Stress response in silver catfish (Rhamdia quelen) exposed to the essential oil of Hesperozygis ringens.

This study investigated the effects of prolonged exposure of silver catfish (Rhamdia quelen) to the essential oil (EO) of Hesperozygis ringens. Ventilatory rate (VR), stress and metabolic indicators, energy enzyme activities, and mRNA expression of adenohypophyseal hormones were examined in specimens that were exposed for 6 h to 0 (control), 30 or 50 µL L(-1) EO of H. ringens in water. Reduction in VR was observed in response to each treatment, but no differences were found between treatments. Plasma glucose, protein, and osmolality increased in fish exposed to 50 µL L(-1). Moreover, lactate levels increased after exposure to both EO concentrations. Plasma cortisol levels were not changed by EO exposure. Fish exposed to 30 µL L(-1) EO exhibited higher glycerol-3-phosphate dehydrogenase (G3PDH) activity, while exposure to 50 µL L(-1) EO elicited an increase in glucose-6-phosphate dehydrogenase (G6PDH), fructose-biphosphatase (FBP), and 3-hydroxyacyl-CoA-dehydrogenase (HOAD) activities compared with the control group. Expression of growth hormone (GH) only decreased in fish exposed to 50 µL L(-1) EO, while somatolactin (SL) expression decreased in fish exposed to both concentrations of EO. Exposure to EO did not change prolactin expression. The results indicate that GH and SL are associated with energy reorganization in silver catfish. Fish were only slightly affected by 30 µL L(-1) EO of H. ringens, suggesting that it could be used in practices where a reduction in the movement of fish for prolonged periods is beneficial, i.e., such as during fish transportation.

Alterations in carbohydrate and protein metabolism in silver catfish (Rhamdia quelen) exposed to cadmium.

Changes in carbohydrate and protein metabolism were studied in silver catfish Rhamdia quelen exposed to cadmium (0; 0.236 or 0.414 mg/L) during 7 and 14 days. After exposure time the fish were exposed to recovery period (water without cadmium), during 7 and 14 days. Different alterations in the metabolic parameters were observed such as an increase in lactate, protein, amino acid and ammonia levels as well as a reduction in glucose values after the exposure periods in liver. In muscle, glycogen and glucose values enhanced after cadmium exposure at both concentrations for 7 days; however, at 0.414 mg/L cadmium, protein levels decreased while amino acids and ammonia levels enhanced. An increase in the lactate values was found in plasma after 7 days of exposure and a reduction in the lactate, glucose and protein levels occurred after 14 days of exposure. Results indicated that the metabolic alterations after cadmium exposure were dependent on the tissue type and exposure time. Cadmium exposure for 14 days and recovery period also of 14 days seem to be less harmful to the liver and muscle. However, even after recovering from some changes, fish health may be affected making them more sensitive to some environmental changes.

Fish anesthesia: effects of the essential oils of Hesperozygis ringens and Lippia alba on the biochemistry and physiology of silver catfish (Rhamdia quelen).

The anesthetic activities of the essential oils (EOs) of Hesperozygis ringens (EOHR) and Lippia alba (EOLA) and their effects in silver catfish (Rhamdia quelen) after anesthesia and recovery were investigated. Fish (32.19 ± 1.24 g) were submitted to one of the following treatments for each EO: basal group, control, or anesthesia (150, 300, or 450 µL L(-1) EO). After that the anesthesia was induced or simulated and the biometric measurements were completed, fish were transferred to anesthetic-free aquaria to allow for recovery. Fish were sampled at 0, 15, 30, 60, and 240 min after recovery. At time 0 of recovery, the ventilatory rate was lower in the groups anesthetized with either EO. In comparison with the basal group, control fish showed an increase in plasma glucose, aspartate aminotransferase (AST), and Na(+) levels and a reduction in Na(+)/K(+)-ATPase activity at 0 min of recovery. Plasma levels of ammonia and Na(+) were lower in the fish anesthetized with EOLA (450 µL L(-1)) and EOHR (all concentrations), respectively, than in the control fish. Additionally, lactate, AST, alanine aminotransferase, K(+) plasma levels, and gill Na(+)/K(+)-ATPase and H(+)-ATPase activities were higher in the fish anesthetized with either EOHR or EOLA than in the control fish. The EOs promoted slight changes in silver catfish that enabled both an adaptive response and the recovery of most of the measured parameters after 240 min regardless of concentration or EO that was used. These findings support the use of EOHR and EOLA as anesthetics for fish.

