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1.
After feeding Atlantic salmon, Salmo salar L., five graded amounts of wheat starch from 0 to 310 g kg?1, low but increased levels of glycogen in kidney, heart and gills were determined. No variations were found in proximate or glycogen compositions of muscle, whereas the liver composition reflected the diet composition. Whole-body homogenates varied in dry matter and lipid levels; the variation was according to g lipid eaten per fish. Plasma glucose levels ranged above average levels only when the starch level in the feed was higher than 220 g kg?1. Although feed intake and thereby lipid intake increased as dietary carbohydrate increased in the present experiment, no differences in plasma concentrations of cholesterol and only small changes in triglycerides were determined. The increase in dietary carbohydrate was balanced with protein, and total plasma protein concentrations followed the decrease in feed protein content. Haematocrit, haemoglobin, mean cell volume and mean cell haemoglobin all showed significantly reduced levels as dietary starch increased, indicating a fibre effect from ‘left-over’ starch in the intestine followed by reduced absorption of divalent ions, such as iron.  相似文献   

2.
This publication reports on analytical data from a large-scale experiment, using 3360 Atlantic salmon, Salmo salar L., distributed into 12 sea cages. Salmon were grown from an average 600 g to an average 3.5 kg. Samples for analyses were taken when fish were in the range of 1.8 and 3.5 kg. Dietary changes between groups were increased starch from 24 to 230 g kg?1 and balanced with protein. The diets were isolipic. All salmon showed small stores of glycogen in all analysed organs, and only in heart, gills and kidney of large fish (3.5 kg) were the levels correlated with dietary starch. Minor differences between groups were found in liver NADPH production, but with substantially decreased NADPH production per g protein as the fish grew from 1.8 to 3.5 kg, indicating that increasing dietary starch did not lead to induction of liver hexokinase, and that the activity of this enzyme may decline as fish size increases. An increase in plasma glucose concentrations was found as dietary starch increased, but all levels were moderate and ranged within reference values. Plasma total protein concentrations did not, however, vary according to decreased dietary protein, but increased substantially in all groups as the fish grew from 1.8 to 3.5 kg. Dietary treatments had no influence on haematological parameters, except for decreased haemoglobin concentrations as dietary starch increased in large fish (3.5 kg). No impared liver function was detected, evaluated by activities of ASAT, ALAT and LDH, and by histological analyses. Low serum lysozyme activities were recorded in all groups, and were not correlated with plasma glucose or liver glycogen concentrations.  相似文献   

3.
In the present study cod were separately placed in fish metabolic chambers. Ten individuals were injected with a dose of 1 μCi 14C-glucose, in addition to 1 g pure glucose per kg live weight, and 10 individuals were kept under the same conditions and sham injected with 9 g L−1 (0.9%) sterile saline solution.
Of the injected 14C-glucose, 3% was recovered in plasma, 2.9% in liver, 1.7% in red muscle, 18.2% in white muscle, 0.2% in heart, 1.9% in gills and 12.1% in gill-surrounding water. Of the 12.1% in gill-surrounding water, 9.1% was found to be in the form of CO2, leaving 3% to pure glucose and lactate. These results indicate a relatively high production of CO2 from glucose showing a utilization for energy, and a possible route of excretion of excess glucose via the gill membrane.
Activity of 14C-glucose on a concentration basis showed in descending order the following organs to be metabolically active in glucose utilization: gills > plasma (as a transporter) > heart > red muscle > liver > white muscle.
Of the total amount of 14C-glucose injected, only 0.3% was recovered in the liver lipid fraction, and mainly as triacylglyceroles; minor 14C-activity was found in mono- and diacylglyceroles and free fatty acids. These results show very low activity of de novo syntheses of lipid from injected glucose in the cod.  相似文献   

