Abstract:The microsatellite primers of 8 pairs were used to study genetic variation of the grass carp (Ctenopharyngodon idella) in three progeny groups: YZ (Yangtze River ♀× Zhujiang River ♂),YY (Yangtze River ♀× Yangtze River ♂) and ZZ (Zhujiang River ♀× Zhujiang River ♂) from the populations of Yangtze River and Zhujiang River. The result suggested the number of alleles generated from each locus ranged from two to six at the eight assessed loci which showed rich polymorphism. These microsatellite primers could be used as good molecular markers for the genetic variation study of the grass carps. The number of effective alleles (N_e),observed heterozygosity (H_o),expected heterozygosity (H_e) and polymorphic information content were all the highest in YZ group as 2.811 1,0.984 3,0.639 9,0.559 8 respectively. Meanwhile,ZZ group had the lowest values: 2.675 1,0.865 0,0.612 9 and 0.528 3 respectively. The UPGMA and NJ trees based on genetic distance demonstrated that YZ group was genetically near to YY group. F_st and AMOVA analysis of all groups and loci indicated that there was moderate divergence between YY group and ZZ group. The highest genetic diversity that existed in YZ indicated this hybrid had the high potential for further breeding. There was obvious divergence between Yangtze River and Zhujiang River populations of grass carp.

Abstract:The bacterial diversity and community composition in hepatopancreas and bile of grass carp Ctenopharyngodon idellus were determined through seqencing the 16S rDNA gene library. The bacterial spectrum of hepatopancreas included eight species of Aeromonas,six species belonging to Pseudomonas,two species from Morganella,and one species each from Vibrio and Proteus. Aeromonas and Pseudomonas were two dominant genera with 36.17% and 31.91% relative abundance of community,respectively. Strains GZ16 of Aeromonas and GZ9 of Pseudomonas were two dominant species sharing same 12.77% relative abundance. The bacterial spectrum of bile included five species of Aeromonas,three species of Pseudomonas,and one species each from Morganella and Proteus. Same as found in hepatopancreas,Aeromonas and Pseudomonas were two dominant genera,sharing 35% and 27.5% relative abundance of community,respectively. Strain DN1 of Proteus was dominant species with 25% relative abundance of community. Comparative analysis showed that 10.5% community species in the hepatopancreas shared same as that in the bile,and 20% community species in the bile shared same as that in the hepatopancreas. This means there was a specific parasitic community in hepatopancreas or bile of grass carp. The results present in this research should be helpful to further understand the unknown roles of these bacteria in the hepatopancreas and bile,also to understand coevolution mechanism between bacterial community and host grass carp.

Abstract:cDNA encoding Lateolabrax japonica interleukin-8 (LjIL-8) open reading frame (ORF) was cloned by RT-PCR. Sequencing results showed that the LjIL-8 ORF nucleotide sequence was 300 bp in length, encoding a prepropeptide of 99 amino acids. The deduced mature amino acid sequence of LjIL-8 was compared with those of several fish and mammalian species. The results showed that the LjIL-8 had 23%-48% and 25%-92% identities with mammalian and fish IL-8s in deduced amino acid sequence. Phylogenetic analysis showed that the LjIL-8 had close relationship with Dicentrarchus labrax IL-8. Recombinant expression plasmid of pET-28a (+) was constructed by inserting the LjIL-8 ORF sequence into the prokaryotic expression vector pET-28a (+) . An expected protein band was observed on SDS-PAGE gel, recognized by monoclonal antibody against 6×His in Western-blotting assay.

Abstract:By means of histological section and H. E. dyeing, the histological characters were studied in the process of the ovarian development and Oogenesis of Hyriopsis cumingii. The mussels were cultured in the pond which could be used to reproduce. The ovarian development of Hyriopsis cumingii could be divided into five stages: proliferating period in February, growing stage in March, maturing stage started in April, spawning stage during April to November, resting stage during December to January. The oogenesis of Hyriopsis cumingii could be also divided into five stages: oogonia, early vitellogenic oocytes, vitellogenic oocytes, late vitellogcnic oocytes, and mature oocytes. The oocytes matured and spawned in different time. In the early time of oogenesis, the yolk stalk was not observed obviously. A big nucleolus was observed in the middle time of oogenesis, but no small nucleolus was observed.

