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1.
The effect of the oral administration of high dosages of vitamins C and E on the innate immune system of the seabream was investigated. Gilthead seabream (Sparus aurata L.) were fed four different diets for 45 days: a commercial diet as control, a 3g/kg vitamin C-supplemented diet, a 1.2g/kg vitamin E-supplemented diet or a diet containing both vitamin supplements. After 15, 30 and 45 days, serum ascorbic acid and alpha-tocopherol levels, growth, complement titers and head-kidney leucocyte phagocytic and respiratory burst activities were evaluated. The results showed that serum vitamin levels reflected dietary input. Fish fed the vitamin C-supplemented diet showed an enhanced respiratory burst activity, while fish fed the vitamin E-supplemented diet exhibited increased complement and phagocytic activities. All of these positive effects were found in fish fed the joint diet, as well as a synergistically enhanced respiratory burst activity at day 30. The results demonstrate that in vivo vitamins C and E exert a synergistic effect enhancing the respiratory burst activity of seabream phagocytes.  相似文献   

2.
Phenoxyethanol is routinely used in seabream aquaculture to minimise fish stress response despite the secondary negative effects which have been observed. In this study, two different doses (60 and 200 microl/l) of phenoxyethanol, sedative and narcotic, were tested for their ability to reduce the stress caused in gilthead seabream (Sparus aurata L.) by crowding. Blood glucose and serum cortisol concentrations were measured as stress indicators. In order to study the effects of the treatment on the innate immune system of crowded specimens, two parameters of the innate immune response, serum complement activity and phagocytosis, were assessed. The results show that anaesthesia itself produced a stress response in the fish and affected the immune system, although the effects were greater with the narcotic dose. When the effects of anaesthesia on crowded fish were analysed, the results pointed to a slight reduction in stress as a result of the sedative dose of phenoxyethanol (lower increase in cortisol and lower reduction in phagocytosis). However, additive negative effects were seen in crowded fish when the narcotic dose of phenoxyethanol was used. Since the use of phenoxyethanol is a common practice in aquaculture, the significance of the results should be considered.  相似文献   

3.
A complex stressful event, which commonly occurs in modern aquacultural practices, was broken down into factors that were analysed both individually and jointly to assess their effect on two stress indicators (blood glucose and serum cortisol levels) and two activities of the innate immune response (serum complement and head-kidney leukocyte respiratory burst). For this, gilthead seabream (Sparus aurata L.) specimens were exposed to the following stressors: physical disturbance, crowding, anaesthesia with 2-phenoxyethanol and air exposure. At 0, 1, 2, 3 and 4 days post-stress, blood and serum samples were collected to measure glucose concentration and cortisol and complement levels, respectively. Head-kidney leukocytes were isolated and assayed to evaluate respiratory burst activity. The results show that physical disturbance, crowding and anaesthesia produced an occasional increase in glucose and cortisol concentrations. Crowding and anaesthesia induced a depression in complement activity, while hypoxia by air exposure caused a reduction in the respiratory burst. When all factors were jointly applied both humoral and cellular defences were compromised and cortisol values remained high throughout the experimental period. Any long-term effects of this abnormal serum cortisol levels on the immune system remain unknown.  相似文献   

4.
The presence of neuropeptide Y (NPY) in the brain and retina of gilthead seabream (Sparus aurata L.) was investigated for the first time. For this investigation we employed an immunoperoxidase technique and the western immunoblot analysis using an antiserum raised against porcine NPY. The results showed that NPY-immunoreactivity was widely distributed in the brain of S. aurata. In particular, we have found NPY-immunoreactive (ir) neurons in the area ventralis telencephali pars centralis and pars lateralis, in the area dorsali telencephali pars centralis subdivision two and in nucleus intermedius thalami. An intense NPY-ir was detected in the telencephalon, in the optic tectum, in the thalamus, hypothalamus and in the vagal lobes. Scarce positive fibres were seen in the olfactory bulbs. NPY-ir amacrine cells were observed in the retina. The western immunoblot analysis revealed a protein band with a mobility corresponding to that of synthetic NPY. Our findings are, in general, in agreement with those obtained in other teleosts. The extensive distribution of NPY indicates for this peptide a key role in basic physiological actions, including visual and gustatory inputs processing.  相似文献   

