Long-term dietary exposure to the non-steroidal anti-inflammatory drugs diclofenac and ibuprofen can affect the physiology of common carp (Cyprinus carpio) on multiple levels, even at "environmentally relevant" concentrations

The aim of the study was to evaluate the effects of emerging environmental contaminants, the non-steroidal anti-inflammatory drugs (NSAIDs) diclofenac (DCF) and ibuprofen (IBP), on physiological functions in juvenile common carp (Cyprinus carpio). Fish were exposed for 6 weeks, and for the first time, NSAIDs were administered through diet. Either substance was tested at two concentrations, 20 or 2000 μg/kg, resulting in four different treatments (DCF 20, DCF 2000, IBP 20, IBP 2000). The effects on haematological and biochemical profiles, the biomarkers of oxidative stress, and endocrine disruption were studied, and changes in RNA transcription were also monitored to obtain a comprehensive picture of toxicity. Fish exposure to high concentrations of NSAIDs (DCF 2000, IBP 2000) elicited numerous statistically significant changes (p < 0.05) in the endpoints investigated, with DCF being almost always more efficient than IBP. Compared to control fish, a decrease in total leukocyte count attributed to relative lymphopenia was observed. Plasma concentrations of total proteins, ammonia, and thyroxine, and enzyme activities of alanine aminotransferase (ALT), aspartate aminotransferase, and alkaline phosphatase (ALP) were significantly elevated in either group, as were the activities of certain hepatic antioxidant enzymes (superoxide dismutase, glutathione-S-transferase) in the DCF 2000 group. The transcriptomic profile of selected genes in the tissues of exposed fish was affected as well. Significant changes in plasma total proteins, ammonia, ALT, and ALP, as well as in the transcription of genes related to thyroid function and the antioxidant defense of the organism, were found even in fish exposed to the lower DCF concentration (DCF 20). As it was chosen to match DCF concentrations commonly detected in aquatic invertebrates (i.e., the potential feed source of fish), it can be considered "environmentally relevant". Future research is necessary to shed more light on the dietary NSAID toxicity to fish.

Accidental salinomycin intoxication in European fallow deer (Dama dama L.)

Salinomycin, belonging to ionophore antibiotics, has been used as a feed additive for poultry for its coccidiostatic effect. Poisoning by ionophore antibiotics has been reported in cattle and other sensitive animals due to the replacement of medicated feed and/or accidental overdoses. The aim of this paper is to report the toxicity of salinomycin for fallow deer and to describe the different levels of sensitivity of cervids to this substance. In the presented case study, a medicated feed containing ivermectin used for deworming red deer and fallow deer was accidentally contaminated with sodium salinomycinate in a concentration of 252.6 mg/kg. The contaminated feed was consumed by the animals over a period of four days. The mortality of fallow deer within 12 days was 58%. No mortality was recorded in the red deer. In the affected animals, clinical signs associated with acute and congestive heart failure were observed. The biochemical examination indicated prerenal azotaemia caused by circulatory insufficiency and ion imbalance. The histological examination revealed pronounced focal acute cardiomyopathy and massive subacute myopathy in the skeletal muscles.

River Sediments Downstream of Villages in a Karstic Watershed Exhibited Increased Numbers and Higher Diversity of Nontuberculous Mycobacteria

The impact of residential villages on the nontuberculous mycobacteria (NTM) in streams flowing through them has not been studied in detail. Water and sediments of streams are highly susceptible to anthropogenic inputs such as surface water flows. This study investigated the impact of seven residential villages in a karst watershed on the prevalence and species spectrum of NTM in water and sediments. Higher NTM species diversity (i.e., 19 out of 28 detected) was recorded downstream of the villages and wastewater treatment plants (WWTPs) compared to sampling sites upstream (i.e., 5). Significantly, higher Zn and lower silicon concentrations were detected in sediments inside the village and downstream of the WWTP's effluents. Higher phosphorus concentration in sediment was downstream of WWTPs compared to other sampling sites. The effluent from the WWTPs had a substantial impact on water quality parameters with significant increases in total phosphorus, anions (Cl-and N-NH3-), and cations (Na+ and K+). The results provide insights into NTM numbers and species diversity distribution in a karst watershed and the impact of urban areas. Although in this report the focus is on the NTM, it is likely that other water and sediment microbes will be influenced as well.