Abstract:Porphyra haitanensis is one of the most important cultivars of marine algae in China,but its production and quality can be significantly jeopardized by execrable environments such as high temperature,therefore,selection of a heat-resistant strain will greatly benefit the nori industry. To this end,in the present study,we selected a meliorated strain Q-1 which has significant heat-tolerance to 30 ℃. Upon further characterizing the cultures of strains Q-1 and WT at 28 and 30 ℃,we show here that in a period of 15 days,the Q-1 conchospores survived at rates of 76.8% and 60.1%,respectively,while the WT conchospores survived at much lower rates of 15.9% and 6.7%. The Q-1 conchospores also divided at significantly higher rates of 100% and 83%,as compared with those of 90.4% and 63.8% for the WT conchospores,respectively. When the 35-day-old conchospore germlings were cultured at 24,28 and 30 ℃ for 25 days,the mean length of blades increased 19.4,10.8 and 2.8 times for Q-1,and only 7.3,1.7 and 0.9 times for WT compared with the original mean length,respectively. At 24,28 and 30 ℃,the blades of strain Q-1 grew 1.5,4.8 and 0.9 times faster than those of the WT,the blades of WT strain began to decay after being cultured for 15 days,however,the blades of Q-1 strain did not decay even being cultured for 25 days. The blades of Q-1 strain also showed excellent high-temperature tolerance during its large-scale cultivation in sea area. In the last autumn,the high temperature (28-30 ℃) continued for about two months after conchospore-seeding of Porphyra haitanensis,the blades of the WT decayed on a large scale and the production decreased significantly; while the blades of the Q-1 grew normally with rapid growth and did not decay,and the production was much higher than that of the WT. The above results indicated that the strain Q-1 is a fast growing and heat-resistant strain that may offer broad applications for the nori industry.

Abstract:A feeding experiment was conducted to examine the effects of dietary chitosan on growth, immunity and disease resistance for Nile tilapia, Oreoehromis niloticus with initial weight of (99.98±2.79) g. Nile tilapia (Oreoehromis niloticus) were inoculated with Aeromonas hydrophila and were fed with diets supplemented with appropriate amount of chitosan. 30 days after the inoculation, the agglutinating antibody titer were examined; 60 days after the inoculation, the relative rate of weight gain, specific growth rate, feed efficiency, protein efficiency, acid phosphatase, lysozyme activity and superoxide dismutase activity and bacterial relative percent survival by challenging with live A. hydrophila. The results showed that adding chitosan with a ratio of 0.6% into the diets can promote their growth and enhance the immune response, and chitosan can improve their non-specific defence and the resistance of Nile tilapia to immune response A. hydrophila.

Abstract:The objective of this study was to determine the effects of dietary lipid levels on the survival,muscle composition and digestive enzyme activities of juvenile GIFT strain Nile tilapia,Oreochromis niloticus. Triplicate groups of fish were fed for 90 days with the experimental diets formulated with increasing lipid levels (1.73%,3.71%,5.69%,7.67%,9.64% and 16.55% lipid) using fish oil (0%,2%,4%,6%,8% and 15% fish oil respectively ) as the lipid source. Survival rate throughout the growth trial ranged from 84.76 to 99.05%,but the survival rate of fish fed the 16.55% lipid was signifcantly less than the 3.71% lipid diets (P<0.05) . Daily feed intake (I_DF) was variable (0.94±0.04) to (1.34±0.02) g/d and signifcantly declined by dietary treatments when the lipid level higher than 7.67% (P<0.05) . Final mean body weight,and final mean body length were signifcantly greater for diets 7.67 L compared to the 1.73% and 16.55% treatments (P<0.05). Lipid content of muscle increased with increasing dietary lipid levels by the range of 2.29% to 4.27%,protein,ash and phosphorus contents had a rising trend. The protease activities of stomach and intestine had not signifcantly changed between treatments (P>0.05) ,but the lipase activities of foregut and midgut and amylase activities of foregut were significantly declined with increasing dietary lipid levels (P<0.05) . The results showed that high lipid level diets could cause the fish survival rate and daily feed intake to go down. With increasing dietary lipid levels for the tilapia,lipid content of muscle rose,protease activities of stomach and intestine changed a little,but lipase activity of intestine was restrained.