Herbicide clomazone effects on δ-aminolevulinic acid activity and metabolic parameters in Cyprinus carpio.

The objective of this study was to investigate δ-aminolevulinic acid (δ-ALA-D) activity and metabolic parameters of Cyprinus carpio exposed to clomazone herbicide. Fish were exposed 2.5, 5, 10 and 20 mg L(-1) of clomazone for 192 h. Results indicated that δ-ALA-D activity was decreased in the gills at concentrations of 5 and 10 mg L(-1). Liver glycogen increased, while muscle and gill glycogen levels decreased at 5, 10 and 20 mg L(-1). Glucose was increased in the gills and plasma. Lactate decreased in the gills and liver and increased in the muscle. Protein and amino acids levels increased in the liver and gills and decreased in the muscle. At a clomazone concentration of 20 mg L(-1), ammonia increased in the gills and muscle and decreased in the liver. The results indicated that the metabolic parameters of glycogen, lactate, protein and amino acids in liver, muscle and gills, blood glucose levels, and the enzyme δ-ALA-D in gills may be useful indicators of clomazone toxicity in carp.

Oxidative stress in carp exposed to quinclorac herbicide under rice field condition.

This study evaluated parameters of oxidative stress and antioxidant profile in fish after herbicide exposure. Cyprinus carpio were exposed to quinclorac (initial concentration 344.60µg/L) for 7, 30, and 90 days under rice field condition. Thiobarbituric acid-reactive substances (TBARS) were evaluated in brain, liver and muscle tissues, and protein carbonyl in liver. Enzymatic parameters such as catalase (CAT) and gluthatione S-transferase (GST) activities also were studied in liver. TBARS levels fluctuated in the brain showing increase in 7 days and decrease in 30 days, while in liver it was observed increase in 7 and 30 days, as well as in muscle after 30 and 90 days. The protein carbonyl was also increased after 30 and 90 days of herbicide exposure. CAT and GST activities were decreased after 30 and 90 days, respectively. The alterations observed suggest that a commercial formulation containing quinclorac causes oxidative damage in different tissues of carp after a long time of exposure. This study pointed out the importance of quinclorac toxicity considering the concentration used in rice fields.

Nitrogenous and phosphorus excretions in juvenile silver catfish (Rhamdia quelen) exposed to different water hardness, humic acid, and pH levels.

This study examined ammonia, urea, creatinine, protein, nitrite, nitrate, and phosphorus (P) excretion at different water hardness, humic acid, or pH levels in silver catfish (Rhamdia quelen) juveniles. The fish were exposed to different levels of water hardness (4, 24, 50, or 100 mg L(-1) CaCO3), humic acid (0, 2.5, or 5.0 mg L(-1)), or pH (5.0, 6.0, 7.0, 8.0, or 9.0) for 10 days. The overall measured nitrogen excretions were 88.1% (244-423 µmol kg(-1 )h(-1)) for ammonia, 10.9% (30-52 µmol kg(-1 )h(-1)) for creatinine, 0.02% (0.05-0.08 µmol kg(-1 )h(-1)) for protein, 0.001 % (0.002-0.004 µmol kg(-1 )h(-1)) for urea, 0.5% (0.64-3.6 µmol kg(-1 )h(-1)) for nitrite, and 0.5% (0.0-6.9 µmol kg(-1 )h(-1)) for nitrate, and these proportions were not affected by water hardness or humic acid levels. The overall P excretion in R. quelen was 0.14-2.97 µmol kg(-1) h(-1). Ammonia excretion in R. quelen usually was significantly higher in the first 12 h after feeding, and no clear effect of water hardness, humic acid levels, and pH on this daily pattern of ammonia excretion could be observed. Water hardness only affected the ammonia and P excretion of R. quelen juveniles in the initial and fifth days after transfer, respectively. The exposure of this species to humic acid increased ammonia excretion after 10 days of exposure but did not affect P excretion. An increase in pH decreased ammonia and increased creatinine excretion but did not change P excretion in R. quelen. Therefore, when there is any change on humic acid levels or pH in the culture of this species, nitrogenous compounds must be monitored because their excretion rates are variable. On the other hand, P excretion rates determined in the present study are applicable to a wide range of fish culture conditions.

