polyethylene microparticles affect the health of rainbow trout (Oncorhynchus mykiss)?

Due to the fact that plastic pollution is a global environmental problem of modern age, studies on the impact of these synthetic materials on aquatic, and especially fish organisms, are an important part of the ecosystem and human nutrition. In our study, the toxicity of pristine polyethylene (PE) microparticles (approx. 50 µm) on rainbow trout (Oncorhynchus mykiss) was tested in three different dietary concentrations - 0.5%, 2% and 5%. After six weeks of exposure, various health indices were evaluated. Electron microscopy of the intestine revealed the disintegration of PE particles to <5 µm in size, and thus we concluded that microplastics are able to reach tissues. The haematological profile revealed changes in total red blood cells count and haematocrit (5% PE) which could be associated with spleen congestion observed histologically. The marker of lipid peroxidation was increased in gills suggesting the disruption of balance in antioxidant enzymes capacity and histopathological imaging revealed inflammation in higher PE concentrations. In addition, ammonia was decreased and calcium elevated in biochemical profile, confirming the gill damage. Electron microscopy of the gills showed lesions of lamellae and visible rings around the mucinous cell opening indicating their higher activity. Another injured was the liver tissue, as confirmed by hepatodystrophies and increased expression of pro-inflammatory genes in 2% PE. Impaired innate immunity was confirmed by an increased presence of mucinous cells and a decrease in leukocytes. Kidney damage manifested itself by higher expression of pro-inflammatory cytokines and histopathology. The damage in gills, liver and kidney together correlated with the increased antioxidant capacity of plasma. In conclusion, PE microparticles are able to affect health indices of O. mykiss. The potential problem for aquatic ecosystems and even human consumption should be considered.

Effects of sub-chronic exposure to terbutryn in common carp (Cyprinus carpio L.).

The sub-chronic effects of terbutryn at concentrations 0.02 (reported concentration in Czech rivers), 4, 20, and 40 microg L(-1) were assessed in one-year-old common carp (Cyprinus carpio L.) exposed for 28 days and compared to a non-treated control group. Its influence on biometric parameters, hematology, blood biochemistry, and histology was investigated. Exposure to terbutryn at 0.02 microg L(-1) showed no observable effect, whereas exposure to 4, 20, and 40 microg L(-1) showed significantly higher erythrocyte counts, ammonia levels, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and lactate, but significantly lower mean corpuscular volume, mean corpuscular hemoglobin, and creatine. Cell shape changes and lipid inclusions were found in hepatocytes, and there was destruction of caudal kidney tubules when compared to control fish.

High resolution mass spectrometry analysis of the sertraline residues contained in the tissues of rainbow trout reared in model experimental conditions.

The growing consumption of pharmaceuticals in the human population and the insufficient efficiency of their elimination in waste water has a long-term negative impact on the environment of aquatic ecosystems, including the organisms that inhabit them. A significant contributor is the consumption of anti-depressants from the SSRI group, which corresponds to their increasing concentration in the environment. The aim of this work was to determine if antidepressant sertraline is able to be stored in fish organisms and to evaluate the content of residues in various body tissues. Rainbow trout (Oncorhynchuss mykkis) was selected as the test organism and was artificially exposed to the antidepressant for 1 month (concentrations 0; 4.2; 44 and 400 ng.g-1 sertraline in the feed). Liver, kidney, brain and muscle tissue biopsies samples were taken for analysis. Detection was performed using an Accela 1250 LC pump and an Accela autosampler coupled with a high-performance mass analyzer with a heated electrospray ionization source Q-Exactive Orbitrap, operating in positive ionization mode and in PRM mode (m/z 306.08108->275.03888 and 309.009991->275.03888 for sertraline and internal standard, respectively). The limit of quantification of the method was 0.1 ng.g-1 of sertraline and the calibration curve showed a good linearity up to 20 ng.g-1. From the collected data, amount of residues was found in the liver, kidney and brain. In contrast, the incidence of residues in muscle tissue was not detected in all groups, which is favorable from the point of view of fish meat consumption, by humans.

Could the musk compound tonalide affect physiological functions and act as an endocrine disruptor in rainbow trout?