4.
Accumulation of 14C in various tissues and organs was studied in three different groups of 0.8‐kg Atlantic salmon Salmo salar force‐fed with 14C1‐glucose in order to evaluate if metabolism of glucose depended on adaptation to dietary carbohydrate level. The salmon had been fed diets supplemented with 0, 100 and 200 g maize dextrin kg?1 for 10 months before the experiment. The fish were force‐fed 6.65 × 104 Bq of 14C1 glucose kg?1 BW, in gelatin capsules. Fish for analysis were obtained 16 h later. 14C was measured in blood plasma, gill, kidney, liver and white muscle, and in lipid extract of liver. The liver contained most 14C, followed by heart, blood plasma, gill and liver lipid extract, while kidney and muscle contained the least 14C per gram or millilitre tissue. The muscle contained most radioactivity, on an estimated total tissue basis, followed by liver, blood plasma, gill, liver lipid extract, kidney and heart tissue. Thirty‐eight per cent of the orally administered 14C was recovered in the salmon adapted to the diet without dextrin after 16 h. This was significantly (P < 0.05) higher than the 30% and 32% recovered in the salmon adapted to diets with 10% and 20% dextrin. This effect on adaptation to dietary dextrin level in glucose uptake or metabolism was supported by a trend (P < 0.10) toward higher radioactivity per gram or millilitre of each individual tissue in the fish adapted to the diet without dextrin, when compared with the other two adaptation regimes.  相似文献   

5.
Abstract The ability of silver perch ( Bidyanus bidyanus ) to digest and utilize dietary starch or starch breakdown products was investigated. For experiment 1 the ability of silver perch (2.7 ± 0.01 g) to digest wheat starch at two dietary inclusion levels (30% or 60%), each at four levels of gelatinization (0%, 25%, 50% or 80%), was investigated over a 31-day period. For experiment 2, the ability of silver perch (15.9± 0.25 g) to digest wheat starch, dextrin (at three levels of dextrinization), maltose, glucose and pea starch, all at the 30% inclusion level, was investigated over a 41-day period. Water temperature for both experiments was 25 ± 1 °C. Apparent digestibility coefficients (ADCs) for starch, dry matter (DM) and energy were affected by both degree of gelatinization (80% > 50% > 25% = 0%) and inclusion level (30% > 60%). Specific growth rate (SGR) was unaffected by the inclusion of 30% starch; however, it was reduced at the 60% starch content level. Degree of gelatinization had no effect on SGR. For experiment 2, there were significant differences between carbohydrate and DM ADCs for the test ingredients. The carbohydrate, DM and energy ADCs were ranked as follows: dextrin (Fieldose 9) = dextrin (Fieldose 17) = dextrin (Fieldose 30) = gelatinized wheat starch = maltose = glucose > raw wheat starch > raw pea starch. The protein ADC of the diets, postprandial plasma glucose concentration and SGR were all unaffected by ingredient type. For both experiments, HSI tended to increase with carbohydrate inclusion. Liver glycogen concentrations were also elevated, but muscle glycogen and liver and muscle triacylglycerol concentrations were unaffected. Digestibility of starch by silver perch is clearly affected by inclusion content and processing.  相似文献   