Toxicological responses of Cyprinus carpio exposed to the herbicide penoxsulam in rice field conditions.

Cyprinus carpio fish were exposed to penoxsulam (Ricer) in field conditions. The experiment in the rice field was carried out for 7, 21 and 72 days. Oxidative stress parameters and antioxidant profile were studied. The acetylcholinesterase (AChE) enzyme activity in the brain was increased after 7 days and reduced after 21 and 72 days of the experiment in the rice field. The AChE activity in muscle was reduced only after 72 days of exposure. Thiobarbituric acid-reactive species were increased in the liver, brain and muscle at 7 days of the trial, reduced at 21 days in the brain and unaltered after 72 days of exposure in muscle. However, an increase in this parameter in the brain and liver was observed. Liver glutathione S-transferase was reduced at 7 days, unchanged at 21 days and increased after 72 days of exposure. Catalase of the liver changed only in the second experimental period, when it was reduced. Liver protein carbonyl was reduced at 7 days and increased at 21 and 72 days of exposure. This study shows long-term effects of rice herbicide at environmentally relevant concentrations on toxicological parameters in different tissues (brain, muscle and liver) of Cyprinus carpio.

Toxicological responses of Cyprinus carpio after exposure to a commercial herbicide containing imazethapyr and imazapic.

Cyprinus carpio was exposed to imazethapyr and imazapic at laboratory and at field conditions. The laboratory experiment was carried out for 7 days and at rice field for 7, 30 and 90 days. Oxidative stress parameters and antioxidant profile were studied as well as metabolic parameters. After 7 days, brain AChE activity increases in laboratory and field, but in muscle, reduction was observed only in laboratory. At the same period, brain and muscle TBARS and liver CAT increase in the laboratory. Metabolic parameters showed changes in both conditions and exposure periods. After 30 days in rice field, brain AChE activity decreases and in muscle it was enhanced. After 90 days in field, only muscle AChE activity was reduced. The disorders in oxidative stress parameters and metabolism remained, indicating mainly a protein catabolism. This study pointed out short- and long-term effects of rice herbicides at environmentally relevant concentrations on toxicological parameters in tissues of C. carpio.

Oxidative stress biomarkers in Cyprinus carpio exposed to commercial herbicide bispyribac-sodium.

Cyprinus carpio were exposed under field conditions to 20.87 microg l(-1) of commercial herbicide bispyribac-sodium (Nominee, SC), during 7, 21 and 72 days. Enzymatic parameters such as catalase (CAT), glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities, as well as thiobarbituric acid-reactive substances (TBARS) and protein carbonyl contents were studied in different tissues. After 7 days of exposure, GST activity decreased. At the same period, brain AChE activity increased, but a reduction of activity was observed in muscle tissue. Brain TBARS levels increased at 7 days. After 21 days of exposure liver CAT levels and muscle AChE activities decreased. In the same period, liver protein carbonyl and muscle TBARS increased. After 72 days of exposure in the field, AChE activity was reduced in both brain and muscle. Protein carbonyl contents in liver and brain TBARS levels increased. Muscle AChE activity, TBARS and protein carbonyl can be used as biomarkers of exposure to the herbicide bispyribac-sodium. This study demonstrates effects of exposure to bispyribac-sodium under rice field conditions on oxidative stress parameters in tissues of Cyprinus carpio.

Sedative effect of 2-phenoxyethanol and essential oil of Lippia alba on stress response in gilthead sea bream (Sparus aurata).

The anesthetic efficacy of the essential oil of Lippia alba (EOLA) in Sparus aurata was evaluated by induction and recovery times of anesthesia. After, specimens were exposed to anesthetics low concentrations for 4h, under nonstress or stress conditions. Range 100-300 µL L(-1) EOLA induced anesthesia. Plasmatic cortisol, glucose, lactate, and osmolality enhanced after EOLA exposure in the undisturbed (UF) and stressed fish (SF). Lower corticotropin-releasing hormone binding-protein expression occurred in SF/EOLA compared with 2-PHE/stress combination or to EOLA/undisturbed conditions. Stress processes reduced prolactin (PRL) expression in the control fish, while UF exhibited reduced PRL levels after exposure to both anesthetics. Proopiomelanocortin (POMCa) mRNA was higher after 2-PHE exposure in SF compared to control; POMCb expression was higher in SF/EOLA in contrast to control and UF/EOLA conditions. Thus, EOLA was an effective anesthetic, but it was unable to prevent a stress response in S. aurata; while 2-PHE is advisable to sedate S. aurata without causing stress, but it was not effective at preventing a stress response in the present work.