In the present study, the effect of polycyclic musk compound tonalide (AHTN) in two concentrations was studied in male rainbow trout (Oncorhynchus mykiss, Walbaum 1792). A feeding trial was conducted with AHTN incorporated into feed granules. One concentration was environmentally relevant (854 µg/kg); the second one was 10× higher (8699 µg/kg). The fish were fed twice a day with the amount of feed at 1 % of their body weight. After an acclimatization period, the experimental phase in duration of six weeks followed. At the end of the experiment, fish were sampled and the biometrical data were recorded. Subsequently, hematological and biochemical tests, histopathological examination, analysis of oxidative stress markers and evaluation of endocrine disruption using plasma vitellogenin were performed. In conclusion, an increase of hematocrit for both AHTN concentrations was found, but no significant changes were observed in biochemical profile. Moreover, AHTN caused lipid peroxidation in caudal kidney tissue, which was confirmed by histopathological images. The long-lasting AHTN exposure could thus be harmful for maintaining homeostasis in the rainbow trout organism. However, the vitellogenin concentration seemed not to be affected by AHTN.

Effects of pollution on chub in the River Elbe, Czech Republic.

The Elbe River is one of the most polluted aquatic ecosystems in the Czech Republic. The effect of three major chemical plants located on the Elbe River (at Pardubice, Neratovice, and Usti nad Labem) on fish was studied in 2004. Health status, chemical concentrations (Hg, PCB, DDT, HCH, HCB, OCS, 4-tert-nonylphenols, 4-tert-octylphenol) in muscle, and biomarkers (hepatic ethoxyresorufin-O-deethylase (EROD), plasma vitellogenin, and plasma 11-ketotestosterone) were assessed in male chub (Leuciscus cephalus L.). Differences between localities upstream (US) and downstream (DS) from the monitored source of pollution were identified. Fish from DS sampling sites showed significantly higher levels of contaminants than fish from US sampling sites. Generally, the concentrations of pollutants in fish from the Elbe sites were significantly higher compared to the reference site. Reduced gonad size, decreased plasma levels of 11-ketotestosterone, EROD and vitellogenin induction, and histopathologies of male gonads indicated harmful effects of aquatic pollution in fish from the Czech portion of the Elbe River.

Effects of bifenthrin on some haematological, biochemical and histopathological parameters of common carp (Cyprinus carpio L.).

The aim of this study was to assess the effect of bifenthrin on common carp (Cyprinus carpio L.). The 96-h LC50 value of Talstar EC 10 (active substance 100 g l(-1) bifenthrin) was found to be 57.5 microg l(-1). Examination of haematological and biochemical profiles and histological tissue examination was performed on common carp after 96 h of exposure to Talstar EC 10 (57.5 microg l(-1)). The experimental group showed significantly higher (P < 0.01) values of plasma glucose, ammonia, aspartate aminotransferase and creatine kinase as well as the relative and absolute monocyte count, compared with the control group. Histological examination revealed teleangioectasiae of secondary gill lamellae and degeneration of hepatocytes. The bifenthrin-based Talstar EC 10 pesticide preparation was classified as a substance strongly toxic for fish.

Sex differentiation and vitellogenin and 11-ketotestosterone levels in chub, Leuciscus cephalus L., exposed to 17 beta-estradiol and testosterone during early development.

The effects of 17 beta-estradiol (E(2)) and testosterone (T) singly and in combination were tested on juvenile chub (Leuciscus cephalus L.). Vitellogenin (VTG) and 11-ketotestosterone (11-KT) were determined by ELISA in whole body homogenates and the gonads were examined histologically. Testosterone and estradiol, in combination, significantly increased whole body VTG (p < 0.01), but not 11-KT, compared to controls and the T treated groups. The only intersex observed (1/80) was in the combined treatment group. We suggest that VTG measured in whole body homogenates could be used to determine the effects of exogenous steroids in juvenile chub.

Effects of acute exposure to metribuzin on some hematological, biochemical and histopathological parameters of common carp (Cyprinus carpio L.).

The aim of the study was to evaluate acute toxic effects of the preparation Sencor 70 WG (metribuzin 70% W/V) on hematological, biochemical indices and histology of the common carp (Cyprinus carpio L.). In carp exposed for 96 h to Sencor 70 WG in the concentration of 250.2 mg/L, showed significantly lower (p<0.01) values of plasma total proteins, albumins, total globulins, triacylglycerols, lactate dehydrogenase, lactate, inorganic phosphate, hematocrit, hemoglobin concentration, mean erythrocyte volume, the leucocrite value, lymphocyte, and significantly higher (p<0.01) values of glucose, ammonia, calcium, monocytes, neutrophile granulocytes, developmental forms myeloid sequence and basophiles compared to the control group. Histopathological examination revealed hyaline degeneration of the epithelial cells of renal tubules of the caudal kidney. This alteration of kidney resulted in hypoproteinemia, followed by generation of transudate in body cavity.