Abstract:A feeding study was performed to investigate possible performance enhancing effects of the rare earth-chitosan chelate (RECC) on intestinal structure of Carassius auratus L. Three hundred and sixty individuals (about 5.0 g) were allotted to four dietary treatments: a control group and three RECC-treated groups. RECC-treated groups were supplemented with 800 mg,1 600 mg and 2 400 mg of RECC per kg feed respectively. Each group had three duplicates. The whole feeding period lasted for sixty days.Resultsare as follows: RECC added in diet promoted the development of intestine. It was found that RECC-treated groups had higher numbers of plicamucosa than the control group,and plicamucosas became longer and narrower. Compared with the control group,the 0.08% RECC group had a greater number of plicamucosa (P<0.05),a lower width of policamucosa (P<0.05),and a higher number of goblet cells (P<0.05); the 0.16% RECC group had a greater number of goblet cell (P<0.01). Scanning electron microscope observation showed that microvilli in RECC-treated groups were more uniform and denser than the control group.

Abstract:Investigation on mass mortality of Trachinotus ovatus juveniles cultured in sea cage in Zhanjiang was carried out.The symptom of the sick fish was as follows:the skin was nigrescent,it swam twisty or circularly,responded slowly and anorexia.There was no infection of parasites or bacteria. The fish nervous necrosis virus was observed in the fish by PCR analysis. Two pairs of primers were designed based on the homogenus gene sequences from other fish nervous necrosis virus (NNV) submitted to GeneBank and the coat protein gene of Trachinotus ovatus nervous necrosis virus (PNNV) was cloned and sequenced. According to the analysis of similarity and phylogenelysis,the coat protein gene from PNNV had the highest identity of 99.2% to Epinephelus coioides nervous necrosis virus (ECNNV) at nucleotide level. Based on the result of molecular phylogenetic analysis,PNNV belonges to red-spotted grouper nervous necrosis virus (RGNNV) genotype. The cumulative mortality of all groups infected were 100% in artificial infection experiment by four kinds of infection. The infected samples were cloned and sequenced.These results suggested that the pathogen of mass mortality of Trachinotus ovatus juveniles cultured in sea cage in Zhanjiang was NNV.

Abstract:Gas chromatography method was developed for determination of trichlorfon and dichlorvos residues in fishery products by comparing chromatography conditions and the sample pretreatment. The samples were extracted with acetone-water (2+1, v/v) and discolored by activated carbon, lipids were removed by ZnAC, then the residues were re-extracted by dichloromethane and determined by gas chromatography with flame photometric detector (GC-FPD) . The linear range of trichlorfon and dichlorvos were 0.1~20 μg/mL and 0.025~5 μg/mL (r²≥0.999 5) . When spiked with 0.04, 0.4, 4 mg/kg of trichlorfon and 0.01, 0.1, 1 mg/kg of dichlorvos, the average recoveries ranged from 74.8% to 106.8% and their relative standard deviations (RSD) were between 1.12% and 13.7%. The detection limits of trichlorfon and dichlorvos were 0.04 mg/kg and 0.01 mg/kg separately. This method is simple, reliable and can be applied to detection of trichlorfon and dichlorvos residues in fishery products.

Abstract:In this study the temperature at different layers (5 m, 50 m, 100 m and 200 m) and the temperature structure (difference of water temperature between 100m and 200m) in the fishing ground of O.bartramii are analyzed based on the fishing data from Chinese squid jigging fleets in the northwestern Pacific Ocean and temperature data from August to October in 2003-2007. The results indicate that the fishing ground of O.bartramii is distributed in the waters of 151-156°E and 41-44°N during August and October, and the monthly temperature vertical structure is different in the fishing ground of O.bartramii. The optimal range of temperature at 5 m, 50 m, 100 m and 200 m layers and the difference of temperature from 100m to 200 m in the fishing ground of O.bartramii are 17-21 ℃, 9-12 ℃, 3-9 ℃, 2-7 ℃ and 0-0.03 ℃/m respectively in August. And they are 15-18 ℃, 8-11 ℃, 3-6 ℃, 2-5 ℃ and 0-0.02 ℃/m respetively in September, 14-17 ℃, 7-9 ℃, 2-8 ℃, 3-6 ℃ and 0-0.02 ℃/m respectively in October. The results also indicate that the fishing ground is distributed in the warm side of front at different water layers.

