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1.
The toxicity of deltamethrin, bifenthrin, and endosulfan to the fourth-instar larvae of rice stem borer, Chilo suppressalis (Walker), was measured at 17, 27, and 37 °C. The three insecticides all displayed a positive temperature coefficient between 17 and 37 °C. The temperature coefficients of deltamethrin, bifenthrin, and endosulfan were 5.59, 1.68, and 2.85, respectively. However, temperature coefficients of deltamethrin and bifenthrin between 17 and 27 °C and between 27 and 37 °C varied. The inhibition of the above three insecticides to mitochondrial Na+-K+-ATPase and Ca2+-Mg2+-ATPase from the fourth-instar larvae of rice stem borer was determined at 17, 27, and 37 °C. The inhibition of deltamethrin to the specific activities of Na+-K+-ATPase and Ca2+-Mg2+-ATPase showed a negative temperature coefficient, but endosulfan exhibited a positive temperature coefficient. Inhibition of bifenthrin exhibited the contrary temperature coefficients between Na+-K+-ATPase and Ca2+-Mg2+-ATPase and a negative temperature coefficient for the former and a positive temperature coefficient for the later.  相似文献   

2.
The hormone profile of Sarotherodon mossambicus (Peters) under endosulfan (an organochlorine pesticide) toxicity was investigated by estimating the serum levels of T3 (triiodothyronine), T4 (thyroxine), cortisol, prolactin and insulin in control and sub-lethal (0.001 mg L−1) endosulfan-exposed fish for 1, 6, 12, 24 h and 5 days. Exposure of fish to sub-lethal concentration of endosulfan caused varying changes in the levels of serum hormones studied. Based on the results obtained, it was concluded that (i) the fish registered an increased metabolic activity during the initial period followed by an adaptive lowering of metabolic rate as indicated by changes in the serum T3 and T4 levels, (ii) the fish showed an adaptive stress response as indicated by the reduced cortisol level which could be probably due to severe interrenal exhaustion, (iii) the increased serum prolactin levels in the fish under endosulfan exposure is indicative of a possible action of prolactin on gills and kidney towards hydromineral regulation in the fish body under pesticide stress, (iv) the fish adaptively increases its serum insulin level thereby registering a possible adaptive hypoglycemic role of the hormone to favour the transport of glucose to different tissues besides a possible lipogenic activity of the higher insulin level in fish tissue under pesticide toxicity and (v) the fish appears to exhibit a possible adaptive recovery response in its hormone profile following prolonged exposure for 24 h and 5 days.  相似文献   

3.
Diazinon is commonly used for pest control in the agricultural fields surrounding freshwater reservoirs. So this study was conducted to determine the acute toxicity of this organophosphorous pesticide, contaminating aquatic ecosystems as a pollutant, and its effects on behavior, and some hematological parameters of fingerling European catfish, Silurus glanis. Diazinon was applied at concentrations of 1, 2, 4, 8, 16, 32, and 64 mg L−1. The water temperature in the experimental units was kept at 16 ± 1 °C. The number of dead fishes significantly increased in response to diazinon concentrations 2-64 mg L−1 (p < 0.05). With increasing diazinon concentrations, the fishes exposed duration 1 to 96 h significantly increased the number of dead fishes (p < 0.05 for each cases). The 1, 24, 48, 72, and 96 h LC50 values (with 95% confidence limits) of diazinon for fingerling European catfish were estimated as 14.597 (12.985-16.340), 12.487 (11.079-14.471), 8.932 (7.907-10.348), 6.326 (no data because of p > 0.05), and 4.142 (no data because of p > 0.05) mg L−1, respectively. Compared to the control specimens, fish after an acute exposure to diazinon was significantly lower erythrocyte, leukocyte, hemoglobin, hematocrit, MCV, MCH, and MCHC values (p < 0.05). In addition, it was also showed a significantly negative correlation between these hematological parameters and exposure times of diazinon (p < 0.01).  相似文献   