The effects of ammonia and water hardness on the hormonal, osmoregulatory and metabolic responses of the freshwater silver catfish Rhamdia quelen.

The aim of the present study was to assess the effects of ammonia and water hardness on endocrine, osmoregulatory and metabolic parameters in silver catfish (Rhamdia quelen). The specimens (60-120g) were subjected to six treatments in triplicate, combining three levels of un-ionized ammonia (NH3) (0.020±0.008mg/L [1.17±0.47µM], 0.180±0.020mg/L [10.57±1.17µM] and 0.500±0.007mg/L [29.36±0.41µM]) and two levels of water hardness (normal: 25mgCaCO3/L and high: 120mgCaCO3/L), and sampled after two exposure times (1 and 5 days post-transfer). Plasma cortisol, metabolites, osmolality and ionic values were determined concomitantly with the mRNA expression levels of different adenohypophyseal hormones (growth hormone, GH; prolactin, PRL; and somatolactin, SL). Previously, full-length PRL and SL as well as ß-actin cDNAs from R. quelen were cloned. Exposure to high NH3 levels enhanced plasma cortisol levels in fish held under normal water hardness conditions but not in those kept at the high hardness value. The increase in water hardness did not alter plasma metabolites, whereas it modulated the osmolality and ion changes induced by high NH3 levels. However, this hardness increase did not lead to the decreased GH expression that was observed 5 days after exposure to 0.18mg/L NH3 in fish held at the normal water hardness level, whereas PRL expression was enhanced after one day of exposure under the increased hardness conditions. Additionally, SL expression decreased in specimens exposed for 5 days to 0.18mg/L NH3 and maintained at the high water hardness level. The results showed that increasing water hardness attenuated the hormonal parameters evaluated in R. quelen specimens exposed to high NH3 levels, although plasma metabolism do not appear to suffer major changes.

Comparative study on effects of dietary with diphenyl diselenide on oxidative stress in carp (Cyprinus carpio) and silver catfish (Rhamdia sp.) exposed to herbicide clomazone.

The study investigated the capacity of diphenyl diselenide [(PhSe)2] (3.0mg/kg), on reduce the oxidative damage in liver, gills and muscle of carp and silver catfish exposed to clomazone (192h). Silver catfish exposed to clomazone showed increased thiobarbituric acid-reactive substance (TBARS) in liver and muscle and protein carbonyl in liver and gills. Furthermore, clomazone in silver catfish decrease non-protein thiols (NPSH) in liver and gills and glutathione peroxidase and ascorbic acid in liver. (PhSe)2 reversed the effects caused by clomazone in silver catfish, preventing increases in TBARS and protein carbonyl. Moreover, NPSH and ascorbic acid were increased by values near control. The results suggest that (PhSe)2 attenuated the oxidative damage induced by clomazone in silver catfish. The clomazone no caused an apparent situation of oxidative stress in carp, showing that this species is more resistant to this toxicant. Altogether, the containing (PhSe)2 diet helps fish to increase antioxidants defenses.

Anesthesia of tambaqui Colossoma macropomum (Characiformes: Serrasalmidae) with the essential oils of Aniba rosaeodora and Aniba parviflora and their major compound, linalool

The aim of this study was to determine the anesthetic efficacy of the essential oils (EOs) of Aniba rosaeodora (EOAR) and Aniba parviflora (EOAP) and one of their main compounds, linalool, in two forms: synthetic and extracted from EOAR (linalool-AR) in tambaqui (Colossoma macropomum). In the first experiment, the anesthetic induction and recovery of juveniles exposed to 25- 200 µL L-1 of EOAR or 50- 300 µL L-1 of EOAP or synthetic linalool or linalool-AR was evaluated. The second experiment observed the behavioral effects of long-term exposure (12h) of these EOs and linalools (5 and 10 µL L-1). Fish exposed to 50-200 µL L-1 of EOAR and 100-300 µL L-1 of EOAP and both linalools reached deep anesthesia between 1-10 min. Induction time for all anesthesia stages decreased with the increasing concentration of the anesthetics. Linalool-AR showed lengthier time for anesthesia induction in some stages and for recovery at 100 and 200 µL L-1 in comparison to synthetic linalool. Normal equilibrium and swimming behavior was observed in fish exposed to the EOs and linalools throughout the 12 h of exposure. In conclusion, both EOs and linalools can be used as anesthetics and sedatives in tambaqui.(AU)