5.
The possible differences in the immunostimulant effects between whole wild Saccharomyces cerevisiae and a mutant strain (fks-1) administered in the diet to gilthead seabream (Sparus aurata L.) were studied. Fish were fed diets containing 0 (control) or 10 g whole wild yeast or fks-1 strain per kilogram feed for 2, 4 or 6 weeks. After each sampling, the innate humoral (complement, lysozyme and peroxidases) and cellular (intracellular peroxidases, phagocytosis, respiratory burst activity and cytotoxicity) responses were determined. Among the humoral responses, serum peroxidases and complement activity were significantly decreased after 6 weeks of feeding with the fks-1 strain-supplemented diet, while lysozyme activity increased after 2 and 4 weeks of feeding the fks-1 strain. Of the cellular responses studied, phagocytosis was increased to a significant degree at all the assayed times but only by the fks-1 strain-supplemented diet, while respiratory burst activity (after 4 weeks) and natural cytotoxicity (after 4 and 6 weeks) increased with either yeast strain. The intracellular peroxidase content was not affected by the dietary supplementation of either yeast strain. These results are discussed with a view to assessing the possible use of wild and/or mutant yeast strains for immunostimulant purposes in aquaculture.  相似文献   

6.
This paper describes an easy and sensitive flow cytometric assay for assessing the non-specific cytotoxic activity of gilthead seabream (Sparus aurata L.) head-kidney leucocytes against tumor target cells. Concomitantly, the cytotoxic process and the cell types involved were microscopically studied. The assay was based on the consecutive use of two fluorochromes. The targets were preincubated with 3,3'-dioctadecyloxacarbocyanine perchlorate (DiO) and then mixed with effectors. At the end of incubation time propidium iodide (PI) was added. While live effectors were non-fluorescent, live and dead targets retained the DiO (green) fluorescence and non-viable targets and effectors showed PI (red) fluorescence staining. The kinetics of the cytotoxic activity was studied from 10 to 240 min. Lymphocytes, monocyte-macrophages and granulocytes showed non-specific cytotoxic activity, as demonstrated by light and electron microscopy. In conclusion, the technique presented validates the effectiveness of a dual-color flow cytometric assay for assessing the activity of non-specific cytotoxic cells in fish.  相似文献   

7.
Immunoglobulin M (IgM) is a major component of the teleost humoral immune system. Despite the significance of IgM levels as an immune parameter, there are relatively few studies on changes induced in its total levels in serum. This study examines the effects of several immunomodulators (vitamin A, chitin, yeast cells or levamisole, which act as immunostimulants, and crowding, hypoxia or anaesthetics, which act as stressors) upon the total serum IgM levels of non-immunized gilthead seabream (Sparus aurata L.). Total serum IgM levels of fish fed with the assayed immunostimulant-supplemented diets were statistically higher than those in fish fed a non-supplemented diet, especially in the case of levamisole. On the other hand, serum IgM levels of fish subjected to different stressors were not affected by crowding, hypoxia or certain anaesthetics. However, benzocaine and a narcotic dose of 2-phenoxyethanol provoked a great reduction, while quinaldine sulphate increased IgM levels to a significant degree. These results show how the seric IgM levels can be differently affected by some immunomodulators and the important role they may play in the regulation of total circulating IgM levels in seabream. The possibility of using total serum IgM for assessing immunostimulation, disease diagnosis and stress symptoms during fish farming is discussed.  相似文献   