6.
Τhe uptake and distribution of lipopolysaccharide (LPS), isolated from Aeromonas salmonicida, was investigated in Atlantic cod, Gadus morhua L., turbot, Scophthalmus maximus L., and Atlantic halibut, Hippoglossus hippoglossus L. LPS was radiolabelled by bromine oxidation and subsequent sodium borotritide reduction (3H-LPS), and fluorescence-labelled by introducing a fluorescein isothiocyanate derivative (FITC-LPS). After intravenous and intraperitoneal injections in cod, high amounts of radioactive LPS (3H-LPS) were present in heart, spleen and kidney throughout the experimental period (1–168 h). After peroral administration, a high amount of 3H-LPS was observed in intestinal tissues, whereas internal organs and tissues contained considerably lower amounts. Following intravenous administration of 3H-LPS in turbot, high contents of radioactivity were revealed in spleen, liver and kidney, whereas the content in heart was lower than in blood at the sampling times (1–24 h). The same pattern was observed after intraperitoneal administration. The spleen and liver contained high amounts of radioactivity when the turbots were intubated perorally with 3H-LPS. The spleen, kidney and heart were the main scavenging organs following intravenous administration of 3H-LPS in Atlantic halibut. A minor amount of radioactivity was present in the liver. The same pattern emerged after intraperitoneal injection in halibut. As observed for turbot, the spleen was the main accumulation site for 3H-LPS following peroral administration. Fluorescence microscopy of sections of organs and tissues from cod, intravenously and intraperitoneally injected with FITC-LPS, revealed that endocardial cells of both atrium and ventricle contained large amounts of the fluorochrome, whereas in turbot and halibut only atrial endothelial cells accumulated the substance. In all species, macrophages in kidney and spleen contained FITC-LPS and in the spleen the fluorochrome was trapped in the ellipsoidal walls. At later time points (e.g. 48 h) in the turbot spleen, FITC-LPS was located in cells adjacent to the ellipsoidal walls. Halibut endothelial cells that were located in the connective tissue of the intestine and gills also contained FITC-LPS. After peroral administration to the different fish species, specific fluorescence was found only in intestinal epithelial cells of halibut and in cells located in the lamina propria. Fluorescence was not detected in internal organs such as the kidney, spleen and liver after peroral administration of FITC-LPS. Gel chromatographic analysis of plasma samples from cod, turbot and halibut after intravenous and intraperitoneal injections showed that high molecular weight radioactivity was present. A minor amount of radioactivity that corresponded to low molecular weight substances was also observed. In conclusion, there is a high degree of variation with respect to the site of accumulation and some variation in the type of cells involved in the uptake of purified LPS in cod, turbot and halibut.  相似文献   

7.
The present study evaluated how different photoperiods, carbohydrate sources and inclusion levels influenced growth, plasma, organ and body compositions in Atlantic salmon (Salmo salar). Four different diets were used, containing 10 or 20% starch on a dry matter basis, using gelatinized corn (C10 and C20) or wheat (W10 and W20). Two different photoperiods were used, Continuous (Con) light throughout the study, Winter (Wi) two initial weeks of continuous light, thereafter 6 weeks of short day, ending with 6 weeks of continuous light. The winter regime resulted in reduced growth rate compared with continuous light. All Wi groups were smaller than Con groups when the experiment was terminated, except for fish given diet C10. Diet W10 resulted in better growth compared with all other groups when exposed to Con. regime. Atlantic salmon fed with diets containing 20% starch had lower growth rates than fish fed diets containing 10% starch, when the same starch source and light regime were compared. All fish belonging to the Con group exhibited similar and higher condition factors compared with fish from groups Wi. Condition factor was not influenced by dietary starch source. Higher whole body lipid concentrations were found when fish were given the corn compared with the wheat diets, without any responses to starch level or light regime. Whole body protein showed increased values in fish exposed to regime Wi compared with Con, without any influence from dietary manipulation. Liver glycogen values and hepatosomatic index reflected dietary starch levels and were significantly influenced by light regime, whilst muscle glycogen levels varied only as a response to light regime with lower values in fish from the Wi compared with the Con groups. Light regime influenced plasma glucose levels, except in groups fed with diet W10. All measured plasma nutrient concentrations were within normal ranges. At the end of the feeding period, all fish were evaluated for glucose and salt water tolerance to ascertain whether diet and/or light regime influenced glucose regulation capacity and/or smolt quality. Fish fed with 20% starch had reduced osmoregulatory ability measured as plasma chloride after a seawater challenge test. Fish from the Wi regime, but not from the Con regime developed characteristics associated with smoltification. Glucose tolerance in Atlantic salmon was substantially influenced by both photoperiod regime and diet. Fish reared under the Wi photoperiod showed reduced glucose regulation capacity compared with fish held under continuous light. Glucose regulation capacity was also reduced in fish adapted to the highest starch levels.  相似文献   