4.
The present study was conducted to determine the 96 h-LC50 of benomyl to the Nile tilapia, Oreochromis niloticus and to investigate the biochemical or hematological indices of blood and the alterations in the antioxidant enzymes of this fish in response to sublethal concentrations of benomyl. Fish weighing 71.61 ± 12.05 g were used in this study; they were subjected to fasting for 4 weeks before treatment. An aqueous solution of benomyl (0, 0.5, 1, 2, 4, 8, and 16 mg L−1) was administered for 96 h to determine the LC50. The 96 h-LC50 value of benomyl was 4.39 (3.23-5.60) mg L−1 in the present study. For 5 weeks, the aqueous solution of benomyl (0, 100, 200, and 400 μg L−1) was administered to investigate its effect on the hematological parameters and antioxidant enzymes. The predominant hematological findings in fish exposed to benomyl were as follows: no significant change in the Hb (g dL−1) level, MCV (μm3), MCH (pg) and MCHC (%) as compared to the control. Benomyl exposure led to greater increases in the GPT, GOT (Karmen-unit), LDH (Wroblewski unit), total cholesterol, Fe, and Ca (mg dL−1) values, whereas the levels of ALP (KA unit), total protein, triglyceride, albumin, and Mg (mg dL−1) did not increase. Benomyl increased the in vivo HSI (%), GST (nmol min−1 mg protein−1), and SOD (U mg protein−1) values in the fish livers in the test group, unlike those in the control group for 5 weeks. At concentrations higher than 100 μg L−1, benomyl affected the GST and SOD levels of Nile tilapia in a dose- and time-dependent manner. The present findings suggest that the in vivo hepatotoxicity associated with benomyl may, in part, result from the hematological index, and antioxidants may provide limited protection against benomyl toxicity.  相似文献   

5.
Nile Tilapia (Oreochromis niloticus) juveniles were exposed to different concentrations of Folidol 600® in static toxicity tests. The 24, 48, 72 and 96 h LC50 values of Folidol 600® to O. niloticus were 17.82, 8.91, 4.00 and 2.70 mg L−1, respectively. The values of hematological parameters increased, and inhibition of cholinesterases activity (AChE, BChE and PChE) in plasma of fish exposed to the higher concentrations of pesticide reached 94%. Furthermore, the exposure of Tilapia to Folidol 600® caused an increase of 4%, 20% and 38.4% in oxygen consumption at 0.1, 0.5 and 1.0 mg L−1, respectively. However, exposure to 2.5, 5.0 and 10 mg L−1 caused a decrease of 33.6%, 35.2% and 42.4% in oxygen consumption relative to the control. The ammonium excretion of fish exposed to 0.0, 0.1, 0.5, 1.0, 2.5, 5.0 and 10.0 mg Folidol 600®/L was 0.12, 0.18, 0.30, 0.33, 0.37, 0.36 and 0.33 μg/g/min, i.e., 50%, 150%, 175%, 208%, 200% and 175% increase, respectively, relative to the control.  相似文献   

6.
There is a lack of laboratory-based embryonic chicken toxicity studies with the ecologically relevant low dose/s of endosulfan that utilizes a more practical approach such as the chorioallontoic membrane (CAM) injection. In this investigation, 2μg AR grade α-endosulfan/egg (40% of LD50 for embryos) was injected through the CAM in 12-day-old chicken embryos and the activities of glucose-6-phosphatase (G6Pase, EC 3.1.3.9), fructose 1,6-diphosphatase (FDPase, EC 3.1.3.11), adenosine triphosphatase (ATPase, EC 3.6.1.3) and succinic dehydrogenase (SDH, EC 1.3.99.1) and DNA and RNA content in liver and brain tissues and acetyl cholinesterase (AChE, EC 3.1.1.7) in the latter were determined at 24, 48, and 72 h post-exposure. The wet weight of the embryos did not differ between groups. Following endosulfan exposure, except increase in the hepatic ATPase activity (P < 0.01), there was a significant decrease in the following parameters: G6Pase activity in both the liver and brain (P < 0.01), SDH activity in the brain (P < 0.01), brain overall DNA and RNA concentration (P < 0.05), brain AChE activity (P < 0.01). Exposure of 18-day-old embryos to 2-μg endosulfan for 24 h caused decrease (P < 0.01) in the lymphocyte count and IgG content. Histopathology of thymus and bursa of Fabricius revealed a reduction in the population of thymic follicles, smaller thymocytes with the clear vacuoles in cytoplasm and fewer bursocytes accompanied by infiltration of erythrocytes in lymphoid follicles of the endosulfan-treated embryos. It was inferred that in ovo injection of 0.041 μg/g egg weight of α-endosulfan suppress gluconeogenesis (main energy source in embryonic life), nerve transmission, and immunity.  相似文献   