8.
The transverse red and white muscle area, the superficial red muscle fibres area and their percentages of mitochondria (%mit), myofibrils (%myof) and sarcoplasm (%sarc) were determined in the Mediterranean teleost gilthead sea bream, Sparus aurata (L.). Fish aged from hatching to 78 days were studied. The proportional growth of the red and white muscles was higher for the red muscle in the first half of the larval stage (1-35 days). Then the opposite relationship was observed. The hypertrophic growth of the superficial muscle fibres was continuous except in the first week after hatching. The percentage of mitochondria and percentage of myofibrils showed a significant change just after the half of the larval stage. Whereas the %mit of the superficial muscle fibres was higher than %myof from the first week after hatching to 35 days (average 66.64%), then the %mit decreased significantly and at 73-78 days both parameters were close to an average value of 50%. The meaning of these morphological changes is discussed in relation to the functional role of the red muscle of larvae and the onset of the gills respiration.  相似文献   

9.
The in vitro effects of four heat-inactivated bacterial species on the cellular innate immune responses of the gilthead seabream (Sparus aurata L.) were investigated. Head-kidney leucocytes were isolated and incubated for 30 min with two bacteria isolated from seabream skin (Pdp11 and 51M6; members of the Vibrionaceae and in the genus Shewanella) and two bacteria used as probiotics in humans and cattle (Lactobacillus delbrüeckii subsp. lactis and Bacillus subtilis) at 5 x 10(5), 5 x 10(6) or 5 x 10(7)CFU/ml. After incubation, different cellular innate immune parameters (leucocyte peroxidase content, phagocytosis, respiratory burst activity and cytotoxicity) were evaluated. The leucocyte peroxidase content was significantly higher after incubation with 51M6 at 5 x 10(7)CFU/ml. Head-kidney phagocytes were able to engulf the four bacterial species in all four cases, L. delbrüeckii subsp. lactis and B. subtilis being the most actively phagocytized. The incubation of seabream leucocytes with 51M6, L. delbrüeckii subsp. lactis and B. subtilis resulted in a great increase in respiratory burst activity. Cytotoxic activity was generally stimulated in a dose-dependent manner, the enhancement obtained with 5 x 10(7)CFU/ml being statistically significant. The usefulness of in vitro assays for screening and selecting candidate probiotic bacteria, as well as for optimising their effective dose, is discussed in relation with their immune-modulatory properties.  相似文献   

10.
An immunoblot technique for the detection of lymphocystis disease virus (LCDV) in naturally infected gilt-head seabream (Sparus aurata, L.) has been developed. A specific antiserum against a 60 kDa viral protein has been proven to be an appropriate tool for LCDV diagnosis either from inoculated cell cultures or from fish tissues using the immunoblot assay. The sensitivity of this technique varied between 10(-1) and 10(2) TCID50. LCDV has also been detected in fish tissues from both, diseased and asymptomatic gilt-head seabream. For the asymptomatic fish detection, a viral amplification step in cell culture and a subsequent viral concentration using polyethylene glycol (PEG) (600 wt) are required. On the contrary, immunoblot allowed the detection of LCDV antigens directly from tissue homogenates of diseased fish. The method described in this study shows higher sensitivity than classical detection techniques based on cell culture inoculation.  相似文献   

11.
The risk of fish pathogen transmission via eggs can be reduced by disinfection in ozonated seawater. The aim of this study was to determine the suitable conditions for ozone disinfection of the eggs of gilthead seabream Sparus aurata, sea bass Dicentrarchus labrax, red porgy Pagrus pagrus, and common dentex Dentex dentex. The eggs were disinfected with a concentration (C) of 0.5 mg of ozone/L of water at four different exposure times (T = 2, 4, 8, and 16 min). The hatching rate was determined in triplicate for each treatment. Bacterial colonies were counted on tryptic soy agar and thiosulfate-citrate-bile salts-sucrose agar. At the end of the experiment, bacterial load and hatching rate were assessed together to determine the optimal ozone treatment values, which were estimated in CT units (i.e., C [= 0.5 mg/L] x T [min]). Optimal values were CT 2-4 (T = 4-8 min; 18 degrees C) for gilthead seabream and red porgy, CT 2 (T = 4 min; 18 degrees C) for common dentex, and CT 4 (T = 8 min; 15 degrees C) for sea bass.  相似文献   