8.
This experiment was conducted to study the effects of dietary carbohydrate on glucose metabolism in gibel carp (Carassius gibelio) as well to investigate if different clones had different responses to carbohydrate intake. Unselected Dongting strain (DT strain), selected gibel carp “CAS III” (A strain) and gibel carp “CAS V” (F strain) were fed with no corn starch diet (0C), 30% corn starch diet (30C) and 45% corn starch diet (45C) for 8 weeks. The results showed that selected F strain showed higher growth performance. F strain and A strain showed better control on postprandial glucose regulation by increasing plasma triglyceride, plasma cholesterol, liver and muscle glycogen contents and also enhancing glycolysis and restraining gluconeogenesis. DT strain had higher body lipid and lipid utilization. In conclusion, gibel carp could tolerate 45% dietary carbohydrate and F strain showed better growth by increasing glycolysis while decreasing glycogenesis.  相似文献   

9.
为探讨在低蛋白水平(40%)下,饲料中不同种类的碳水化合物(葡萄糖、蔗糖和糊精)对大菱鲆幼鱼[(8.12±0.04)g]生长、成活、饲料利用、体组成和血液生理生化指标等的影响,实验在对照组饲料中未添加可消化碳水化合物,含40%的蛋白质和18%的脂肪,然后在对照组饲料的基础上,调节脂肪水平为12%,分别添加15%的葡萄糖、蔗糖和糊精配制3组实验饲料。在流水式养殖系统中进行9周的大菱鲆生长实验。结果显示,各处理组大菱鲆成活率均高于95.24%,并且各组间无显著差异;对照组和糊精组大菱鲆的增重率(WGR)和特定生长率(SGR)均显著高于葡萄糖组和蔗糖组。各组间的日摄食率(DFI)没有显著差异。对照组和糊精组饲料效率(FE)显著高于蔗糖组,但葡萄糖组FE与其它各组无显著差异;各处理组间蛋白质和脂肪表观消化率(ADC)未受碳水化合物种类的显著影响,而可消化碳水化合物的ADC依次为:葡萄糖组>糊精组>蔗糖组(。葡萄糖组的能量ADC最高,蔗糖组的最低;除对照组肌肉脂肪含量显著高于其它各组外,碳水化合物的种类对大菱鲆肌肉常规组成及糖原含量无显著影响,但显著影响了肝脏的脂肪和糖原含量。大菱鲆肝脏脂肪含量依次为对照组>糊精组>蔗糖组>葡萄糖组,肝脏糖原含量依次为葡萄糖组>蔗糖组>糊精组>对照组;不同碳水化合物种类对大菱鲆幼鱼血浆葡萄糖含量没有显著影响,但显著影响血浆总氨基酸、胰岛素、总胆固醇(CHO)和甘油三酯(TAGs)的含量。结果表明,本实验条件下,大菱鲆对糊精的利用效率优于葡萄糖和蔗糖,并且不同种类的碳水化合物通过糖脂关联代谢等途径对大菱鲆幼鱼的体组成和血液生理生化指标造成一定的影响。  相似文献   

10.
The effect of dietary amylose/amylopectin (AM/AP) ratio on growth, feed utilization, digestive enzyme activities, plasma parameters, and postprandial blood glucose responses was evaluated in juvenile obscure puffer, Takifugu obscurus. Five isonitrogenous (430 g kg?1 crude protein) and isolipidic (90 g kg?1 crude lipid) diets containing an equal starch level (250 g kg?1 starch) with different AM/AP ratio diets of 0/25, 3/22, 6/19, 9/16 and 12/13 were formulated. Each experimental diet was fed to triplicate groups (25 fish per tank), twice daily during a period of 60 days. After the growth trial, a postprandial blood response test was carried out. Fish fed diet 6/19 showed best growth, feed efficiency and protein efficiency ratio. Hepatosomatic index, plasma total cholesterol concentration, liver glycogen and lipid content, and gluconokinase, pyruvate kinase and fructose-1,6-bisphosphatase activities were lower in fish fed highest AM/AP diet (12/13) than in fish fed the low-amylose diets. Activities of liver and intestinal trypsin in fish fed diet 3/22 and diet 6/19 were higher than in fish fed diet 9/16 and diet 12/13. Activities of liver and intestinal amylase and intestinal lipase, and starch digestibility were negatively correlated with dietary AM/AP ratio. Fish fed diet 3/22 and diet 6/19 showed higher plasma total amino acid concentration than fish fed the other diets, while plasma urea nitrogen concentration and activities of alanine aminotransferase and aspartate aminotransferase showed the opposite trend. Equal values were found for viscerosomatic index and condition factor, whole body and muscle composition, plasma high-density and low-density lipoprotein cholesterol concentrations, and activities of lipase and hexokinase and glucose-6-phosphatase in liver. Postprandial plasma glucose and triglyceride peak value of fish fed diet 12/13 were lower than in fish fed the low-amylose diets, and the peak time of plasma glucose was later than in fish fed the other diets. Plasma glucose and triglyceride concentrations showed a significant difference at 2 and 4 h after a meal and varied between dietary treatments. According to regression analysis of weight gain against dietary AM/AP ratio, the optimum dietary AM/AP ratio for maximum growth of obscure puffer was 0.25. The present result indicates that dietary AM/AP ratio could affect growth performance and feed utilization, some plasma parameters, digestive enzyme as well as hepatic glucose metabolic enzyme activities in juvenile obscure puffer.  相似文献   

