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1.
We established a line (screened) of Portunus trituberculatus by selectively breeding individuals that survived from challenge with Vibrio alginolyticus, and compared the response of screened and unscreened (control) P. trituberculatus challenged with V. alginolyticus. We measured superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase, and peroxidase activity and the content of hemocyanin in the plasma and phenoloxidase activity in serum. The cumulative survival rate after 24-h challenge with V. alginolyticus was significantly higher in the screened crabs than in the unscreened crabs (P<0.05). T-SOD and PO activity were significantly lower in the screened stock than in the unscreened stock (P<0.05). POD, CAT, and ACP activity and hemocyanin content were significantly higher in the screened stock than in the unscreened stock. Our results suggest that the screened stock was more resistant to infection. Furthermore, the indices we measured may be used to evaluate the health state of P. trituberculatus. 相似文献
2.
Prepared in this experiment were six groups of diets, i.e. VC0, VC1, VC2, VC3, VC4 and VC5 with the contents of vitamin C (VCmg(100 g)−1 diet) of 0, 100, 200, 400, 800, and 1200 respectively. It was found that vitamin C increased the concentrations of immunoglobulin-like
(IgG-like, IgA-like and IgM-like) substances in the serum of Penaeus chinensis after a feeding period of 3 weeks. The differences among groups were significant (P<0.01), but there was no difference in the contents of complement3-like and complement4-like substances in the serum (P>0.05). Phenoloxidase (PO) activity in the serum of VC3 group shrimps was higher than that of VC0 and other groups, but no
significant difference was observed between VC0 group and other groups. Furthermore, bactericidal activity of the serum to
Vibrio parahaemolyticus in shrimps fed with the VC1 diet was higher than that in the other groups (P<0.01), while no difference was demonstrated among all groups for the bactericidal activity to Vibrio alginolyticus (P>0.05). It is, therefore, suggested that vitamin C (100–400 mg(100 g)−1 diets) could be used as an immunostimulant of P. chinensis. 相似文献
3.
For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was
injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was
observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum
antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood
granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase
activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes
and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune
factors such as antibody then played important role in response to anti-infection at the latter stage.
Supported by the National High Technology Research and Development Program of China (863 program, No. 2007AA09Z115) and Technology
Program of Xiamen (No. 3502Z73019) 相似文献
4.
The effects of several nutritional factors on the growth and eicosapentaenoic acid (EPA) production of diatom Nitzschia laevis were studied. 4 LDM (quadrupled concentration of the nutrient salt) was the optimal concentration of nutrient salt for the
growth and EPA production of N. laevis. The growth of N. laevis was inhibited when the glucose concentration was either lower than 10 gL−1 or higher than 15 gL−1. Both sodium nitrate and urea were good nitrogen sources for the growth and EPA production, while ammonium chloride seriously
decreased the dry cell weight (DW) and the EPA content. Silicate seriously influenced the growth of N. laevis. The maximum DW of 2.34 gL−1 was obtained in the presence of 150 mgL−1 Na2SiO3·9H2O. The EPA content remained almost the same when the silicate concentration was lower than 150 mgL−1; however, higher silicate concentrations resulted in a steady decrease of EPA content. Low medium salinity (⩽29) did not
seem to influence the DW of N. laevis, and high salinity resulted in a decrease of DW. The highest EPA content (4.08%) and yield (110 mgL−1) were observed at the salinity of 36 and 29, respectively. 相似文献
5.
Ubiquitin, a highly conserved stress-related protein, is assigned multiple functions, such as DNA processing, protein degradation, and ribosome synthesis. The Crassostrea hongkongensis ubiquitin gene (designated ChUbL40) was cloned by a combination of suppressive subtractive hybridization (SSH) and rapid amplification of cDNA ends (RACE). The full-length cDNA of ChUbL40 is 496 bp in length, consisting of a 5’ untranslated region (UTR) of 34 bp, a 3’-UTR of 75 bp and an open reading frame of 387 bp encoding a ubiquitin fusion protein of 128 amino acids. Analysis of the amino acid sequence of ChUbL40 reveals that UbL40 is highly conservative during evolution. The expression patterns of ChUbL40 gene in various tissues were examined by real-time PCR. The expression level of ChUbL40 in haemocytes is down-regulated at 4 h and gradually returned to its original level from 6 h to 24 h after Vibrio alginolyticus challenge. Our results suggest that ChUbL40 is ubiquitously expressed and plays an important role in immune defense against bacterial challenge. 相似文献
6.