Nontuberculous Mycobacteria Prevalence in Aerosol and Spiders' Webs in Karst Caves: Low Risk for Speleotherapy

A total of 152 aerosol and spider web samples were collected: 96 spider’s webs in karst areas in 4 European countries (Czech Republic, France, Italy, and Slovakia), specifically from the surface environment (n = 44), photic zones of caves (n = 26), and inside (aphotic zones) of caves (n = 26), 56 Particulate Matter (PM) samples from the Sloupsko-Sosuvsky Cave System (speleotherapy facility; n = 21) and from aerosol collected from the nearby city of Brno (n = 35) in the Czech Republic. Nontuberculous mycobacteria (NTM) were isolated from 13 (13.5%) spider’s webs: 5 isolates of saprophytic NTM (Mycobacterium gordonae, M. kumamotonense, M. terrae, and M. terrae complex) and 6 isolates of potentially pathogenic NTM (M. avium ssp. hominissuis, M. fortuitum, M. intracellulare, M. peregrinum and M. triplex). NTM were not isolated from PM collected from cave with the speleotherapy facility although mycobacterial DNA was detected in 8 (14.3%) samples. Temperature (8.2 °C, range 8.0–8.4 °C) and relative humidity (94.7%, range 93.6–96.6%) of air in this cave were relatively constant. The average PM_2.5 and PM₁₀ mass concentration was 5.49 µg m⁻³ and 11.1 µg m⁻³. Analysed anions (i.e., F⁻, Cl⁻, NO₂⁻, SO₄²⁻, PO₄³⁻ and NO₃⁻) originating largely from the burning of wood and coal for residential heating in nearby villages in the surrounding area. The air in the caves with speleotherapy facilities should be monitored with respect to NTM, PM and anions to ensure a safe environment.

Nontuberculous Mycobacteria Prevalence in Bats' Guano from Caves and Attics of Buildings Studied by Culture and qPCR Examinations

A total of 281 guano samples were collected from caves (N = 181) in eight European countries (Bulgaria, Czech Republic, France, Hungary, Italy, Romania, Slovakia and Slovenia) and attics in the Czech R. (N = 100). The correlation of detection of mycobacteria between Ziehl–Neelsen (ZN) microscopy and culture examination and qPCR was strong. ZN microscopy was positive in guano from caves (58.6%) more than double than positivity in guano from attics (21.0%; p < 0.01). From 89 mycobacterial isolates (73 isolates from cave guano and 16 isolates from attics’ guano), 68 (76.4%) isolates of 19 sp., ssp. and complex were identified as members of three Groups (M. fortuitum, M.chelonae, and M. mucogenicum) and four complexes (M. avium, M. terrae, M.vaccae, and M.smegmatis). A total of 20 isolates (22.5%) belonged to risk group 1 (environmental saprophytes), 48 isolates (53.9%) belonged to risk group 2 (potential pathogens), and none of the isolates belonged to risk group 3 (obligatory pathogens). When comparing bat guano collected from caves and attics, differences (p < 0.01; Mann–Whitney test) were observed for the electrical conductivity, total carbon, total organic, and total inorganic carbon. No difference (p > 0.05; Mann–Whitney test) was found for pH and oxidation-reduction potential parameters.

Comprehensive fitness evaluation of common carp (Cyprinus carpio L.) after twelve weeks of atrazine exposure