O objetivo deste trabalho foi determinar a eficácia anestésica dos óleos essenciais (OEs) de Aniba rosaeodora (OEAR) Aniba parviflora (OEAP) e um de seus compostos majoritários, linalol, em duas formas: sintética e extraída a partir de OEAR (linalol-AR) em tambaqui (Colossoma macropomum). No primeiro experimento avaliou-se a indução anestésica e a recuperação de juvenis expostos a 25- 200 µL L-1 de EOAR ou 50- 300 µL L-1 de EOAP ou linalol sintético ou linalol-AR. No segundo experimento observaram-se os efeitos comportamentais de uma longa exposição (12h) a estes OEs e linalois (5 e 10 µL L-1). Os peixes expostos a 50-200 µL L-1 de EOAR e 100-300 µL L-1 de OEAP e ambos os linalois alcançaram anestesia profunda entre 1-10 min. Tempo de indução a todos os estágios de anestesia diminuiu com o aumento na concentração dos anestésicos. Linalol-AR levou um maior tempo para induzir anestesia e para recuperação com 100 e 200 µL L-1 em comparação ao composto sintético. Peixes expostos aos OES e linalois por 12 h apresentaram equilíbrio e comportamento natatório normais. Em conclusão, tanto os OEs como o linalol sintético ou natural de AR podem ser usados como anestésicos e sedativos em tambaqui.(AU)

Anesthesia and sedation of map treefrog (Hypsiboas geographicus) tadpoles with essential oils / Anestesia e sedação de girinos da perereca geográfica Hypsiboas geographicus com óleos essenciais

ABSTRACT: The goal of this study was to investigate the sedative and anesthetic properties of essential oils (EOs) in map treefrog tadpoles (Hypsiboas geographicus) and to determine the sedation and deep anesthesia induction times as well as the recovery time. The tadpoles were exposed to one of the EOs from three plant species: Aniba rosaeodora (EOAR - 25, 50, 100 or 200µL L-1), Lippia origanoides (EOLO - 13, 25, 50, 100 or 200µL L-1), and Lippia alba (either chemotype citral [EOL-C - 25, 50, 100 or 200µL L-1] or linalool [EOL-L - 50, 75, 100 or 200µL L-1]) (n = 8 per replicate). The tadpoles exposed to 25 and 50µL L-1 EOL-C and EOL-L, respectively, were not anesthetized within 30min (the maximum time of observation), and those exposed to 200µL L-1 EOLO did not recover within 30min. Sedation, deep anesthesia and recovery times showed a concentration-dependent relationship for all EOs tested, with the exception of the recovery with EOLO. The results allowed concluding that all investigated EOs can be used to anesthetize tadpoles of H. geographicus, but the use of EOLO must not exceed 100µL L-1.

RESUMO: O objetivo deste estudo foi investigar as propriedades sedativas e anestésicas de óleos essenciais (OEs) em girinos da perereca Hypsiboas geographicus e determinar os tempos de indução à sedação e anestesia profunda, bem como o de recuperação. Os girinos foram expostos a um dos OEs de três espécies de plantas: Aniba rosaeodora (OEAR - 25, 50, 100 ou 200µL L-1), Lippia origanoides (OELO - 13, 25, 50, 100 ou 200µL L-1 ) ou Lippia alba quimiotipos citral (OEL-C - 25, 50, 100 ou 200µL L-1) ou linalol (OEL-L - 50, 75, 100 ou 200µL L-1) (n = 8 cada repetição). Girinos expostos a 25 e 50µL L-1 OEL-C e OEL-L, respectivamente, não foram anestesiados dentro de 30min (tempo máximo de observação) e aqueles expostos a 200µL L-1 OELO não recuperaram dentro de 30min. Os tempos de sedação, anestesia profunda e recuperação apesentaram uma relação concentração-resposta para todos os OEs testadas, exceto a recuperação com OELO. Os resultados permitem concluir que todos os OEs investigados podem ser usados para anestesiar os girinos de H. geographicus, mas o uso de OELO não deve ser superior a 100µL L-1.