Abstract:The artificial reefs had been deployed for five years in Haizhou Bay. The resources of fish and macroinvertebrates were investigated in the artificial reefs and adjacent control areas in Haizhou Bay by bottom trawls in 2003,2004,2005 and 2007,with the aim of finding out the changes of community structure of the fish and macroinvertebrates. 96 kinds of fish and macroinvertebrates were found,including 53 kinds of fish,34 kinds of arthropods,7 kinds of Mollusca and 2 kinds of echinoderms,which accounted for 55.21%,35.42%,and 7.29% of the total number respectively. The fish and arthropods accounted for 90.63% of the total number and were the major species in artificial reef sea area. Besides,the results showed that the artificial reefs had obvious improvement on resource protection and restoration. The species composition,biomass,richness and diversity index of the fish and macroinvertebrates were quite different between seasons in artificial reef area and the annual average number of species,biomass,richness and diversity were higher than those of the control area. In addition,ABC curve indicated that the community structure of the fish and macroinvertebrates was unstable without the artificial reefs or with the reefs for one or two years. However,the community structure were stable in spring and autumn of the 4th year with the artificial reefs in the ecosystem.

Abstract:Five sampling sections were set in the Kunshan area of Dianshan Lake to study the ecological status of plankton after the complete removal of aquaculture net in spring 2008. The results showed that the temperature at different sampling sites of Kunshan area of Dianshan Lake wasn’t different. pH value was between 8.39 to 8.85. The conductivity value was 0.87-1.02 μs/cm. The dissolved oxygen was 8.92-12.71 mg/L. The value of transparency was very low,at 0.35-0.60 m. TN was all higher than 3 mg/L. TP was 0.11-0.57 mg/L. The concentrations of heavy metals were very low. In the study,phytoplankton was found 8 phylum 215 species,and the average density was 2.119×10⁷ ind/L. Rotifer was found 9 families 30 species,the dominant specie for the rotifer was Polyarthra trigla. Cladoceran was identified 8 genus 10 species,dominant specie was Bosmina coregoni. Copepod was identified 8 genus 10 species,dominant specie was Mesocyclops leuckarti. The results showed that the Kunshan Dianshan Lake was already eutrophic,in other words,after dismantling the aquaculture net,we must strengthen the water quality management,and there is no time to lose in ecological control and governance.

Abstract:A three-dimension numerical model to simulate the distribution of salt with a mobile boundary in the Yangtze River estuary is established in this paper. The model is based on an international three-dimension coastal ocean circulation model (ECOM model).Some complex topography is taken into account,including the deep waterway and the artificially enclosed tideland. The computed results match well with the observed ones,which imply that the model is capable of describing the temporal and spatial distribution of salt current in the Yangtze River estuary. The model imitates the 3D characteristics of saltwater intrusion,salt in the surface layer is lower and salt in the bottom layer is higher. From measurements during two tidal cycles by this model in February 1-2,7-8,2003,the sectional salt fluxes from the North Branch and the South Branch were calculated. The result shows that salt changes obviously during spring-neap tidal cycle. The sea transports a huge amount of salt into Yangtze River estuary during spring tidal cycle. This research provides the necessary data for prediction of saltwater intrusion and aproposed project for avoiding saltwater intrusion in the Yangtze River estuary.