Atrazine is frequently detected in surface waters and negatively affect physiological function in aquatic organisms. Even though numerous authors have intensively studied its toxicity, only limited information concerning the long-term fish exposure is available. The aim of this study was evaluation of chronic exposure in common carp. Fish were exposed to a range of atrazine concentrations (0.3 - environmentally relevant concentration; 300; 1000; and 3000 µg/l) for twelve weeks. The potential impact of atrazine exposure was studied using various markers (behaviour; biometrical characteristics; haematological, biochemical and oxidative stress indices and histopathological changes). Most alterations were recorded at the highest concentration (3000 µg/l) which is probably due to a combined effect of both the herbicide exposure and intensive parasite infection development during second week. This group was cancelled after three weeks due to adverse health status, which partly confirmed atrazine immunotoxicity. Chronic exposure resulted in long-term reduction in feed intake followed by a significant decrease in body weight and morphological changes in gill at 1000 µg/l. At the same concentration, significant alterations in haematological (e.g. increase in erythrocyte, leukocyte, lymphocytes and neutrophil counts as well as decrease in monocyte counts) and biochemical (e.g. changes in enzyme activities; increase in glucose; decrease in ammonia) indices were documented, especially during first three weeks. Similar trend, but not so intensive, was observed at 300 µg/l. Moreover, significant changes were observed in various indicators of oxidative stress. These alterations were highly variable with both increasing and decreasing trends depending on dose and analysed tissue. Significant changes, especially in white blood profile, enzyme activities and oxidative stress indices, were proven even at 0.3 µg/l. Obtained results indicate that chronic atrazine exposure of common carp can negatively influence many indicators of health status such as behaviour, immune response, haematological and biochemical profile, oxidative stress indices and organ histopathology.

Sodium chloride treatment effects on rainbow trout suffering from proliferative kidney disease caused by Tetracapsuloides bryosalmonae

The aim of the present study was to evaluate the effect of a long-term sodium chloride bath on rainbow trout Oncorhynchus mykiss naturally infected by Tetracapsuloides bryosalmonae. A total of 106 infected fish were divided into 2 groups. One group was left untreated and the other was treated with sodium chloride in increasing doses up a concentration of 0.8%. After 14 d, treatment was stopped and for a further 7 d the fish response to the sodium chloride bath was observed. Cumulative mortality was significantly lower in the treated group (19.2%) compared to the untreated group (31.5%) after 21 d. This corresponded to the lower but non-significant parasite intensity in kidney and spleen in the treated group after 14 d of treatment. However, lower prevalence of parasites in both tissues was recorded in the untreated group after 21 d of treatment, but a significant difference was observed only in spleen tissue. Furthermore, significant increases in leukocytes, hemoglobin, haematocrit, ferric reducing ability of plasma, and ceruloplasmin, and significant decreases in alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities were noticed in the treated group compared to the untreated group. In contrast, significant decreases in lysozyme concentration in the mucus and phagocyte oxidative burst in the blood were observed in the treated group. Histopathological examination revealed proliferative and reparative changes in parenchymatous tissues in the treated group. The 14- and 21-d salt bath used in rainbow trout with proliferative kidney disease was associated with a reduction in mortality and enhanced the reparative phase in the treated group.

Nontuberculous mycobacteria in the environment of Hranice Abyss, the world's deepest flooded cave (Hranice karst, Czech Republic)

Nontuberculous mycobacteria (NTM) are widely distributed in the environment. On one hand, they are opportunistic pathogens for humans and animals, and on the other hand, they are effective in biodegradation of some persistent pollutants. Following the recently recorded large abundance of NTM in extreme geothermal environments, the aim of the study was to ascertain the occurrence of NTM in the extreme environment of the water zone of the Hranice Abyss (HA). The HA mineral water is acidic, with large concentrations of free CO₂, and bacterial slimes creating characteristic mucilaginous formations. Both culture and molecular methods were used to compare the mycobacterial diversity across the linked but distinct ecosystems of HA and the adjacent Zbrašov Aragonite Caves (ZAC) with consideration of their pathogenic relevance. Six slowly growing NTM species (M. arupense, M. avium, M. florentinum, M. gordonae, M. intracellulare) and two rapidly growing NTM species (M. mucogenicum, M. sediminis) were identified in the water and in the dry zones at both sites. Proteobacteria were dominant in all the samples from both the HA and the ZAC. The bacterial microbiomes of the HA mineral water and HA slime were similar, but both differed from the microbiome in the ZAC mineral water. Actinobacteria, a phylum containing mycobacteria, was identified in all the samples at low proportional abundance. The majority of the detected NTM species belong among environmental opportunistic pathogens.

Effect of T-2 toxin-contaminated diet on common carp (Cyprinus carpio L.)