12.
Fibre-type differentiation of lateral musculature has been studied in gilthead sea bream Sparus aurata (L.) and sea bass Dicentrarchus labrax (L.) during post-larval development using ultrastructural, histochemical and morphometric techniques. The study showed three muscle layers: red, intermediate (or pink) and white. Initially, most of the red muscle showed low myosin ATPase (m-ATPase) activity fibres, whereas near the transverse septum some small high m-ATPase activity fibres appeared and later acquired a rosette aspect. Afterwards, during adult growth the red muscle showed a histochemical mosaic appearance. The pink muscle in sea bass was observed at the beginning of juvenile development by the oxidative technique (NADH-RT reaction) whereas in gilthead sea bream it was also observed at the end of larval development. The pink layer consists of high m-ATPase activity fibres. However, along the muscle development other low and moderate m-ATPase activity fibres were observed close to the red and white muscles, respectively. The white muscle of juvenile fish showed a histochemical mosaic appearance near the pink muscle. In adult specimens the mosaic white muscle spread out occupying the whole of the myotome. Morphometric analysis shows a significant increase in mean fibre diameter during post-larval development, as shown by the Student's t-test (hypertrophic growth). Skewness and kurtosis values of fibre diameters point to the generation of a new fibres from the myosatellite cells (hyperplastic growth).  相似文献   

13.
The histochemical profiles - mATPase and NADH-TR reactions - of the red and white muscle fibres of gilthead sea bream and sea bass were determined from the first week after hatching. Modifications of the mATPase technique by combinations of pH/time/molarity were carried out in order to compare the sensitivity of the myosin ATPase of each muscle fibre type of the lateral muscle. Results showed that the staining of muscle fibres was independent of small modifications in the technique. The intermediate ‘pink’ muscle was histochemically defined towards the end of the larval life and is considered to be implicated in the growth of the myotome. A layer of external cells was observed, by electron microscopical examination, between the connective tissue of the skin and the superficial red muscle fibres of larvae and postlarvae. It is suggested that the external cells are unlikely to be a source of red muscle fibres and implicated on the growth of the myotome, but rather a part of the dermatome. The timing, areas and mechanisms of hyperplastic growth of the myotome were defined and discussed.  相似文献   

14.
1. The effects of enzymatically hydrolysed whole Saccharomyces cerevisiae yeast (HY) and the pellets of yeast cell wall (YCW) on production traits, the microbiology and histo-morphology of the small intestine, and humoral immune responses against Newcastle disease virus (NDV), of Ross 308 broilers were investigated.

2. The control group received a maize-soyabean meal based basal diet for 42 days. In the treated groups the basal diet was supplemented with 1?g/kg of HY and YCW. There were 8 replicate pens per group (n?=?12 birds/pen).

3. HY and YCW supplementation improved live weight (P?=?0·006) and FCR (P?=?0·003) at 42-d as compared with the control group.

4. In the small intestine, Salmonella spp and Escherichia coli numbers were higher (P?=?0·01) in the mucosa and lower (P?=?0·01) in the digesta of the HY and the YCW fed groups at 25?d of age. Lactobacillus in the duodenal and jejunal digesta was higher (P?

5. Following oral challenge with Salmonella pullorum, Escherichia coli and Lactobacillus increased (P?P?

6. Supplementation of HY and YCW increased villus height in the jejunum (P?=?0·02), width of villus in the ileum (P?=?0·034) and number of goblet cells in villi of the jejunum (P?=?0·006) and ileum (P?=?0·01).

7. YCW increased antibody level against NDV at 21 and 42?d of age compared with the control and the HY supplemented diets (P?