Assessment of oxidative stress and metabolic changes in common carp (Cyprinus carpio) acutely exposed to different concentrations of the fungicide tebuconazole.

The aim of this research is to determine the lethal concentration (LC(50-96 h)) of fungicide tebuconazole for common carp (Cyprinus carpio) and to investigate the occurrence of oxidative stress and metabolic changes after acute exposure to different concentrations of tebuconazole. For this purpose, several parameters were assessed as whole-body levels of thiobarbituric acid-reactive substance (TBARS), protein carbonyl, catalase, superoxide dismutase, glutathione S-transferase, nonprotein thiols, ascorbic acid, glycogen, glucose, lactate, protein, amino acids and ammonia in tebuconazole-exposed fish. The calculated LC(50-96 h) was 2.37 mg L(-1). Fish exhibited significant increase in TBARS levels in all concentrations used while the enzymatic and nonenzymatic antioxidants were decreased. Among the metabolic parameters, glycogen and glucose increased at 1.19 mg L(-1) and protein levels decreased at 1.78 and 2.37 mg L(-1). In conclusion, the fish health was adversely affected by exposure to tebuconazole, and those changes can compromise animal survival in the natural environment. The results indicate that the some of the parameters measured like a possible biomarkers of exposure to tebuconazole for this species of fish.

Exposure to tebuconazol in rice field and laboratory conditions induces oxidative stress in carp (Cyprinus carpio).

Pesticides can have an effect on the biochemical and physiological functions of living organisms. The changes seen in fish and their response to pesticides can be used as an example for vertebrate toxicity. In this study, carp fish (Cyprinus carpio) were exposed to different concentrations of tebuconazol fungicide, by rice field (31.95 µg/L) and laboratory (33.47 and 36.23 µg/L) conditional testing, during a 7 day period. Parameters such thiobarbituric acid-reactive substance levels (TBARS), protein carbonyl, catalase, glutathione S-transferase and acetylcholinesterase activities were studied, using the liver, brain and white muscle of the fish. The field experiment showed that the TBARS levels were increased in all the analyzed tissues. Similarly, the protein carbonyl of the liver and the brain AChE activity increased after 7 days. The laboratory experiment demonstrated that the TBARS levels in the liver were increased in both of the concentration tests. TBARS levels in the muscle increased only by the lowest test concentration. On the other hand, the protein carbonyl was increased only by the highest concentration. The results indicate that the tebuconazol exposure from the field and laboratory conditions directly affected the health of the fish, showing the occurrence of oxidative stress.

Assessment of oxidative stress in Rhamdia quelen exposed to agrichemicals.

Due to the proximity of crop and fish culture areas, some agrichemicals that could be harmful for fish could enter into fishponds by different ways, such as by leaching through rain. Rhamdia quelen (Teleostei) were exposed to sublethal concentrations of methyl parathion (MP), a glyphosate based herbicide (Gly), and tebuconazole (Teb). The liver of R. quelen exposed to MP and Teb showed enhanced levels of thiobarbituric acid reactive substances (TBARS), higher than in the control fish (56% and 59%, respectively). In contrast, Gly did not alter the TBARS generation. The protein carbonyl content increased only in fish exposed to Teb. Fish exposed to the three agrichemicals showed a significant decrease of catalase activity (52%, 48%, and 67%, respectively) and increased glutathione-S-transferase (57%, 46%, and 160%, respectively) activity. Fish exposed to MP, Gly, and Teb showed higher reduced glutathione (151%, 472%, and 130%, respectively, when compared with the control levels) and ascorbic acid concentrations (121%, 102%, and 184%, respectively),while the non-protein thiol content increased only in R. quelen exposed to tebuconazole. Fish exposed to MP and Teb showed several pathological changes in the liver, including hepatocyte degeneration and bile stagnation. The present work reports for the first time the toxicity of the pesticide MP and the fungicide Teb in R. quelen, and as in other works, suggests the relatively lower liver toxicity of Gly for fish. The data presented herein demonstrate that sublethal concentrations of MP and Teb cause changes in oxidative stress parameters as well as hepatic cell injuries in R. quelen, and that these parameters have the potential to be developed as bioindicators of exposure to these agrichemicals.