Abstract:Seasonal species composition,abundance variations of the planktonic larvae were investigated during four cruises conducted in the Beibu Gulf,between Feb 1998 and May 1999. A total of 15 groups of planktonic larvae were identified,including Macruran larva,Alima larva,Ophiopluteus larva,Brachyura zoea,Brachyura megalopa and other Brachyura larva,six dominant groups,and other common groups. There were four groups which occurred all year round while the others occurred in some seasons. The results from 4 seasonal cruises suggested that the abundance of planktonic larvae in the Beibu Gulf ranged from 0.02 to 7.65 ind/m³ and averaged 0.50 ind/m³. The average abundance of planktonic larvae was 0.86,0.40,0.32,0.12 ind/m³ in summer,spring,autumn and winter respectively. The density centre was moving anticlockwise from the northeast of the Gulf in spring to the northwest in summer and autumn,then back to the northeast in winter. The K-dominance curves suggested that the community diversity of the planktonic larvae decreased from spring,winter,summer to autumn in sequence,but the range of seasonal variations was not so obvious. And the canonical correspondence analysis (CCA) showed that the abundance of planktonic larvae was affected greatly by the sea water temperature and pH,but less by the salinity and DO.

Abstract:In order to investigate the differences in water quality and phytoplankton diversity between two depth ponds and provide the theory basis about transforming traditional pond into deep pond,an experiment was carried out to analyze the composition,distribution and community structure of the phytoplankton and physical and chemical indexes in three shallow pond (1.3±0.1) m and in three deep pond (2.2±0.1) m in Zhuhai Zhishan aquaculture base. The results indicated that the density,composition and predominant species of phytoplankton were significantly different between two depth ponds. The density,richness index,diversity index and evenness index of phytoplankton in deep pond were significantly lower than those in shallow pond. The contents of total phosphorus (TP) and total nitrogen (TN) were also significantly different between ponds. The contents of TP and TN in deep pond were significantly higher than those in shallow pond. The significant correlations between the density of phyloplankton and the contents of TP or TN were found in deep pond,but not in shallow pond.

Abstract:Freshwater nitrification biofilter was domesticated to seawater nitrification biofilter by salinity gradient change method. Microbial community structure response to salinity domestication process was determined by denaturing gel gradient electrophoresis (DGGE) profiles of 16S rDNA V3 region. ATP contents were determined with luciferin-Luciferase mixtures method under different salinity impact.Resultsshowed that microbial community of the biofilm changed significantly before and after the salt change: the dominant species of fresh-water biofilm were Beta proteobacteria, and Delta proteobacteria; after the salt flush, the dominant species of the biofilter came into Stenotrophomonas of Gamma proteobacteria, Alpha proteobacteria, and Paenibacillus, etc. The biofilms’ ATP contents decreased by 17.4% (salinity 15) and 47.7% (salinity 25) after different salinity flush separately. In 25 ℃ biofilm cultivation condition, it takes 70 days to cultivate nitrifying biofilm in salinity 25 seawater; it takes 61 days that freshwater nitrifying biofilm domesticated directly for salinity 25 seawater nitrifying biofilm; it takes 56 days that freshwater nitrifying biofilm domesticated for salinity 10 seawater nitrifying biofilm firstly, then started for salinity 25 seawater nitrifying biofilm.

Abstract:The growth of spoilage bacteria and the rate of production of metabolite for sterile Pseudosciaena crocea tissue blocks inoculated Shewanella putrefaciens and Pseudomonas spp. stored aerobically at 5 ℃ were respectively assayed. The yield factor for production of metabolite and the cell concentration determined at the time of off-odour detection were used as quantitative measurements of microbial spoilage ability. At spoilage point,the logarithm counts of the N_s (minimum number of spoilage bacteria) of Shewanella putrefaciens and Pseudomonas spp. were 9.14 lg cfu/g and 9.25 lg cfu/g,respectively. Adopting Gompertz regression equation to describe the growth curve of Shewanella putrefaciens and Pseudomonas spp.,we gained growth kinetics model parameters of both spoilage bacteria. The μ_max (maximum specific growth rate) of Shewanella putrefaciens and Pseudomonas spp. were 0.071 4 and 0.070 0,the logarithm counts of the N_max (maximum number of bacteria) of them were 9.45 lg cfu/g and 9.37 lg cfu/g,respectively. The results showed that their μ_max were basically the same and both of N_max were more than N_s of them,suggesting both spoilage organisms could be responsible for spoilage of Pseudosciaena crocea. The Y_TVBN/cfu and Y_TMA/cfu of Shewanella putrefaciens were 1.38×10^-10 mg-N TVBN/cfu and 1.31×10^-10 mg-N TMA/cfu,respectively. The Y_TVBN/cfu of Pseudomonas spp. was 1.18×10^-10 mg-N TVBN/cfu. The quantitative results indicated that the spoilage ability of both spoilage bacteria was equivalent. Because Shewanella putrefaciens and Pseudomonas spp. were the dominant spoilage bacteria when Pseudosciaena crocea was stored aerobically at low temperature,also based on the concept of SSO (Specific spoilage organism),Shewanella putrefaciens was the most dominant spoilage bacterium in the specific spoilage organisms,followed by Pseudomonas spp.