The T-2 toxin, a fungal metabolite produced by Fusarium molds, occurs in a range of agriculture products. Reduced availability of fish meal has led to increasing use of cereals as a source of protein in commercial aquaculture feeds, which has increased the potential for mycotoxin contamination. The purpose of this study was to investigate toxicity of T-2 toxin intake in common carp (Cyprinus carpio L.) using haematological, biochemical and immunological parameters and oxidative stress indices. In a four-week feeding trial, fish were fed a commercial diet with 5.3 mg/kg T-2 toxin added. Ingestion of contaminated diet did not lead to mortality of fish, probably due to lower feed intake. On the other hand, it significantly affected haematological variables such as haematocrit, haemoglobin, red blood cell counts leading to anemia and white blood cell counts leading to leukopenia due to lymphopenia. Plasma glucose concentration and alanine amino transferase activity showed a significant increase while triglycerides concentration decreased. Activity of ceruloplasmin was significantly decreased in plasma. Further, liver glutathione S-transferase activity was significantly increased and catalase activity decreased, in parallel with a significant increase in caudal kidney catalase activity and a decrease in glutathione peroxidase activity. Finally, lipid peroxidation (detected as malondialdehyde) was significantly increased in the liver and caudal kidney. Changes in non-specific immune response and cytokine levels in head kidney indicated immune system sensitivity to T-2 toxin. Overall, the results demonstrate that this feed-borne mycotoxin is able to induce anaemia and oxidative stress and cause changes in the immune response of common carp.

Effects of therapeutic formalin bath on selected indices in fish

OBJECTIVES

The aim of this study is to assess the effects of a treatment bath in a formalin solution on fish, focusing on haematological, biochemical and histopathological profiles.

METHODS

A total of 96 common carps (Cyprinus carpio) were randomly assigned to eight groups. Four experimental groups were placed in the test solution for 60 minutes. The concentration of the formalin bath was 0.17 ml/l (38% formaldehyde), with the water temperature of 20°C. The effects of the bath were monitored immediately (E0) and 24 hours (E24h), 48 hours (E48h) and 10 days (E10d) after the bath. There was a control group (C0, C24h, C48h, C10d) for each of the experimental groups.

RESULTS

Histopathological indices were strongly affected. Extensive changes were found on gill and skin immediately and also after 24 h, 48 h and 10 d of the formalin treatment bath. A plurality of mucinous elements was observed on the skin. Moreover, structural devastation of lamellas and numerous mucinous cells were observed on the gill. Changes were also found in haematological and biochemical indices.

CONCLUSIONS

It can be concluded that after applying the treatment bath in the formalin solution, the monitored profiles were affected immediately after the bath and also after 10 days (histopathological changes of skin and gill). Such significant impact of therapeutic formalin bath should be considered in treatment of fish.

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 effects of mycotoxin deoxynivalenol (DON) on haematological and biochemical parameters and selected parameters of oxidative stress in piglets

OBJECTIVES

Deoxynivalenol (DON) - trichothecene mycotoxin, is frequently detected in high concentrations in cereals in the temperate region of Europe. The aim of this study was to determine the effect of DON in feed on haematological and biochemical parameters and on oxidative stress in piglets.

METHODS

Two concentrations of DON in feedstuff for pigs were chosen: 0.6 mg/kg (group C) and 2.0 mg/kg (group M). Twelve weaned pigs were used in each group. Pigs were fed with naturally contaminated feed for 4 weeks. On days 14, 21 and at the end of the experiment (day 28) samples of blood were taken to determine haematological parameters, plasma biochemical parameters, ceruloplasmin activity and FRAP (ferric reducing ability of plasma).

RESULTS

The haematological variables did not show changes in response to contaminated diet with exception of the mean corpuscular volume, which was significantly decreased at the end of the experiment in the group M. A significant increase of alkaline phosphatase activity (140%, p<0.01) was found in the group M compared to the group C at the end of the experiment. A significant decrease was found on the day 21 in FRAP (85%, p<0.001) and on the day 28 in ceruloplasmin (75%, p<0.01) in the group M compared to the group C.

CONCLUSIONS

The decrease of FRAP and ceruloplasmin indicate a lowered ability of organism to scavenge reactive oxygen species. The higher concentration of DON in feedstuffs had a negative influence on the antioxidant ability of piglet's plasma.