11.
王猛强  黄文文  周飘苹  金敏  邱红  周歧存 《水产学报》2015,39(11):1690-1701
本实验旨在研究不同蛋白质和小麦淀粉水平对大黄鱼生长性能、肝脏糖酵解和糖异生关键酶活性、血清指标、糖原含量及消化酶活性的影响。采用2×3双因素实验设计,共配制6组饲料,包含2个蛋白质水平(41%、46%)和3个小麦淀粉水平(10%、20%、30%),选取初重约为(14.84±0.16) g的大黄鱼900尾,随机分为6组(每组3个重复,每个重复50尾),进行8周的养殖实验。实验结果表明:饲料蛋白质和小麦淀粉水平的交互作用对大黄鱼增重率和特定生长率无显著影响(P>0.05),且在相同的饲料蛋白质水平下,饲料小麦淀粉水平对大黄鱼增重率和特定生长率无显著影响(P>0.05)。饲料蛋白质和小麦淀粉的交互作用对大黄鱼肝脏6-磷酸果糖激酶(phosphofructokinase,PFK)、丙酮酸激酶(pyruvate kinase,PK)、果糖-1,6-二磷酸酶(fructose-1,6-bisphosphatase,FBPase)活性有显著影响(P<0.05),但对葡萄糖激酶(glucokinase,GK)、葡萄糖-6-磷酸酶(glucose-6-phosphatase,G6Pase)、磷酸烯醇式丙酮酸羧激酶(phosphoenolpyruvate,PEPCK)活性无显著影响(P>0.05)。当饲料蛋白质水平为41%时,饲料小麦淀粉水平对葡萄糖激酶、6-磷酸果糖激酶和果糖-1,6-二磷酸酶活性有显著影响(P<0.05),且果糖-1,6-二磷酸酶活性随着饲料小麦淀粉水平的升高呈下降趋势,但对丙酮酸激酶、葡萄糖-6-磷酸酶、磷酸烯醇式丙酮酸羧激酶活性无显著影响(P>0.05);当饲料蛋白质水平为46%时,饲料小麦淀粉水平对葡萄糖激酶、6-磷酸果糖激酶、丙酮酸激酶、果糖-1,6-二磷酸酶活性有显著影响(P<0.05),且葡萄糖激酶、6-磷酸果糖激酶、丙酮酸激酶均随饲料小麦淀粉水平的升高呈上升趋势,但对葡萄糖-6-磷酸酶和磷酸烯醇式丙酮酸羧激酶活性无显著影响(P>0.05)。实验表明,大黄鱼在高蛋白质水平下能够有效调节糖酵解和糖异生关键酶活性,降低血糖含量及丙氨酸转氨酶、天冬氨酸转氨酶活性,并且未显著影响增重率;在低蛋白质水平,血糖含量和肝糖原含量随小麦淀粉水平的升高呈上升趋势,但增重率随着饲料小麦淀粉水平的升高呈上升趋势,表明在低蛋白质水平下高小麦淀粉水平对大黄鱼的生长有一定的改善作用。  相似文献   