7.
A sixty-day experiment was carried out to study the effect of dietary pyridoxine (PN) on growth performance, RNA/DNA ratio and some biochemical parameters of Labeo rohita fingerlings exposed to sub-lethal dose of endosulfan (1/10th of 96 h static non-renewal LC50 = 0.2 ppb) to assess the role of pyridoxine in ameliorating the negative effects of endosulfan. Two hundred seventy fingerlings (6.5 ± 0.26 g) were randomly distributed into six treatments in triplicates (15 fish/tank). Five iso-nitrogenous (35.45-35.75% crude protein) purified diets were prepared with graded levels of pyridoxine. Six treatment groups were T0 (10 mg PN + without endosulfan), T1 (0 mg PN + endosulfan), T2 (10 mg PN + endosulfan), T3 (50 mg PN + endosulfan), T4 (100 mg PN + endosulfan) and T5 (200 mg PN + endosulfan). Weight gain (%), specific growth rate (SGR), tissue glycogen, and protease activity were significantly (P < 0.05) higher in pyridoxine fed groups compared to their non-pyridoxine fed counterpart. Protease activity was positively correlated (R2 = 0.931) with (%) weight gain. Glucose-6-phosphate dehydrogenase (G6PDH) activity was significantly (P < 0.05) higher in non-pyridoxine fed group and decreased in pyridoxine fed counterparts. There were no significant (P > 0.05) effect of dietary pyridoxine on feed conversion ratio (FCR), protein efficiency ratio (PER), survival, gastro-somatic index (GSI), hepato-somatic index (HSI) and liver and muscle DNA levels of L. rohita fingerlings. RNA levels, both in liver and muscle, increased significantly (P < 0.05) in pyridoxine fed groups. A positive correlation was observed between growth and RNA levels, both in liver (R2 = 0.91) and muscle (R2 = 0.88). RNA/DNA ratio showed a third order polynomial relationship with dietary pyridoxine, both in liver (Y = −0.014x3 + 0.1613x2 − 0.5333x + 0.7933, R2 = 0.987) and muscle (Y = −0.0407x3 + 0.4763x2 − 1.6358x + 2.4667, R2 = 0.9345). The overall results obtained in present study indicated that dietary pyridoxine supplementation at 100 or 200 mg PN/kg diet ameliorates the negative effects of endosulfan and restores optimal growth of L. rohita fingerlings.  相似文献   

8.
The effects of lethal and sublethal concentrations of chlorpyrifos and endosulfan on oxygen consumption and ammonia excretion rate of the crab Trichodactylus borellianus were evaluated. Oxygen consumption and energy expenditure had significant effect in relation to exposure times. Regarding endosulfan, a significant difference in consumption among times of exposure was registered in 625 μg L−1. Moreover, at the highest concentration, energy expenditure rate was observed stabilized during 1-3 h. A significant increase in ammonia excretion was evidenced in 150 and 300 μg L−1 of chlorpyrifos. The O:N ratio showed a decrease in chlorpyrifos and in 2500 μg L−1 of endosulfan. This indicated a shift towards protein primary metabolism. An increment in the O:N ratio was observed in the lower endosulfan solutions. The relation oxygen:nitrogen showed a shift towards lipid and carbohydrate primary metabolism. This work indicated the complexity of the metabolism in the freshwater crab affected by xenobiotic elements.  相似文献   