A fast and indirect fluorescnet antibody assay for the Vibrio alginolyticus and V.Parahaemolyticus infecting the large yellow croaker has been developed.The specific antisera for the two strains of vibrio were prepared with New Zealand rabbit and the antiserum and cross-reactive efficacy was tested by coagulation in tube.It showed that the goat anti-rabbit IgG had been labeled by fuorescence isothiocyanate(FITC).The results showed that positive reactions were 100% for the large yellow croaker Pseudosciaena crocea with typical symptom of vibrio infection,while the positive reaction to the pathogen in healthy yellow croakers reached 40%,but seemed negative for aquaculter water.The results demonstrated that this fast and indirect fluorescent antibody assay can be used not only to test the vibrio pathogen in diseased yellow croaker but also in infected animals with no symptom. 相似文献
7.
INTRODUCnON-WatertemperatheanddissolvedoxygenareimportantenvironmentalfactorsinthegmwthanddevelOPmntofaqUaticorgAnsms.ThereareInanPublishedstUdiesontheox-.ygenconsUInPtionrate(OCR)oftheprawn')(WangJim,l986;WangDanghenetal-,199l;ZangWeilingetal-,l992,l993),buttheydidnotcontalndetailedinfonnaionabouttheeffectoftemPerabeontheOCR-ThePresentstudydetendnedtheOCRofju-venilesofChineseprawn,gianttiserprawnandgiantfreshwaterprawnthatwererearedatdifferenttemperatllresforaboutaweekattheCaoj… 相似文献
8.
Chemical characterization and composition of dissolved organic matter in Jiaozhou Bay 总被引：1，自引：0，他引：1
Biologically utilizable dissolved organic compounds, including dissolved organic carbon (DOC), dissolved carbohydrates (DCHO)
and dissolved free amino acids (DFAA) were analyzed in filtered surface seawater samples collected at 19 stations in Jiaozhou
Bay, China, on June 3, 2007. In these samples, concentrations of DOC, dissolved free carbohydrates (DFCHO), dissolved combined
carbohydrates (DCCHO), total dissolved carbohydrates (TDCHO) and total dissolved free amino acids (TDFAA) ranged from 141.7
to 191.1 μmol C/L, 1.98 to 18.18 μmol C/L, 5.04 to 24.90 μmol C/L, 14.52 to 30.36 μmol C/L, and 1.83 to 11.89 μmol C/L, respectively.
As a major component of the dissolved carbohydrates, the concentrations of DCCHO were about three times higher than those
of DFCHO. Three major constituents of the DFAA were threonine (23.0±5.7 mol%), glutamic acid (16.6±3.2 mol%) and arginine
(9.1±3.3 mol%). Based on the composition of DFAA, a molar C:N ratio of 3.60±0.75 in DFAA was derived, indicating longer carbon
chains in the amino acids. DCCHO (8.1%) was the most abundant fraction of DOM in most samples, followed by DFCHO (4.8%) and
TDFAA (2.7%). These DOM concentrations displayed a decreasing trend from the coast to the central region. Significant correlations
were found between the DCCHO and DFCHO concentrations (r=-0.724, n=19, P<0.001) and the DCCHO and TDCHO concentrations (r=0.506, n=19, P=0.027). 相似文献
9.