12.
为探讨饲料淀粉水平对团头鲂成鱼生长、消化酶活性和肌肉成分的影响,选用初始均重为(161±2.7)g的团头鲂成鱼360尾,随机分成6组(每组3个重复),分别投喂含淀粉17.1%、21.8%、26.4%、32.0%、36.3%和41.9%的等氮等脂饲料9周。结果发现,团头鲂成鱼成活率和特定生长率不受饲料淀粉水平影响,但饲料添加适量淀粉能提高饲料和蛋白利用率,淀粉水平对肝脏和肠道中的总蛋白酶和纤维素酶活性不产生影响,却显著影响淀粉酶活性。肝体比、肝糖原和肌肉粗脂肪含量随饲料淀粉含量的增加而显著增加,血清血糖、胆固醇和甘油三酯含量不受饲料淀粉水平的显著影响,饲料中添加过量淀粉显著降低了血清补体3和补体4含量。以蛋白质效率和饲料效率为评价指标,经折线模型回归分析,得到团头鲂成鱼饲料中淀粉的适宜添加量分别为饲料干重的34.1%和31.4%,但考虑到血清补体的活性,团头鲂成鱼日粮淀粉水平不应超过36.3%。  相似文献   

13.
14.
为探讨饲料中添加不同小麦淀粉和脂肪水平对大黄鱼幼鱼生长、饲料利用以及糖代谢关键酶活力的影响,进行了为期8周的生长实验。设计了3个小麦淀粉水平(5%、10%和30%)和2个脂肪水平(5%和10%)的3×2的两因子实验,配制了6种等氮的饲料,分别喂养平均体质量为(6.75±0.12)g的大黄鱼幼鱼。结果显示,饲料中小麦淀粉和脂肪水平对大黄鱼增重率(WG)、特定生长率(SGR)、饲料效率(FE)、成活率(SR)、肝体比(HSI)和肥满度(CF)无显著交互作用,对脏体比(VSI)有显著交互作用。在同一脂肪水平下,淀粉水平为30%组WG和SGR显著高于10%淀粉组。不同小麦淀粉和脂肪水平对肝糖原含量无显著交互作用,而对肌糖原含量有显著交互作用,在饲料脂肪水平为5%时,30%小麦淀粉水平下的肝糖原含量显著高于10%和20%淀粉水平,10%淀粉水平下的肌糖原含量显著高于20%和30%淀粉水平;在脂肪水平为10%时,10%淀粉水平下的肝糖原含量显著高于20%和30%淀粉水平,而30%小麦淀粉水平下的肌糖原含量显著高于10%和20%淀粉水平。小麦淀粉和脂肪水平对血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、总胆固醇(TC)和葡萄糖(GLU)含量无显著交互作用,对总蛋白(TP)和甘油三酯(TG)交互作用显著。不同小麦淀粉和脂肪水平对肝脏脂肪酶活性有显著的交互作用,对淀粉酶活性无显著交互作用;同一脂肪水平下,脂肪酶的活性随着淀粉水平的升高而升高,同一饲料淀粉水平下,饲料脂肪水平为10%组的脂肪酶活性显著高于5%组。不同小麦淀粉和脂肪水平对肝脏丙酮酸激酶(PK)的活性有显著的交互作用,而对葡萄糖激酶(GK)、磷酸果糖激酶(PFK)、磷酸烯醇式丙酮酸羧激酶(PEPCK)、1,6-二磷酸果糖酶(FBPase)和6-磷酸葡萄糖酶(G6Pase)的活性均无显著交互作用。研究表明,当饲料脂肪水平为5%时,大黄鱼能够通过调节糖酵解关键酶活性及肝糖原含量来维持血糖平衡,改善对小麦淀粉的利用能力;而当脂肪水平为10%时,大黄鱼对小麦淀粉的利用能力降低。  相似文献   