9.
Endosulfan is an organochlorine pesticide widely used in agriculture and hence finds its way into natural water bodies, thus affecting aquatic life. The purpose of this study was to determine LC50 of endosulfan (99%; α:β ratio of 7:3) in Tilapia, Oreochromis mossambicus and study its effect on anti-oxidative enzymes (superoxide dismutase, glutathione-S-transferase and catalase), immuno-hematological profile (RBC, WBC, Hb, serum protein, albumin-A, globulin-G, A/G ratio, phygocytic activity as indicated by nitroblue tetrazolium reduction, serum cortisol and serum lipid peroxidation) and neurotransmitter acetylcholine esterase enzyme activity. The LC50 value at 96 h and 95% confidence limit for tilapia (46.78 g) was estimated as 3.6 μg/L. Activities of anti-oxidative enzymes, immuno-hematological profile, blood glucose and neurotransmitter activity was significantly influenced (P < 0.01) in dose dependent manner. This was reflected in the behavior of fish that was altered from normal during acute toxicity.  相似文献   

10.
Organophosphothionate insecticide fenitrothion is known as potential toxic pollutant contaminating aquatic ecosystems. The effects of fenitrothion were studied to determine the 96 h LC50 value on Nile tilapia (Oreochromis niloticus) and investigate histopathological responses of fish exposed to sublethal fenitrothion concentrations. Data obtained from the fenitrothion acute toxicity tests were evaluated using the Probit Analysis Statistical Method. The 96 h LC50 value and 95% confidence limit for Nile tilapia (58.70 ± 6.97 g) was estimated as 0.84 (0.68-1.15) mg/L. Behavioral changes were observed closely during the acute toxicity test. The bioassay experiments were repeated three times and static test method was used. Some fish exposed to 96 h 0.1, 0.5 mg/L fenitrothion concentrations showed histopathological alterations in the gills, liver, kidney, brain and testes. Severely deformations were observed at 0.5 mg/L fenitrothion on the gills lamella such as hyperemia, epithelial hyperplasia, fusion and telangiectasis, in the liver tissue such as cloudy swelling, hydropic degenerations and lipid infiltration. In addition hyperemia and hemorrhage observed in kidney tissue and hyperemia was determined in brain tissue.  相似文献   

11.
Rice (Oryza sativa), a relatively tolerant species, and early watergrass (Echinochloa oryzoides; EWG), a relatively susceptible species, were exposed to 14C-labeled clomazone to determine accumulation, biotransformation, and mass balance. On a total mass basis, rice absorbed more clomazone than EWG (p < 0.05), but on a nmol/g basis, there was no significant difference between the two species (p > 0.05). Rice contained more extractable 14C residues (7.7 ± 0.5 vs. 4.8 ± 0.5 nmol in rice vs. EWG, respectively; p < 0.5), but the concentration in EWG was significantly higher (4.2 ± 0.5 vs. 1.8 ± 0.1 nmol/g in EWG vs. rice, respectively; p < 0.01). More metabolized residue was measured in EWG compared to rice (84.1% vs. 67.9%; p < 0.01). Both species produced hydroxylated forms, β-d-glucoside conjugates, and several other unidentified polar metabolites, but EWG generally produced higher metabolite concentrations. The concentration of the suspected active metabolite, 5-ketoclomazone, was significantly higher in EWG vs. rice (21 ± 2 vs. 5.7 ± 0.5 pmol/g, respectively; p < 0.01). Differences in sensitivity to clomazone between rice and EWG appear to be due to differential metabolism, but in this case the more susceptible EWG qualitatively and quantitatively metabolized more clomazone than the more tolerant rice. This is consistent with the action of a metabolically activated herbicide. This metabolic difference could be exploited to develop herbicide safeners for use with clomazone.  相似文献   