8. It was concluded that HY and YCW improved growth and feed efficiency in broilers, and considering the improvements in production traits and humoral immune responses, yeast cell wall may be a better dietary tool than the hydrolysed whole yeast cell as a performance enhancer for broilers.  相似文献   


15.
Brown-marbled grouper Epinephelus fuscoguttatus which had been fed diets containing sodium alginate and kappa (kappa)-carrageenan at 5, 10 and 20gkg(-1), respectively after 0, 2, 4, 6, 8 and 14 weeks were examined for survival, growth, innate cellular and humoral responses as compared to the fish that fed control non-supplemented diet. Survival was 100% for the fish that fed all diets after 14 weeks and no significant difference in growth was observed among seven diets. The fish that fed a diet containing sodium alginate at 10gkg(-1), and fed a diet containing kappa-carrageenan at 5gkg(-1) over 2-8 weeks showed significantly increased leucocyte count, respiratory burst, phagocytic activity and phagocytic index, The fish that fed a diet containing sodium alginate at 5gkg(-1), and fed a diet containing kappa-carrageenan at 5gkg(-1) over 2-8 weeks showed significantly increased alternative complement activity (ACH50) and lysozyme activity. In another experiment, E. fuscoguttatus, which had been fed control diet, and all diets containing sodium alginate, and kappa-carrageenan after 14 weeks were challenged with Vibrio alginolyticus at 5.0x10(9) colony-forming units (cfu) fish(-1) and then placed in seawater of 34 per thousand. The survival of fish that fed a diet containing sodium alginate at 10gkg(-1) and kappa-carrageenan at 5gkg(-1) was significantly higher than that of fish which fed the control diet over 96-168h. It was concluded that E. fuscoguttatus which fed a diet containing sodium alginate at 10gkg(-1) or less, or fed a diet containing kappa-carrageenan at 5gkg(-1) enhance the innate immunity, and increase the resistance from V. alginolyticus infection.  相似文献   

16.
Olive flounder, Paralichythys olivaceus fed with pomegranate enriched diet and challenged with or without Philasterides dicentrarchi had a significantly higher white blood cell (WBC) count on weeks 2 and 4 than the infected group fed with non enriched diet (standard diet). Similarly the red blood cell (RBC) counts did not significantly change in control and treated fish on weeks 1 and 2. It was significantly increased in treated fish on week 2 when compared to the control. In both the groups the hemoglobin (Hb) and hematocrit (Ht) levels significantly increased on weeks 2 and 4. The mean corpuscular volume (MCV) did not significantly change at any time in both groups whereas mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) increased significantly on week 4 in the treated group. The leukocytes such as lymphocytes (Lym), monocytes (Mon), neutrophils (Neu), and biochemical parameters such as total protein (TP), glucose (GLU), and calcium (CAL) levels significantly increased in treated groups on week 2 or 4 as compared to the control. The scuticocidal activity and respiratory burst activity were significantly enhanced in treated groups with or without parasite on weeks 2-4. However, the serum lysozyme activity was significantly enhanced from weeks 1 to 4. The protective response in terms of cumulative mortality was low in groups fed with enriched diet against parasite when compared to control. Therefore, we suggest that pomegranate enriched diet following challenge with P. dicentrarchi restores the altered hematological and biochemical parameters, and improves the innate immune system in olive flounder against P. dicentrarchi.  相似文献   

17.
This study presents a depletion study for sulfadiazine and trimethoprim in muscle plus skin of gilthead sea bream (Sparus aurata L.). N4‐acetyl‐sulfadiazine, the main metabolite of sulfadiazine (SDZ), was also examined. The fish were held in seawater at a temperature of 24–26 °C. SDZ and trimethoprim (TMP) were administered orally with medicated feed for five consecutive days at daily doses of 25 mg SDZ and 5 mg TMP per kg of fish body weight per day. Two different diets, fish oil‐ and plant oil‐based diets, were investigated. Ten fish were sampled at each of the days 1, 3, 5, 6, 8, 9, 10, and 12 after the start of veterinary medicine administration. However for the calculation of the withdrawal periods, sampling day 1 was set as 24 h after the last dose of the treatment. Fish samples were analyzed for SDZ, TMP, and acetyl‐sulfadiazine (AcSDZ) residues by liquid chromatography–mass spectrometry. SDZ and TMP concentrations declined rapidly from muscle plus skin. Considering a maximum residue limit of 100 μg/kg for the total of sulfonamides and 50 μg/kg for TMP residues in fish muscle plus skin, the withdrawal periods of the premix trimethoprim‐sulfadiazine 50% were calculated as 5 and 6 days, at 24–26 °C, in fish oil (FO) and plant oil (PO) groups, respectively. The investigation of this work is important to protect consumers by controlling the undesirable residues in fish.  相似文献   