Effect of β-1.3/1.6-D-glucan derived from oyster mushroom Pleurotus ostreatus on biometrical, haematological, biochemical, and immunological indices in rainbow trout (Oncorhynchus mykiss)

OBJECTIVES

Effect of long-term oral administration of three different concentrations (0.5, 1.0, and 2.0%) of micronized β-1.3/1.6-D-glucan derived from oyster mushroom (Pleurotus ostreatus, Hiratake) on biometrical, haematological, biochemical, and immunological indices of half-year-old rainbow trout (Oncorhynchus mykiss) was assessed in the study.

DESIGN

Rainbow trout were feed commercial feed pellets containing β-1.3/1.6-D-glucan in the concentrations of 0.5, 1.0, and 2.0% for 85 days. Biometrical indices consisted in total and standard length, body and liver weight, from which derived somatic parameters such as Fulton´s condition factor and hepatosomatic index were calculated. Haematological parameters were evaluated according to unified methods for haematological examination in fish. Plasma biochemical profile was analysed using biochemical analyser Konelab 20i and Easy Lyte Analyzer. A phagocyte cells metabolic activity (induced chemiluminescence of phagocytes) was determined as an immunological parameter by a microplate luminometric method on Immunotech LM-01T.

RESULTS

No clinical signs of behavioral, respiratory, or neurologic distress were observed in rainbow trout. Fish showed normal feeding behavior. As for biometric parameters, no significant changes in total and standard length, body weight, liver weight, as well as in condition factor and hepatosomatic index of experimental and control fish were found. In the course of the study, weight gains in rainbow trout were similar and continuous. Shifts in PCV (p<0.05), haemoglobin (p<0.05), and MCHC (p<0.01) were found within haematological indices. Plasma concentration of glucose, lactate, total protein, cholesterol, calcium, natrium, potassium (all p<0.05), albumins and chlorides (both p<0.01), as well as catalytic activities of ALT and AST (both p<0.05) were changed in the course of the study. A phagocyte cells metabolic activity (luminol-induced chemiluminescence) in rainbow trout was not altered by oyster mushroom β-1.3/1.6-D-glucan administration.

CONCLUSION

After long-term oral administration of three concentrations of micronized β-1.3/1.6-D-glucan derived from oyster mushroom (Pleurotus ostreatus, Hiratake) shifts in haematological and biochemical profiling were found in half-year-old rainbow trout (O. mykiss) in environmental conditions of a commercial rainbow trout fishery. Biometrical indices were not found significantly altered. No specific effect of β-glucan on immune system response of rainbow trout was found in the study. The use of β-glucan in prosperous, clinically healthy aquaculture is still an issue, nevertheless, its use in breedings endangered by stress stimuli, infectious diseases or adverse environmental factors is indisputable.

Comparison of diazinon toxicity to embryos of Xenopus laevis and Danio rerio; degradation of diazinon in water

The aim of this study was to determine the toxic effect of diazinon (organophosphate insecticide) to embryos of Xenopus laevis and Danio rerio. The 96-h LC₅₀ values showed higher toxicity of diazinon for X. leavis in standard solution (9.84 mg/L) compared to the pond water (12.64 mg/L). Teratogenic index for diazinon was 1.3 and 1.6, respectively. The 96-h LC₅₀ diazinon values demonstrated similar sensitivity of embryos D. rerio (8.21-9.34 mg/L) and X. laevis in standard test solutions. Our results reflect that direct application of diazinon into the water can be associated with significant risks to aquatic organisms.

The effects of Click 500 SC (terbuthylazine) on common carp Cyprinus carpio under (sub)chronic conditions

OBJECTIVES

Effects of the herbicide formulation Click 500 SC (terbuthylazine 500 g/l) on common carp Cyprinus carpio were assessed through biometric, biochemical, haematological and antioxidant indices, induction of xenobiotic metabolizing enzymes and histological examination of selected tissues.

DESIGN

The fish were exposed to the formulation with terbuthylazine concentrations of 380 ng/l (environmental concentration); 60 µg/l and 550 µg/l for up to 91 days. Haematological indices were assessed using unified methods of haematological examination in fish. Biochemical indices in plasma were measured by biochemical analyzer, ferric reducing ability of plasma (FRAP) and ceruloplasmin activity were determined spectrophotometrically. Concentration of total cytochrome P450, glutathione-S-transferase activity and glutathione content were assessed spectrophotometrically in liver. Activity of liver ethoxyresorufin-O-deethylase (EROD) activity was measured spectrofluorimetrically. Histopathological examination of liver, skin, gills, spleen, cranial and caudal kidney was performed by light microscopy.