Abstract:In this paper, cartilages of the Amur sturgeon were used as the material to study the optimized protocol for the alkali extraction technology of chondroitin sulfate based on the process of alkali extraction-enzymatic hydrolysis-alcohol precipitation. By single factors (different alkali concentration, alkali liquor temperature, alkali liquor content) and orthogonal test, the effects on yield of product and hexosamine content were studied. The results showed that the optimum alkali extraction technology was as follows: adding 2 times amount of 6% NaOH, and stirring in water at 40 ℃ for 4 h. And the yield of chondroitin sulfate made by this technology reached 40.45%, the quality met the requirement of WS1-C3-0030-2000.The breast cancer cell line (MCF-7 cell) , gastric cancer cell line (MGc803 cell) and hepatoma cell line (SMMC7721) were treated 72 h with the pure and crude samples of sturgeon chondroitin sulfate, and its IC₅₀ were 7.28 mg/mL、7.68 mg/mL、4.25 mg/mL and 8.86 mg/mL、9.27 mg/mL、7.37 mg/mL respectively, its antitumor activities were similar to the pure and rough samples of shark.

Abstract:The phase equilibrium curves of aqueous LiCl solution and air under isothermal and adiabatic absorption processes were plotted respectively to design the absorption towers which are used in liquid desiccant air conditioning systems. The researches showed that the former curves were influenced by the temperature of the solution while the latter were influenced mainly by the concentration of the solution. The latter curves also showed that the latent heat of condensation of water vapor and the differential enthalpy of dilution of the solution caused the absorption system to reach the heat and mass balance situation much faster than isothermal process, which meant that lower height tower could be adopted for adiabatic processes. The required solution’s volumetric flux was calculated using the phase equilibrium curves and the results showed that the mass and heat balance relations should be considered simultaneously to get reasonable results, while only mass balance relations were used in traditional calculating methods.

Abstract:In the late Qing Dynasty, there was a hard practical process of political transition ideologically originated from abroad, such as Establishment of Yamen, the Reform Movement of 1898 and the New Constitutionalism. However, all these initiatives finally failed and the Qing Government was ended. Needless to say, the failure of the late Qing political transition was the various “forces” effects. From a macro perspective, the social and historical conditions at the time determine the success of any political transition because of many politically checking factors like the historical traditions, social reality, subjective will and the other factors. Through combing of the late Qing history carefully, I think, there are three key reasons leading to the failure of political transition. (1) Lack of motivation of the transition was caused by the traditional political culture; (2) It was lack the organizational system because of the traditional literati class changing radically weather. (3) The transformation lacking the spirit foundation was caused by the spirit of the cornerstones of Confucianism as the core collapse of traditional ideology. It is useful to study and draw experience from the historical practice in that period of time in order to promote political development in China nowadays.

Abstract:More and more colleges build branch campuses in suburb, and this has brought about many new problems for the graduates employment work. It is very essential for the college employment department to study the new problem by the conditions of suburban education, make and implement policies of job market for college graduates. The paper analyzes new problems of graduates employment work by the conditions of suburban education. In order to establish a stable, orderly, normal and healthy graduate employment market, suburban college should implement eight major initiatives for suburban market construction employment of college graduates. The eight initiatives are: actively setting up multi-dimensional linkage model among school and companies; strengthening to manage graduates-demanding units; building a effective job market exploiting team; implementing a market exploiting policy in linkage model; quickening up to promote multiple function information platform establishment; developing and using alumni resource; pushing up to set up employment base; continuously innovating the form and carrier of campus job recruitment.