1 INTRODUCTIONA large-scale volcanic eruption can injectenormous amount of ash and dust into the atmos-phere, leading to local and short cooling due toshielding incoming radiation. During the past 2 to 3decades, accumulated evidence indicated thatlarge-scale volcano eruptions or series of volcanicactivity appears to coincide with climatologicaltransitions. For example, Robock (1979) indicatedthat volcanic eruptions played a role in forcing "Lit-tle Ice Age". Well-dated high-resolution co… 相似文献
10.
The shell color of Pacific oyster (Crassostrea gigas) is a desirable trait; but the nutritional studies on C. gigas with different shell colors have not been conducted. Through successive selective breeding, five shell color strains of black (B), purple (P), orange (O), golden (G) and white (W) C. gigas have been developed. The aim of this study was to evaluate the chemical composition and nutritional value of five shell color strains and one commercial population with a common color. The biochemical composition including moisture, total protein, glycogen, ash, total fat, fatty acids (FA), amino acids and minerals was detected. The results indicated that the protein (50.76%–56.57%) was the major component. The content of glycogen showed a significant difference between orange shell and golden shell strains, as well as between commercial population and golden shell strain. In addition, all shell color strains contained a large amount of essential amino acids (12.20–14.15 g (100 g)?1), of them leucine (2.81–3.29 g (100 g)?1) and lysine (2.79–3.28 g (100 g)?1) were predominant. The oysters were rich in polyunsaturated fatty acids (42.26%–45.24% of total fatty acid) with high levels of DHA (18.53%–21.16% of total fatty acid) and EPA (17.23%–18.68% of total fatty acid). Significant differences of mineral contents (Mg, Zn, Fe and Cu) were identified among the six populations. These results indicated that C. gigas with different shell colors presented rich nutritional value with high protein, glycogen, essential amino acids and polyunsaturated fatty acids. The biochemical composition obtained in this study is useful for selective breeding of C. gigas with different shell colors. 相似文献
11.
The temporal dynamics of the biomass, as well as the carbon (C), nitrogen (N), phosphorus (P) concentrations and accumulation
contents, in aboveand below-ground vegetation components were determined in the alpine steppe vegetation of Northern Tibet
during the growing season of 2010. The highest levels of total biomass (311.68 g m−2), total C (115.95 g m−2), total N (2.60 g m−2), and total P (0.90 g m−2) accumulation contents were obtained in August in 2010. Further, biomass and nutrient stocks in the below-ground components
were higher than those of the above-ground components. The dominant species viz., Stipa purpurea and Carex moorcrofti had lower biomass and C, N, P accumulations than the companion species which including Oxytropis. spp., Artemisia capillaris Thunb., Aster tataricus L., and so on. 相似文献
12.
The Gram-negative Vibrio parahaemolyticus is a common pathogen in humans and marine animals. Bacteria flagellins play an important role during infection and induction
of the host immune response. Thus, flagellin proteins are an ideal target for vaccines. We amplified the complete flagellin
subunit gene (flaA) from V. parahaemolyticus ATCC 17802. We then cloned and expressed the gene into Escherichia coli BL21 (DE3) cells. The gene coded for a protein that was 62.78 kDa. We purified and characterized the protein using Ni-NTA
affinity chromatography and Anti-His antibody Western blotting, respectively. Our results provide a basis for further studies
into the utility of the FlaA protein as a vaccine candidate against infection by Vibrio parahaemolyticus. In addition, the purified FlaA protein can be used for further functional and structural studies. 相似文献
13.
Fourteen stream segments were investigated throughout the Xin’an Spring in Shanxi Province, China in 2004. The variation ranges in stream size, current velocity, discharge, dissolved oxygen, and specific conductance were large. Twenty-two macroalgae species were found in the stream. Major divisions in terms of species numbers were Chlorophyta (59.1%), Cyanophyta (22.8%), Xanthophyta (9.1%), Rhodophyta (4.5%) and Charophyta (4.5%). The most widespread species, Cladophora rivularis (50.0%), also Oedogonium sp. (42.9%) and Spirogyra sp. (42.9%) were well represented throughout the stream, whereas another 10 species were found in only one sampling site. Total percentage cover varied from <1% to 90%. Red algae Batrachospermum acuatum and the charophytes Chara vulgaris have the highest percentage cover. Among the parameters analyzed, the stream width, specific conductance and dissolved oxygen were the ones that more closely related to the species number and percentage cover of macroalgal communities. The species number of each site was negatively correlated with dissolved oxygen content. The total percentage cover of the macroalgae was negatively correlated with the stream width and the specific conductance. 相似文献
14.