RESULTS

An increase (p<0.05) was observed in hepatosomatic index and condition factor in fish from the environmental concentration. A decrease (p<0.05) in haemoglobin and mean corpuscular haemoglobin concentration (MCHC) was found in fish treated with terbuthylazine of 550 µg/l. There was a decline in mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) (p<0.05) in terbuthylazine of 60 µg/l and 550 µg/l. Triglycerides (TAG) (p<0.01) were elevated in all pesticide-treated groups. Alanine aminotransferase (ALT) (p<0.01) and phosphorus (p<0.05) decreased in fish exposed to terbuthylazine of 60 µg/l and 550 µg/l, while albumin (p<0.01) rised in the same groups. An elevation in natrium (p<0.05) in terbuthylazine of 550 µg/l and a rise in protein (p<0.01) in the concentrations of 380 ng/l and 550 µg/l were observed. Correlations between several indices were significant. Ceruloplasmin activity and FRAP were augmented (p<0.01) in the highest concentration tested. Examined xenobiotic detoxification systems were not significantly affected by the exposure. Non-specific histopathological changes were found in the gills and skin of the test fish.

CONCLUSION

The fish treated with terbuthylazine developed a disorder in several haematological and plasma biochemical indices. The levels of markers of oxidative stress increased in response to the exposure. Examined systems involved in detoxification of xenobiotics did not reflect long-term contact with the herbicide. Detected histological lesions were non-specific. The environmental concentration of terbuthylazin affected biometric indices of the test fish.

Effects of high dietary levels of Se-enriched yeast on tissues selenium content and meat quality traits - a model study in rats

OBJECTIVES

The aim of the trial was to evaluate effects of high dietary levels of Se-enriched yeast on selenium concentrations in muscle and liver tissue and on the meat quality traits in rats.

DESIGN

The experimental feed mixtures were fed to Wistar Albino rats for a period of 10 weeks. They differed in the dose and in the form of Se supplement. Supplemental dose of 0.3 mg.kg-1 of Se per one kilogram of feed was used in group I (n = 10, sodium selenite) and in group II (n = 10, Se-enriched yeast). Elevated dose 2 mg.kg-1 Se per one kilogram of feed was used in group III (n = 10, sodium selenite) and in group IV (n = 10, Se-enriched yeast).

RESULTS

The use of elevated dietary Se level (2 mg.kg-1) in the form of sodium selenite did not increase lipid oxidation (malondialdehyde content) in muscles nor influenced meat quality traits. The use of elevated dietary Se level in the form of Se-enriched yeast resulted in higher Se muscle concentrations accompanied by increased of malondialdehyde content. The meat quality traits remained unaffected.

CONCLUSION

High selenium concentrations in muscle produced by Se-enriched yeast were accompanied by elevated MDA levels, but it did not negatively influence meat quality traits.

Effects of subchronic exposure to Spartakus (prochloraz) on common carp Cyprinus carpio

OBJECTIVES

The aim of the study was to investigate effects of the fungicide formulation Spartakus (prochloraz 450 g.L-1) on common carp Cyprinus carpio through biometric, biochemical, haematological and antioxidant indices, induction of xenobiotic metabolizing enzymes and histological examination of selected tissues.

DESIGN

The test was performed on juvenile fish, which was exposed to Spartakus (concentrations of prochloraz: 0.05; 0.15 and 0.38 mg.L-1) for 28 days. Haematological indices were assessed using unified methods of haematological examination in fish. Plasma biochemical indices were determined by biochemical analyzer. Concentration of total cytochrome P450 (CYP), glutathione (GSH) content and glutathione-S-transferase (GST) activity were determined spectrophotometrically in hepatopancreas. Activity of liver ethoxyresorufin-O-deethylase (EROD) activity was measured spectrofluorimetrically. Ferric reducing ability of plasma (FRAP) and ceruloplasmin activity were assessed spectrophotometrically. Histological changes in samples of hepatopancreas, skin, gills, spleen, head kidney and caudal kidney were examined by light microscopy.

