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1.
The gonads of spawning Mystus vittatus exposed for 96 h to the LC50-96 h dose (i.e. 550 ppm) of NPK, the agricultural fertilizer, were biochemically analysed for their carbohydrate content. The glucose and glycogen contents of the spawning fish were found to be lowered significantly, and the total carbohydrate and lactic acid contents altered insignificantly, under the pollutional stress. The stressed fish also exhibited the presence of some additional free sugars within their gonads.  相似文献   

2.
Exposure of Channa striatus over 24 h to 40% and 80% of the LC50;24h of the three pyrethroids cypermethrin, permethrin, and fenvalerate did not cause any significant changes in the levels of total protein and free amino acids in the liver and muscle tissues of the fish. After 96 h exposure, the protein amino acid levels are altered significantly.  相似文献   

3.
Increased hazard of arsenic toxicity at many provinces of India causing extensive contamination of their wetlands. To illustrate the consequences of the arsenic menace on the aquatic fauna, a nutritionally important freshwater catfish Clarias batrachus (Linn.) was subjected to the stress of sublethal concentration (1 mg/L; 5% of 96‐h LC50 value) of sodium meta‐arsenite. The alterations induced by the arsenic salt on certain biomolecules (proteins, free amino acids (FAA), and protease activities) in five tissue components (muscle, liver, brain skin, and gills) of the fish using biochemical techniques were estimated. Significant (p < 0.01) decrease in the concentration of proteins in all the tissues (19.74–44.84% in muscles; 3.17–49.39% in liver; 10.05–36.16% in brain; 12.62–52.01% in skin and 7.34–61.69% in gills), and significant (p < 0.01) increase in FAA (6.84–269.89% in muscles; 125.89–358.03% in liver; 1.07–152.90% in brain; 29.31–401.62% in skin and 38.53–165.07% in gills), and protease activities (43.59–183.33% in muscles; 19.52–131.90% in liver; 8.85–46.72% in brain; 33.33–261.53% in skin and 25.39–50.79% in gills) of the exposed fish were observed. This increase in amino acids and enzyme activity point out toward breakdown of protein leading to their depletion.  相似文献   

4.
The haematological, biochemical, and enzymological alterations produced on exposure of Channa punctatus to LC50 (11.2 mg/L) for 96 h and to a sublethal concentration (1.12 mg/L) of cadmium (Cd2+) for 15, 30, 60, and 120 days have been studied. The fish were hypoglycemic and hypolactemic. The pyruvate content of blood and liver decreased in acute and all stages of chronic exposure except for 30 days where significant increase was recorded. Depletion was noted in the total protein and glycogen content of liver and muscle, and the level of lactate in liver in the two types of exposure. The levels of muscle lactate and pyruvate increased in both exposures. The activities of hexokinase, glucose-6-phosphatase, and lactate dehydrogenase decreased in liver after 96 h and all stages of chronic exposure except 30 days. The activities of hexokinase and lactate dehydrogenase in muscle and glutamate-oxalacetate transaminase and glutamate-pyruvate transaminase in serum, liver, and muscles increased in all exposures. The activities of succinate and malate dehydrogenases in liver and muscles decreased after acute and all stages of chronic exposure. The above results suggest that glycolysis and gluconeogenesis were impaired in liver but glycolysis prevailed in muscle. Aerobic oxidation is adversely affected in metal exposed fish, while proteolysis was increased.  相似文献   

5.
Specimens of either sex of the freshwater catfish Mystus vittatus were exposed to an acute toxic dose of an agro-chemical NPK, i.e. 550 ppm during the spawning phase of their annual reproductive cycle. The effects on total lipid and its various fractions, viz. phospholipids and cholesterol, were studied in the testes and ovary. The total lipid content of the gonads of unstressed fish showed lowest values during the spawning phase when compared to other phases, the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning period, the fall in total lipid content of the gonads was found to be much greater than that in the controls. The phospholipids content of the gonads of unstressed fish showed highest values during the spawning phase when compared to other phases; the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning phase the rise in the gonads was found to be higher than that in the control. The cholesterol content of the gonads of unstressed fish showed highest values during the spawning phase when compared to other phases; the content remained higher in the ovary than in the testes. In fish subjected to NPK-stress during the spawning period the rise in the cholesterol content of the gonads was not found to be as high as that in the controls. Agro-chemical NPK seemed to effect the total lipid and cholesterol content adversely during the spawning phase, affecting the vitellogenic process without affecting the biosynthesis of phospholipids as such, which on the contrary increases. The decrease of lipid and cholesterol mobilization from liver to gonads seemed to be restricted as a result of NPK action.  相似文献   