12.
Deltamethrin (DM) is a pyrethroid insecticide widely used in Brazilian crops and in pest-control programs because of its low environmental persistence and toxicity. It has been shown to exert a wide range of effects on non-targeted organisms including fishes. The aim of this study to evaluate the effects of deltamethrin through the hematological and biochemical parameters using Ancistrus multispinis as animal model. First, blood of A. multispinis was collected by cardiac puncture in order to evaluate the basal values of the total cell counts, hemoglobin and hematocrit rates. A. multispinis showed low number leukocytes, red blood cells and hemoglobin compared to other species. The intoxication with DM (0.1 or 0.3 mg kg−1) induced leukocytosis and increases the number of erythrocytes and hemoglobin levels 96 h after the injection when compared to vehicle-injected animals. The injection of lipopolysaccharide (LPS) also induced a significant leukocytosis and increased the erythrocytes number 4 h after the injection. The combination of the higher dose of DM with LPS showed an additional effect in the number of leukocytes and erythrocytes. The GST and EROD activities were also evaluated in the gills and liver, respectively, 96 h after intoxication with both doses of DM. The GST activity decreased after DM intoxication in both doses while EROD activity was not significantly different. These results suggest that A. multispinis is a valuable model for ecotoxicological studies. Also, DM can affect the metabolizing system (GST) and immunologic system of A. multispinis, a condition that can be worsened in the presence of inflammation or infection.  相似文献   

13.
The toxicity and physiological (enzyme and nutritional indices) effect of Dysoxylum triterpenes 3β,24,25-trihydroxycycloartane and beddomei lactone were evaluated on the rice leaffolder Cnaphalocrocis medinalis (Guenée). The LC50 [6.66 ppm (SD = 0.31), 5.79 ppm (SD = 0.33) for 3β,24,25-DHCL and BL, respectively] and LC 90 [14.63 ppm (SD = 0.36), 13.49 ppm (SD = 0.27) for 3β,24,25-DHCL and BL, respectively] were identified by probit analysis. Fourth instars were exposed to various concentrations (1.5, 3, 6, and 12 ppm) of Dysoxylum triterpenes. Results showed that treated larvae exhibited reduced food consumption and enzyme activity. Food consumption, digestion, relative consumption rate, efficiency of conversion of ingested food, efficiency of conversion of digested food, and relative growth rate values declined significantly but the approximate digestibility of treated larvae was significantly higher as a result of treatment (in particular 6 and 12 ppm). Likewise, the gut enzymes acid phosphatases, alkaline phosphatases, and adenosine triphosphatases were significantly inhibited by the Dysoxylum triterpenes. The high biological activity of these triterpenes from Dysoxylum sp. could be used as an active principle during the preparation of botanical insecticides for insect pest like rice leaffolder.  相似文献   

14.
In the present study, 40 male Wistar albino rats were used and divided into 4 groups. The first group served as the control group; the second group was administered Saw palmetto extract at the dose of 20 mg/kg/bw; the third group was administered flumethrin at the dose of 15 mg/kg/bw; and the fourth group was administered a combination of 20 mg/kg/bw Saw palmetto extract and 15 mg/kg/bw flumethrin, for 21 days, orally. After the trial period, blood and tissue (liver, kidney and brain) samples were taken from the rats. Saw palmetto extract did not cause significant alterations in plasma and tissue malondialdehyde (MDA) levels, serum and tissue nitric oxide (NO) levels, erythrocyte and tissue superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities when compared to the controls (p > 0.05). Flumethrin led to increased plasma and tissue MDA levels, serum and tissue NO levels, tissue GSH-Px activities and decreased erythrocyte and tissue SOD and CAT activities, and erythrocyte GSH-Px activity, compared to the controls (p < 0.05). The flumethrin and Saw palmetto extract combination increased erythrocyte SOD activity and decreased brain GSH-Px activity as compared to flumethrin (p < 0.05). In conclusion, it was determined that Saw palmetto extract did not cause any negative effect on the prooxidant-antioxidant balance. While flumethrin stimulated lipid peroxidation; Saw palmetto extract at the dose of 20 mg/kg/bw did not exhibit enough antioxidant effect in rats.  相似文献   