RESULTS

There was a significant rise in hepatosomatic index (HSI) (p<0.01), CYP and EROD (p<0.05) of fish exposed to prochloraz of 0.15 and 0.38 mg.L-1 whereas GST was induced by all concentrations tested and GSH by 0.38 mg.L-1 (p<0.05). Red blood cell count decreased significantly (p<0.05) in prochloraz of 0.05 and 0.15 mg.L-1. Plasma potassium increased (p<0.01) in all Spartakus treated groups, a decline in total protein (p<0.05), ALT, Na+ and Ca (p<0.01) was found in fish exposed to prochloraz of 0.38 mg.L-1. Ceruloplasmin activity was elevated (p<0.05) in the highest concentration tested, FRAP declined (p<0.05) in the same group. Histopathological changes in gills were demonstrated in all pesticide treated groups, with a decreased activity of skin mucous cells in prochloraz of 0.38 mg.L-1.

CONCLUSION

The subchronic exposure to Spartakus influenced HSI, induced xenobitic metabolizing enzymes, initiated a disorder of selected plasma indices and a decline in red blood cell count, caused minor histological impairment, and affected antioxidant activities of the test fish.

Effects of subchronic exposure to Successor 600 (pethoxamid 600 g L-1) on common carp Cyprinus carpio

OBJECTIVES

We investigated the effects of the herbicide preparation Successor 600 on biochemical and haematological indices and the histolopathological parameters of common carp after 28 day exposure. Furthermore, the hepatosomatic index and induction of xenobiotic metabolizing enzymes and biomarkers were assessed.

DESIGN

Juvenile fish were exposed to sublethal concentrations of Successor(R) 600 (0.06 mg L-1, 0.22 mg L-1 or 0.60 mg L-1) for 28 days. Haematological indices were assessed using unified methods of haematological examination in fish. Plasma biochemical indices were measured by biochemical analyzer, the vitellogenin concentration in male fish plasma was estimated by direct sandwich ELISA. In hepatopancreas, ethoxyresorufin-O-deethylase (EROD) activity was measured spectrofluorimetrically, concentration of total cytochrome P450 (CYP), glutathion (GSH) content and glutathion-S-transferase (GST) activity were determined spectrophotometrically. Histological changes in samples of hepatopancreas, skin, gills, spleen, head kidney and trunk kidney were examined by light microscopy.

RESULTS

Haemoglobin, MCH and MCHC were significantly (p<0.05) reduced in fish treated with Successor(R) 600 of 0.22 and 0.60 mg L-1. LDH was enhanced (p<0.05), in the highest concentration of the preparation. Vitellogenin was detected in all male fish, with no difference between groups. HSI, GSH and GST were elevated (p<0.05), owing to the exposure, whereas CYP and EROD were not affected. Slight histopathological changes were demonstrated in skin, gills and hepatopancreas, with steroid tissue in head kidney samples of 0.60 mg L-1 treated fish.

CONCLUSION

Successor 600 affected the haematological profile of the treated fish, while the effects on biochemical indices were less expressed. Male plasma vitellogenin concentrations were not indicative of estrogen disruptive effects after 28 days. The importance of GSH and GST for the metabolisation were demonstrated. In contrast, CYP and EROD were not influenced by any concentration tested. HSI was found to reflex pollution with Successor 600. Histopathological indices caused by the treatment were observed in various tissue samples of the treated fish.