6.
The most recent findings in tilapia's nutritional physiology have been critically reviewed bearing in mind the future of this species in world aquaculture. This fish requires ten essential amino acids and a high protein content in the diet to achieve a maximum growth. The utilization of animal and vegetable protein may differ between the species of tilapias but generally fish growth was decreased while being offered plants or processed corn meals in comparison to diets with animal ingredients. Some problems connected with the nutrition terminology and new areas of research on Tilapia were discussed.  相似文献   

7.
The tolerance level of the fertilizer NPK for the freshwater siluroid Mystus M. vittatus (BL .) and histopathological changes in the gill of this fish against two concentrations of NPK were investigated. It was found that at 400 ppm (24 h) mortality in the fish started, and at 700 ppm (96 h) all the fish died. Hence the concentration of NPK at 400 ppm was taken as an experimental concentration for this fish. Curling towards the upperside in the secondary lamellae resulting in the joining with each other and profuse mucus secretion and subsequent death of 40% of the fish (96 h) were observed. At 700 ppm (96 h) NPK, which is far higher than the highest tolerance limit of the fish, all the fish died. Profuse mucus secretion, formation of subepithelial spaces, sloughing of epithelial layer, leaving only the rows of pilaster cells, resulting in the death of the fish, were observed. The mortality of the fish was due to asphyxiation and damage in the gill tissues resulting in the alteration in the respiratory and osmoregulatory metabolism.  相似文献   

8.
Static bioassay tests were carried out on Channa punctatus Bloch in the laboratory after renewal of concentrations every 24 h. The LC50 values and 95 per cent confidence limits were 45.21 (39.62 … 51.11) ppm at 12 h and 29.8 (27.49 … 31.95) ppm of Zn at 96 h of exposure. The actual dissolution values of zinc were also determined in test solutions using an atomic absorption spectrophotometer. Behavioural changes were the higher rate of opercular movements, surfacing, loss of equilibrium and haemorrhage near mouth and caudal fin. The LT50 values indicate that survival was increased with decreasing Zn concentration. The histopathological changes observed due to Zn toxicity in the gills have been discussed in relation to fish mortality.  相似文献   

9.
The effects of exposure to LC50 (10.5 mg/l) for 96 h and to a sublethal concentration (1.05 mg/l) of Sevin for 120 days have been observed on some haematological, biochemical and enzymatic parameters of Channa punctatus. The fish were hyperglycemic and hyperlactemic and the glycogen content of the liver and muscles decreased, but the lactic acid content of two tissues increased. The activity of hexokinase increased in the kidney, intestine, liver and muscles but decreased in the gills and brain. The activity of lactate dehydrogenase decreased in the kidney and intestine, and increased in the liver, muscles, brain and gills. The pyruvate dehydrogenase activity decreased in all the six tissues. Both the exposures produced a decrease in the succinate dehydrogenase activity of the liver. The enzyme activity decreased in the brain, gills and muscles after chronic exposure, whereas the kidney and intestine showed an elevation in enzyme activity.  相似文献   

10.
Exposure against two ppm chromium from K2Cr2O7 for 1 to 7 months produced increasing accumulation of chromium in the liver, kidneys, brain and bone of the freshwater fish Mystus vittatus. In gonads, the accumulation of chromium was progressive for the first 5 months (i.e., April to August), but not in the subsequent 2 months. After 4 months exposure, fish transferred to chromium–free freshwater had a significant depletion of chromium from all tissues at 1, 2 and 3 months.  相似文献   