DONG Weihua YIN Xiuqin 《中国地理科学(英文版)》2007,17(2):166-172
Earthworms are the important constituents in the decayed food web and the main ecological conditioners in the process of decomposition and nutrient mineralization. The transformation of organic carbon (C) and total nitrogen (N) in the broad-leaved litters ingested by earthworms was researched by means of a laboratory experiment. Experimental samples were collected from broad-leaved Korea Pine mixed forest in Liangshui National Natural Reserve (47°10′50″N, 128°53′20″E) in the northeastern Xiao Hinggan Mountains of Northeast China. The contents of organic C and total N in earthworms, leaf litters and earthworm faeces were analyzed. Results show that the organic C content was in the fol- lowing order: leaf litters>faeces>earthworms, while total N content was contrary to that of the organic C. The organic C contents in the different leaf litters were in the following order: Tilia amurensis>Betula costata>Acer mono, whereas the total N contents in the different leaf litters were: Betula costata>Tilia amurensis>Acer mono. The contents of organic C and total N in the faeces from the different leaf litters were almost consistent with the contents of the leaf litters. After the leaf litters were ingested by earthworms, the organic C, which was transformed to increase earthworms' weights, ac- counted for 3.90%-13.31% of the total ingestion by earthworms, while that in the earthworm faeces accounted for 6.14%-13.70%. The transformed organic C through the other metabolism (e.g., respiration) of earthworms accounted for 75.04%-89.92%. The ingested organic C by earthworms was mostly used for metabolic activities. The N ingested by earthworms was less than organic C. It is estimated that 37.08% of total N was transformed to increase the earthworm's weight, 19.97% into earthworm faeces and 47.86% for the consumption of the earthworm's activities. The earthworms not only increased the content of organic C and total N in the soil, but also decreased the values of C/N in the soil and leaf litters. Earthworms play a major role in the leaf litters' decomposition and transformation. 相似文献
15.
Improvement in the osmoregulation capacity via nutritional supplies is vitally important in shrimp aquaculture.The effects of dietary protein levels on the osmoregulation capacity of the Pacific white shrimp(L.vannamei) were investigated.This involved an examination of growth performance,glutamate dehydrogenase(GDH) and Na+-K+ ATPase mRNA expression,,and GDH activity in muscles and gills.Three experimental diets were formulated,containing 25%,40%,and 50% dietary protein,and fed to the shrimp at a salinity of 25.After 20 days,no significant difference was observed in weight gain,though GDH and Na+-K+ ATPase gene expression and GDH activity increased with higher dietary protein levels.Subsequently,shrimp fed diets with 25% and 50% dietary protein were transferred into tanks with salinities of 38 and 5,respectively,and sampled at weeks 1 and 2.Shrimp fed with 40% protein at 25 in salinity(optimal conditions) were used as a control.Regardless of the salinities,shrimp fed with 50% dietary protein had significantly higher growth performance than other diets;no significant differences were found in comparison with the control.Shrimp fed with 25% dietary protein and maintained at salinities of 38 and 5 had significantly lower weight gain values after 2 weeks.Ambient salinity change also stimulated the hepatosomatic index,which increased in the first week and then recovered to a relatively normal level,as in the control,after 2 weeks.These findings indicate that in white shrimp,the specific protein nutrient and energy demands related to ambient salinity change are associated with protein metabolism.Increased dietary protein level could improve the osmoregulation capacity of L.vannamei with more energy resources allocated to GDH activity and expression. 相似文献
16.