A review: oxidative stress in fish induced by pesticides

The knowledge in oxidative stress in fish has a great importance for environmental and aquatic toxicology. Because oxidative stress is evoked by many chemicals including some pesticides, pro-oxidant factors' action in fish organism can be used to assess specific area pollution or world sea pollution. Hepatotoxic effect of DDT may be related with lipid peroxidation. Releasing of reactive oxygen species (ROS) after HCB exposure can be realized via two ways: via the uncoupling of the electron transport chain from monooxygenase activity and via metabolism of HCB major metabolite pentachlorophenol. Chlorothalonil disrupts mitochondrial metabolism due to the impairment of NADPH oxidase function. Activation of spleen macrophages and a decrease of catalase (CAT) activity have been observed after endosulfan exposure. Excessive release of superoxide radicals after etoxazole exposure can cause a decrease of CAT activity and increase phagocytic activity of splenocytes. Anticholinergic activity of organophosphates leads to the accumulation of ROS and resulting lipid peroxidation. Carbaryl induces changes in the content of glutathione and antioxidant enzymes activities. The antioxidant enzymes changes have been observed after actuation of pesticides deltamethrin and cypermethrin. Bipyridyl herbicides are able to form redox cycles and thereby cause oxidative stress. Low concentrations of simazine do not cause oxidative stress in carps during sub-chronic tests while sublethal concentrations of atrazin can induce oxidative stress in bluegill sunfish. Butachlor causes increased activity of superoxide dismutase -catalase system in the kidney. Rotenon can inhibit the electron transport in mitochondria and thereby increase ROS production. Dichloroaniline, the metabolite of diuron, has oxidative effects. Oxidative damage from fenpyroximate actuation is related to the disruption of mitochondrial redox respiratory chain. Low concentration of glyphosate can cause mild oxidative stress.

Effects of subchronic exposure to LASSO MTX (alachlor 42% W/V) on hematological indices and histology of the common Carp, Cyprinus carpio L

The aim of the study was to evaluate subchronic toxic effects of the preparation LASSO MTX (alachlor 42% W/V) on hematological indices and histology of the common carp (Cyprinus carpio L.). In carp exposed for 28 days to LASSO MTX in the concentration of 2,400 microg L(-1), significant differences (p < 0.05), were detected in all indices of the erythrocyte profiles tested except hematocrit (PCV) when compared to controls. At a lower exposure (240 microg L(-1)) concentration of blood hemoglobin and mean corpuscular hemoglobin were significantly reduced. In contrast, no influence of the preparation on leucopoiesis was demonstrated, and only slight changes were observed in histopathological indices.

Effects of subchronic metribuzin exposure on common carp (Cyprinus carpio)

OBJECTIVES

Effects of metribuzin on biochemical and haematological indices, induction of specific biomarkers and impacts on biometric parameters of Cyprinus carpio were investigated for subchronic conditions.

METHODS

Juvenile fish were exposed to 0.175 mg.L-1 or 1.75 mg.L-1 metribuzin for 28 days. Haematological indices were assessed using unified methods of haematological examination in fish. Biochemical indices were determined by biochemical analyzer, hepatic vitellogenin content was estimated by direct sandwich ELISA. Cytochrome P450 concentration and ethoxyresorufin O-deethylase activity were measured in liver spectrophotometrically and spectrofluorimetrically, respectively.

RESULTS

Increased haematocrit and RBC count were found in fish exposed to 1.75 mg.L-1 metribuzin compared to control fish (p<0.05). Other indices contents and biomarkers levels were not significantly changed by either concentration of metribuzin.

CONCLUSION

Sublethal metribuzin pollution may have adverse impacts on haematological parameters in common carp.

Mercury in human hair as an indicator of the fish consumption

OBJECTIVES

Mercury and most of its compounds are extremely toxic and should be handled with care. It can be inhaled and absorbed through the skin and mucous membranes. The most toxic forms of mercury are its organic compounds such as dimethylmercury and methylmercury. Fish have a natural tendency to accumulate mercury. Methylmercury is produced by microbial methylation of inorganic mercury in water sediment then it infiltrates the food chain and it consequently accumulates in fish. Fish are the main source of methylmercury in human food. Mercury is transferred into a hair; and this can be than used to monitor the long-term exposure to mercury. The content of mercury in hair depends on the frequency of fish consumption. The aim of our study was to compare mercury content in the hair of children that had various amounts of fish consumption (increased or reduced).

DESIGN

Total mercury content in hair was determined by direct method of cold vapors using an AMA 245 analyzer. A total of 174 hair samples from the children (9-17 years old) were analyzed. In this study, the following localities were compared: Neratovice (n=42), Jeseníky (n=44), Prague (n=59) in Czech Republic and Olsztyn in Poland (n=29). Every sample was accompanied with questionnaire about age, gender, regions, amalgam fillings and fish consumption.

RESULTS

We did not find a correlation between the content of mercury in hair with age, gender or amalgam fillings. We did find a correlation between fish consumption and the amount of mercury found in the hair samples.

CONCLUSION

The amount of mercury in hair increases with more frequent consumption of freshwater and marine fish.