11.
Heike Koppitz   《Limnologica》2004,34(1-2):37
Changes in the contents and composition of dissolved amino acids and carbohydrates were monitored in different Phragmites australis stands in Germany. Four different reed clones planted in 1997 in a degraded fen area in NE-Germany were compared with respect to the seasonal development in the total amount of amino acids and sugars in the basal culm internodes. The individual Phragmites clones showed significant differences in the absolute content of both parameters indicating an influence of the genotype. Flooding affected the ratio of amino acids to carbohydrates within the reed clones. Plants grown in flooded parts of the fen area revealed a significantly higher total amino acid content together with a lower total content of carbohydrates.Furthermore, the effects of extreme flooding on the content and composition of amino acids and carbohydrates in the basal culm internodes of Phragmites australis were studied in nine reed stands with different degrees of damage on Lake Constance. Shoots from extremely damaged reed stands were characterised by a significant decrease in the total content of carbohydrates, an increase in the total content of amino acids and an increase in the share of γ-aminobutyric acid. These changes in the content and composition of carbohydrates and amino acids were discussed with respect to their value as stress indicators, such as for oxygen deprivation which causes a hypoxic metabolic state in Phragmites australis stands.  相似文献   

12.
The toxicity of phenol, pentachlorophenol and Na-pentachlorophenate to Cypris subglobosa is determined in the batch experiment for 96. h. In the sequence mentioned, the LC50,96h of the three substances are 71.8, 6.56 and 4.41 mg/l, respectively. In the range of 6 … 95 h the mean survival time shows a negative regression to the toxicant concentration, which, however, is not significant statistically for Na-pentachlorophenate. In agreement with this, the LC50 for 12, 24, 48, 72 and 96 h of exposure shows a significant decrease. Due to the comparatively high LC50,96h for pentachlorophenol and Na-pentachlorophenate for C. subglobosa about in comparison with fish, the species is little suited to the toxicological investigation of wastewater.  相似文献   

13.
Effects of acute cadmium poisoning on survival, its residual values and histopathology in certain organs of a freshwater airbreathing fish, Channa punctatus (BLOCH ) were investigated. The threshold concentration, MATC and LC50 values obtained from 96 h static bioassay, revealed that Channa is more susceptible to cadmium ions at higher temperature. The atomic absorption spectrophotometric determination of cadmium residues differed significantly in organs of specimens having survived and died after 96 h of exposure. The gill accumulate the highest amount of cadmium, the liver accumulated a slightly smaller amount than the gill, while the kidney accumulated the least. The histopathological lesions subjected to sublethal (5.2 mg/l Cd) and lethal (8.4 mg/l Cd) concentrations of cadmium were: detachment and rupture of lamellar epithelium, collapse of pillar cells and hypertrophy in mucus producing gland cells in the gill; vacuolization and coagulative necrosis in hepatic cells of the liver; and expansion, necrosis and accumulation of cellular debris in renal tubules of the kidney. The probable causes for death of fish due to cadmium ions have been discussed.  相似文献   

14.
The free amino acids of the liver and muscle of C. punctatus exposed to 1 ppm of copper sulphate solution up to 84 days were investigated. Few amino acids, notably cystine and tryptophan, disappeared and few new amino acids appeared. These changes in the free amino acids may be due to toxic effects of copper sulphate leading to rancidity in the fish.  相似文献   

15.
It depends on the trophic position of a species whether its growth is limited by the quantity or quality of diet: predators are frequently limited by the quantity of diet, primary consumers frequently by the quality of diet. The protein deficiency is of decisive importance for the growth of primary consumers. The digestible protein/digestible energy ratio is most important: 4 mg/kJ are sufficient for maintenance, 20… 30 mg/kJ are necessary for maximum growth. These values can be confirmed by feeding tests with Carassius auratus. According to measurements by different methods, the organic nitrogen is present in the detritus in the form of amino acids as bonded to organis matter. Thus, Sarotherodon mossambicus assimilates 25.6 mg amino acids/kJ from detritus, whereas only 25% of these amino acids can be identified as protein. Due to the utilization of this source of diet, detrivorous fish occupy a special position in the chain of diet, thus gaining a great importance for the aquatic culture.  相似文献   

16.
Static bioassays were conducted at 20.5£C and the hardness of 260 ppm as CaCO3 with zinc sulphate and nickel sulphate using Puntius sophore, Rasbora daniconius neilgeriensis, Channa punctatus and Lebistes reticulates. The 96 h LC50 values for all four fish species ranged from 29.88 to 54.95 £ of zinc and 13.57 to 48.83 £ of nickel. Channa punctatus were consistently more sensitive to zinc, while Puntius sophore were to nickel. The behavioural changes, such as loss of equilibrium and shoaling nature, swimming with their bellies upwards and irregular opercular movement were noted.  相似文献   