15.
在高糖基础日粮中分别添加10 mg/kg罗格列酮、10 mg/kg格列本脲、4 g/kg 1,6-二磷酸果糖,饲喂初始重量为(4.87±0.12)g的异育银鲫(Carassius auratus gibelio),对照组喂基础日粮,饲喂56 d后测定了这三种糖代谢调控剂对异育银鲫生长、血液生化指标和糖原代谢的影响。结果表明:与对照组相比,饲料中添加罗格列酮后饵料系数显著降低(P<0.05),添加罗格列酮和格列本脲后,肝体比显著增大(P<0.01);与对照组相比,罗格列酮能提高血清总蛋白含量(P<0.05)、球蛋白含量(P<0.01),降低血糖的浓度(P<0.01);1,6-二磷酸果糖能提高血清谷丙转氨酶和谷草转氨酶活性(P<0.05),提高血清总蛋白、白蛋白和球蛋白的含量(P<0.01);格列本脲能提高血清谷丙转氨酶活性(P<0.05),提高总蛋白、白蛋白和球蛋白的含量(P<0.01)、降低血糖的浓度(P<0.01);③与对照组相比,罗格列酮能提高肌糖原的含量(P<0.05),格列本脲组肌糖原也有提高的趋势。  相似文献   

16.
The ability of diphenyl diselenide [(PhSe)2] to attenuate oxidative damage was evaluated in the liver, gills, brain, and muscle of carp (Cyprinus carpio) and silver catfish (Rhamdia quelen) experimentally exposed to fipronil (FPN). Initially, the fish were fed a diet without (PhSe)2 or a diet containing 3.0 mg/kg of (PhSe)2 for 60 days. After the 60-day period, the fish were exposed to 0.65 µg/L of FPN for 192 h. The results showed that carp exposed to FPN and not fed with (PhSe)2 exhibited acetylcholinesterase (AChE) inhibition in brain and muscle, and increased thiobarbituric acid-reactive substance (TBARS) in liver, gills, and brain. Furthermore, FPN decreased nonprotein thiols (NPSH) and δ-aminolevulinate dehydratase (δ-ALA-D) in carp liver and gills, and increased plasma glucose and protein levels. In silver catfish, FPN inhibited AChE and increased TBARS levels in muscle. In addition, glutathione S-transferase (GST) decreased in liver and muscle, and plasma glucose was increased. (PhSe)2 reversed some of these effects. It prevented the increase in TBARS levels in liver, gills, and brain in carp and in silver catfish muscle, and reversed the increase in plasma glucose levels in both species. Additionally, (PhSe)2 increased the NPSH levels in carp and silver catfish that had decreased in response to FPN exposure. However, (PhSe)2 was not effective in reversing the AChE inhibition in brain and muscle or the δ-ALA-D decrease in carp liver. Thus, (PhSe)2 protects tissues of both species of fish, mainly by preventing or counteracting the effects of FPN, on TBARS levels, antioxidants, and present anti-hyperglycemic property.  相似文献   

17.
Diets with increasing levels of potato and maize starch were fed to duplicate groups of maturing cod, Gadus morhuaL., from June 1991 to January 1992.The level of starch in the diet did not influence feed conversion factors, broodfish growth or gonadal development. Low levels of fillet glycogen were measured at all samplings, without variations according to dietary starch, or to developmental stage of the brood fish. During the reproductive phase no decreases were measured in relative liver size or liver protein, lipid or glycogen, indicating no net use of stored energy from the liver to build up gonads as long as the fish was offered feed. The variations in dietary starch vs. protein did not alter the composition of gonad dry matter, protein, lipid or glycogen levels. However, dry matter and protein levels increased during maturation in all groups. Plasma glucose levels were within normal ranges in all dietary groups at all sampling times, indicating no negative effects of high levels of dietary starch in brood fish, as also confirmed by stable and normal haematocrit, red blood cell count, and mean cell volume in blood. Haemoglobin, mean cell haematocrit and mean cell haemoglobin concentration decreased during the reproductive phase. Serum haemolytic complement activity did not vary between dietary treatments. Glycogen, dry matter, protein and lipid levels in eggs did not vary between dietary treatments of brood fish. Very low levels of glycogen were measured, suggesting that this energy reserve was of minor importance. Dry matter and lipid levels were quite stable in relation to egg developmental stage: protein levels decreased from day 0 until hatching.  相似文献   