15.
The aim of this study was to evaluate the effects of different N-acetylcysteine doses on the tolerance to fenthion-induced oxidative stress, alterations in glutathione metabolism and cholinesterase specific activities in the liver by using freshwater fish Cyprinus carpio (Cyprinidae) as a model organism. An acute toxicity study was carried out to determine 96-h median lethal concentration of fenthion for this species (2.16 mg/L) and 80% of this concentration was applied in toxicity studies. Four groups, each containing eight fish were constituted as follows: Control group, fenthion treated group, 0.5 or 400 mg/kg NAC-injected + fenthion-treated groups. Biochemical analyses were carried out spectrophotometrically. Fenthion treatment significantly decreased total glutathione and glutathione levels, glutathione/glutathione disulfide ratio together with glutathione reductase and γ-glutamylcysteine synthetase specific enzyme activities. The higher dose of N-acetylcysteine increased the toxic effects of fenthion and γ-glutamyl transpeptidase specific activity while decreasing glutathione S-transferase specific activity. However, injection of the lower dose provided a limited protection against fenthion toxicity. In all exposure groups, lipid peroxidation increased and total protein levels decreased, while protein depletion was prevented by low dose of N-acetylcysteine application. Acetylcholinesterase and butyrylcholinesterase activities were at similar levels in the liver of C. carpio. A dose-dependent inhibition was observed in butyrylcholinesterase activity by N-acetylcysteine application. The results showed that fenthion had a significant oxidative stress inducing potential through the reduction of glutathione redox capacity. The critical point for overcoming oxidative stress by N-acetylcysteine in fenthion toxicity was the selection of the dose; N-acetylcysteine exerted its toxic effects by means of oxidative stress in fish liver at the higher dose.  相似文献   

16.
The neurotoxic effects and acetylcholinesterase inhibition induced by endosulfan, and the amelioration of these effects by Vitamin C (Vit C), were studied in the brains of New Zealand white rabbits. The cerebrum and cerebellum of each rabbit was examined grossly and histopathologically, and caspase-3 activity was determined by immunohistochemical methods. Twenty-four rabbits were divided into four groups (n = 6). Rabbits in Group I (END) were given a sublethal dose of endosulfan (1 mg/kg bw) in corn oil daily by oral gavage for 6 weeks. Group II (END + C) received the same dose of endosulfan and also Vit C (20 mg/kg bw) every second day during the 6 week period. Group III (OIL + C) received oral corn oil daily and Vit C every second day for 6 weeks. Group IV (OIL) received corn oil daily by oral gavage throughout the experiment. A significant reduction in acetylcholinesterase activity was observed in the END group, which was ameliorated in the END + C group. Hyperemia and slight hemorrhages in brains and cerebellums were seen in some rabbits in the END group. There were no gross cerebral or cerebellar lesions in the other groups. Hemorrhages, degenerations and slight gliosis were the marked histopathological findings of some rabbits belonging to the END group. A positive caspase-3 reaction was more severe in the END group than in the others. An ameliorating effect of Vit C on gross, histopathological, and immunohistochemical findings was observed in the END + C group. Thus, although endosulfan could cause neurotoxic effects in rabbits, this toxicity was decreased by Vit C treatment, which increased serum acetylcholinesterase activity.  相似文献   

17.
The hemocyanin of Oncomelania hupensis (OhH) is essential for the survival of O. hupensis and may be an effective target for the development of new molluscicide. 4-(Chloroacetyl)catechol is a substrate analogue of OhH. In this study, we evaluated the toxicity of 4-(chloroacetyl)catechol to O. hupensis and Kunming mice. 4-(Chloroacetyl)catechol had strong molluscicidal activities and the molluscicidal activities was time and dose-dependent. With the increase of exposure time, the LC50 values of the 4-(chloroacetyl)catechol decreased from 6.5 mg/L (24 h) to 3.1 mg/L (72 h). The LC90 values decreased from 16.4 mg/L (24 h) to 4.9 mg/L (72 h). In the acute toxicity test of mice, no evident poisoning symptoms and no animal death were detected after 14 days’ continuous observation, which indicated that 4-(chloroacetyl)catechol was a low toxic substance for Kunming mice. These results indicated that 4-(chloroacetyl)catechol is potent molluscicides.  相似文献   