17.
The 96h LC50 of the water soluble fraction (WSF) of natural gas condensate from the Sable Is., N.S. area to Fundulus heteroclitus was between 4 and 5 μg · ml−1 naphthalene equivalents (initial concentration). Behavioural responses in the fish to sub-lethal concentrations of WSF were similar to those recorded for crude and fuel oils. Induction of the hepatic mixed function oxidase enzyme enthoxyresorufin O-de-ethylase (EROD) in sexually immature fish occurred at WSF concentrations below the LC50, but during the prespawning period no induction occurred. EROD activity in unexposed fish showed seasonal variation consistent with differences in its inducibility.  相似文献   

18.
Monocrotophos (0,0-dimethyl-0-(1-methyl-2-N-methyl-carbamoyl)-cis-vinylphosphate) as an active component of some insecticides is highly soluble in water at a low hydrolysis rate: half-time at 2 mg/l, pH = 7.0 and 38 °C 23 d. Individuals of the following fish species (individual weight in g) were kept during the static bioassay for 6… 72 h at 40 mg/l monocrotophos in the medium: Cyprinus carpio (70), Carassius carassius (45) and Leucaspius delineatus (1.5), and then the concentration of monocrotophos was gas-chromatographically determined in different tissues. Initially, till the 24th hour a high accumulation in the gills took place (in mg/kg fresh weight: Cyprinus 0.49, Carassius 3.88), then the concentration remained uniform or slightly falling here, whereas in the other organs (digestive organs, muscle, gonads) a further accumulation up to 1 mg/kg occurred. Leucaspius was investigated only as whole individuals, and after 72 h their fresh weight had increased to 6.96 mg/kg. The rates of accumulation decrease in the following order: Cyprinus: digestive organs, gills, muscle; Carassius: gills, digestive organs, gonads, muscle.  相似文献   

19.
The present paper deals with the evaluation of the relative resistance of 12 species of fish in static toxicity bioassay tests of electroplating waste. The electroplating waste is highly toxic as it contains several toxic metals like copper, nickel, cadmium, zinc, lead and chromium alongwith cyanides, acids and alkalies. On the basis of TL50, the fish Clarias batrachus ist the most resistant fish and Labeo rohita the most sensitive. The relative resistance of the fish is in the decreasing order: Clarias batrachus, Saccobranchus fossilis, Ophiocephalus gachua, Ophiocephalus punctatus, Puntius stigma, Puntius sophore, Mystus vittatus, Cyprinus carpio, Colisa fasciatus, Notopterus notopterus, Cirrhina mrigala and Labeo rohita.  相似文献   

20.
When mollusc shells are analysed conventionally for amino acid geochronology, the entire population of amino acids is included, both inter- and intra-crystalline. This study investigates the utility of removing the amino acids that are most susceptible to environmental effects by isolating the fraction of amino acids encapsulated within mineral crystals of mollusc shells (intra-crystalline fraction). Bleaching, heating and leaching (diffusive loss) experiments were undertaken on modern and fossil Corbicula fluminalis, Margaritifera falcata, Bithynia tentaculata and Valvata piscinalis shells. Exposure of powdered mollusc shells to concentrated NaOCl for 48 h effectively reduced the amino acid content of the four taxa to a residual level, assumed to represent the intra-crystalline fraction. When heated in water at 140 °C for 24 h, only 1% of amino acids were leached from the intra-crystalline fraction of modern shells compared with 40% from whole shell. Free amino acids were more effectively retained in the intra-crystalline fraction, comprising 55% (compared with 18%) of the whole shell after 24 h at 140 °C. For fossil gastropods, the inter-shell variability in D/L values for the intra-crystalline fraction of a single-age population was reduced by 50% compared with conventionally analysed shells. In contrast, analysis of the intra-crystalline fraction of C. fluminalis does not appear to improve the results for this taxon, possibly due to variability in shell ultrastructure. Nonetheless, the intra-crystalline fraction in gastropods approximates a closed system of amino acids and appears to provide a superior subset of amino acids for geochronological applications.  相似文献   

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