The physiological responses of Nitzschia palea Kvtzing, a freshwater diatom, to elevated CO2 were investigated and compared with those of a marine diatom, Chaetoceros muelleri Lemmermann previously reported. Elevated CO2 concentration to 700 μl/L increased the dissolved inorganic carbon （D!C） and lowered the pH in the cultures of N. palea, thus enhancing the growth by 4%-20% during the whole growth period. High CO2-grown N. palea cells showed lower levels of dark respiration rates and higher Ik values. Light-saturated photosynthetic rates and photosynthetic efficiencies decreased in N. palea with the doubling CO2 concentration in airflow to the bottom of cultures, although the doubling CO2 concentration in airflow to the surface cultures had few effects on these two photosynthetic parameters. N. palea cells were found to be capable of using HCO5 in addition to gaseous CO2, and the CO2 enrichment decreased their affinity for HCO5 and CO2. Although doubled CO2 level would enhance the biomass of N. patea and C. muelleri to different extents, compared with the marine diatom, it had a significant effect on the specific growth rates of N. palea. In addition, the responses of photosynthetic parameters of IV. palea to doubled CO2 concentration were almost opposite to those of C. muelleri. 相似文献
17.
18.
Effects of nitrogen (N) and phosphorus (P) from different sources and at different concentrations on the growth of Levanderina fissa (= Gyrodinium instriatum) were studied in laboratory conditions. The findings might explain the recurrent blooms of this species in Pearl River Estuary, China. Results showed that nutrient limitation significantly inhibited the growth of L. fissa. The values of specific growth rate (μ max) and half-saturation nutrient concentration (K S) were 0.37 divisions/d and 8.49 μmol L?1 for N, and 0.39 divisions/d and 1.99 μmol L?1 for P, respectively. Based on K S values, dissolved inorganic N level in PRE was sufficient to support the high proliferation of L. fissa, while dissolved inorganic P concentration was far lower than the minimum requirement for its effective growth. L. fissa was not able to utilize dissolved organic N (DON) compounds such as urea, amino acids, and uric acid. However, it grew well by using a wide variety of dissolved organic P (DOP) sources like nucleotides, glycerophosphate, and 4-nitrophenylphosphate. The results from this study suggested that the ability in DOP utilization of L. fissa offers this species a competitive advantage in phytoplankton communities. The high level and continuous supply of DIN, enrichment of DOP, together with warm climate and low salinity in the Pearl River Estuary provided a suitable nutrient niche for the growth of L. fissa, and resulted in the recurrent blooms in the estuary. 相似文献
19.
ZHANG Zhicui XUEChanghu GAO Xin LI Zhaojie WANG Qi 《中国海洋大学学报(英文版)》2006,5(3):257-262
Monthly difference of the chemical composition of oyster cultured along the eastern coast of Shandong Province was analyzed. The components analyzed included glycogen, fatty acid and free amino acid （FAA）. The content of glycogen was high in January and March （2.89 and 2.82 g（100 g） ^-1 on average, respectively） and low in October （2.07g（100g）^- 1 on average）. The low content of neutral lipids in October reflected a relatively poor nutritional value of oyster （1.42 g（ 100 g）^- 1 on average）. The main fatty acids of oyster were palmitic acid （16：0）, oleic acid （18： 1）, eicosapentaenoic acid （EPA, 20： 5（0 3） and docosahexaenoic acid （DHA, 22：6（0 3）. The major FAAs of oyster were Taurine, Glutamicacid, Glycin, Alanine, Arginine and Proline. Taurine was the most abundant FAA with its content ranging from 603 mg（100 g） ^-1 to 1 139 mg（ 100 g） ^-1. The high contents of glycogen, polyunsaturated fatty acid and FAA showed that oyster cultured along the eastern coast of Shandong Province was nutritionally good in January and March. 相似文献
20.
Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate （^vSiO3-Si,^vPO4-P, ^vNH4-N, ^vNO2-N and ^vNO3-N） at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater （Cpw）, water and clay contents, and grain size of the sediments （CH2O, Cclay and GSsed）. The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area. 相似文献