18.
Aquatic environments of the pampasic region of Argentina are severely affected by agricultural contamination due to an increase in a glyphosate tolerant transgenic variety of soybean crops. The present study is aimed to determine the effects of a commonly used Cyfluthrin commercial formulation (CCF) on growth, some physiological and biochemical parameter of four species of green algae. Significant inhibition of algal growth was observed from 0.1 mg Cyf/l. 96 h IC50 were between 0.92 and 4.85 mg Cyf/l. CCF caused algicidal effects. Photosynthesis was stimulated by 50% in Scenedesmus quadricauda cultures exposed to the lowest concentration (hormesis). Algal photosynthesis inhibition was observed at higher concentrations with IC50 values between 1.7 and 8.9 mg Cyf/l. Similar toxicity endpoints were found as a consequence of applying the traditional methodology of short-term chronic toxicity test of 96 h of exposition and the methodology developed using the Clark type photosynthetic oxygen evolution method. CAT activity was significantly increased between 23% and 33% considering the four species, at a lower concentration than those affecting algal growth and photosynthesis, indicating a potential biomarker. Taking into account that the extent of the soybean crops in the region is about fourteen million hectares, the improvement and extension of environmental tools for early detection of the action of pesticides on this essential group of organisms are discussed.  相似文献   

19.
Diethyl phthalate (DEP) enter into aquatic environment from industries manufacturing cosmetics, plastic and many commercial products and can pose potential fish and human health hazard. This experiment evaluated effects of DEP in adult male (89 g) common carp (Cyprinus carpio) by exposing them to fractions of LC50 (1/500-1/2.5) doses with every change of water for 28 days. Vitellogenin induction metabolic enzymes, somatic indices and bioaccumulation were studied on 7th, 14th, 21st and 28th day. The 96th hour LC50 of DEP in fingerlings was found to be 48 mg/L. Compared to control, except increase (P < 0.01) in alkaline phosphatase activity (EC 3.1.3.1) and liver size, there was decrease (P < 0.01) in activity of acid phosphatase (EC 3.1.3.2), aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2) and testiculosomatic index following exposure to 1, 5 and 20 ppm DEP. Significant (P < 0.01) dose dependant vitellogenin induction was observed with exposure of fish to 0.1, 1 and 5 ppm DEP. The bioaccumulation of DEP in testis, liver, brain, gills and more importantly in muscle tissues of fish increased significantly (P < 0.01) with increase of dose from 1 to 5 ppm. Significant interaction (P < 0.01) of dose and duration of exposure indicated that exposure period of a week to two was sufficient to bring about changes in quantifiable parameters studied. Fish exposed to 20 ppm DEP became lethargic and discolored during onset of the 4th week. This is the first report describing metabolic changes and vitellogenin induction following exposure of C. carpio to DEP dose that is as low as 1/500th fraction of LC50.  相似文献   

20.
Efficacy of certain fungicides and non-conventional chemicals against Aspergillus spp. contamination and subsequent aflatoxin production in rice was investigated. Among the 10 fungicides tested, carbendazim, contaf plus, folicur, propiconazole and saaf completely inhibited the growth of all Aspergillus spp. and aflatoxin B1 (AFB1) production at 1 g or ml/kg concentration. Of the five non-conventional chemicals tested, benzoic acid effectively inhibited the mycelial growth of Aspergillus flavus (72%) at 4 g/kg, completely inhibited the Aspergillus parasiticus and Aspergillus niger even at 1 g/kg and Aspergillus ochraceus at 4 g/kg concentration. Vanillin completely reduced the AFB1 production at 4 g/kg of seed followed by sodium chloride with out inhibiting the mycelial growth. This study reveals that fungicides and non-conventional chemicals had effectively inhibited the mycelial growth of Aspergillus spp. and AFB1 production in rice.  相似文献   

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