18.
The present study evaluated the effects of Saccharomyces boulardii on duodenal digestive enzymes, morphology and cytokine induction response in broiler chicken. A total of 200 birds were allotted into two groups (n = 100) and each group divided into five replications (n = 20). The control group was fed basal diet in addition to antibiotic (virginiamycin 20 mg/kg), and treatment group received (1 × 108 colony‐forming units/kg feed) S. boulardii in addition to basal diet lasting for 72 days. The results compared to control group revealed that adenosine triphosphatase, gamma glutamyl transpeptidase, lipase and trypsin activities were higher, while, no significant improvement was observed in amylase activities in the duodenum of the treatment group. Moreover, morphological findings showed that villus height, width and number of goblet cells markedly increased. Additionally, transmission electron microscopy visualized that villus height, width and structural condensation significantly increased in the treatment group. The immunohistological observations showed increased numbers of immunoglobulin A (IgA)‐positive cells in the duodenum of the treatment group. Meanwhile, cytokine production levels of tumor necrosis factor‐α, interleukin (IL)‐10, transforming growth factor‐β and secretory IgA markedly increased, and IL‐6 statistically remained unchanged as compared to the control group. These findings illustrated that initial contact of S. boulardii to the duodenum has significant impact in improving enzymatic activity, intestinal morphology and cytokine response in broiler chicken.  相似文献   

19.
This study was conducted to compare the effect of active dry yeasts (ADY) and yeast cultures (YC), two typical products of yeast preparations, on growth performance, carcass characteristics, meat quality and blood indexes in finishing bulls fed a high‐concentrate diet. Forty‐five finishing bulls (mean body weight (BW) ± standard deviation: 505 ± 29 kg BW) were allocated to three groups of 15 bulls and assigned randomly to one of three diets which were CON diet (basal diet), ADY diet (basal diet + Levucell SC) and YC diet (basal diet + Diamond V XP), respectively. After 98 days of trial, all bulls were slaughtered. The result showed that ADY rather than YC improved growth performance and carcass traits of bulls compared to CON. Moreover, both ADY and YC improved beef tenderness and changed blood indexes related to fat metabolism. In conclusion, ADY had more pronounced effect on growth performance of bulls fed high‐concentrate diet, and both ADY and YC improved the beef quality by intensive fat metabolism.  相似文献   

20.
Mycotoxins are structurally diverse fungal metabolites that can contaminate a variety of dietary components consumed by animals and humans. It is considered that 25% of the world crop production is contaminated by mycotoxins. The clinical toxicological syndromes caused by ingestion of moderate to high amounts of mycotoxins and their effect on the immune system have been well characterized. However, no particular attention has been focused on the effects of mycotoxins on the local intestinal immune response. Because of their location, intestinal epithelial cells (IECs) could be exposed to high doses of mycotoxins. As a component of the innate local immune response, intestinal epithelial cells have developed a variety of mechanisms which act to reduce the risk of infection by microorganisms or intoxication by toxic compounds. This review summarises the innate immune response developed by intestinal epithelial cells and reports the literature concerning the effects of mycotoxins on them. Particularly, the effects of mycotoxins on the maintenance of a physical barrier by epithelial cells will be discussed together with their effect on extrinsic protective components of the innate intestinal immunity: mucus secretion, antimicrobial peptide generation, IgA and pro-inflammatory cytokine release.  相似文献   

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