18.
The effect of dietary carbohydrate complexity on growth, feed utilization and activity of selected key liver enzymes of intermediary metabolism were studied in gilthead sea bream juveniles. Four isonitrogenous (50% crude protein) and isolipidic (16% crude lipids) diets were formulated to contain 20% of pregelatinized maize starch, dextrin, maltose or glucose. Triplicate groups of fish (117 g initial weight) were fed each diet to near satiation during 6 weeks. No effect of dietary carbohydrate on growth was noticed. Feed efficiency was lower in fish fed the glucose diet than the maltose and dextrin diets. The lowest protein efficiency ratio was observed in fish fed the glucose diet. Six hours after feeding, glycemia was higher in fish fed the glucose diet than the maltose and starch diets. Liver glycogen content was unaffected by dietary carbohydrate complexity. Hepatic glucokinase (GK) activity was higher in fish fed the glucose and the maltose diets, while higher pyruvate kinase (PK) activity was recorded in fish fed the glucose diet than in fish fed the starch diet. Fructose-1,6-bisphosphatase (FBPase) and glucose-6-phosphate dehydrogenase (G6PD) activities were higher in fish fed the starch diet compared to dextrin and glucose diets. Data suggest that dietary glucose and maltose are more effective than complex carbohydrates in enhancing liver glycolytic activity. Dietary glucose also seems to be more effective than starch in depressing liver gluconeogenic and lipogenic activities. Overall, dietary maltose, dextrin or starch was better utilized than glucose as energy source by gilthead sea bream juveniles.  相似文献   

19.
本研究筛选到圆斑星鲽(Verasper variegatus)的性别相关基因sox9,并通过RACE技术获得了全长序列,基因全长为3287 bp,包括1431 bp的ORF,编码477个氨基酸,368 bp的5¢ UTR和1488 bp的3¢ UTR。在3¢ UTR中有多聚腺苷酸尾和加尾信号AATAAA。通过荧光定量PCR测定了sox9基因在圆斑星鲽成鱼不同组织中的表达水平,发现sox9基因在圆斑星鲽的脑、眼、鳃、心、肝、胆、肠、精巢、卵巢、肾和肌肉等各个组织中都有不同程度的表达。在鳃、脑和精巢组织中检测到较高水平的sox9转录,其中精巢中的转录水平显著高于其他组织,sox9基因在性腺中的表达显示出性别两相性差异。其在精巢中的表达水平要显著高于卵巢,说明sox9基因与雄性性腺发育相关。通过测定sox9基因在圆斑星鲽幼鱼不同发育时期(20、30、40、50、60、70和80日龄)的表达水平,发现其在20~50日龄表达量逐渐下降,在60日龄时表达量上升,推测表达量上升可能与幼鱼性腺分化相关。  相似文献   

20.
Gilthead seabream, Sparus aurata L., fed diets of equal vitamin C content were exposed to three different stressors–hyposalinity, shallow water and handling–and the effect of each on the internal homeostasis of the fish was evaluated. The individuals subjected to hyposaline stress exhibited no significant changes in plasma osmolality. Na+. Cl- K+, glucose, protein and triglyceride concentrations. Hepatic glycogen content was significantly lower in the fish subjected to the lower salinity (12%o), while the red muscle glycogen was unaltered. Amongst the challenged individuals, tissue ascorbate content was not significantly altered. Shallow water stress significantly diminished the liver and red muscle glycogen content, and lowered the liver. kidney and spleen vitamin C concentrations in the stressed fish. No significant changes were recorded in the plasma glucose, protein and triglyceride concentrations. In response to handling stress, no significant differences were detected in any of the measured parameters, with the exception of plasma glucose levels and the splenic L-ascorbic acid and ascorbate-2-sulphate (vitamin C2) contents. The lack of existing standardization of both experimental designs and analytical methods made comparisons of the present data with the work of other authors difficult, thus highlighting the necessity of coordinated research in this field.  相似文献   

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