Abstract:The Social-ecological system framework proposed by Ostrom is a new theoretical tool to analyse the sustainability of common pool resources. Based on the summary of international research on fisheries management under SES framework, this paper identifies the scale and object and then reviews the application process from 5 aspects: the identification of variables, the interaction of variables, the identification of system outcomes, the design of adaptive fishery management and the implementation and intendance of adaptive fishery management. Existing literature has provided a complete research process from the development of updated theoretic framework to the exploration of adaptive management practice, but there are still several problems, such as variable identification, mathematical reasoning and research scale development. However, the study of SES framework in fisheries management is very important for China's fisheries management theory research and fishery management system reform.

Abstract:As a family of carbohydrate binding proteins with Ca²⁺, C-type lectins play important roles in the first line of innate immune defense. In this research, a novel C-type lectin gene (LvLc1, GenBank Accession Number: KY937940) was cloned from Litopenaeus vannamei according to the data of shrimp transcriptome in our lab. The full-length cDNA consists of 1251 bp with an 891 bp open reading frame, encoding 296 amino acids. The deduced amino acid sequence contains a putative signal peptide of 19 amino acids. It also contains one carbohydrate recognition domains/C-type lectin-like domains (CRD). The potential carbohydrate-binding motif (QPD) presented in the CRD of LvLc1 may support its ability to bind galactose-type sugars. The deduced amino acid sequence of LvLc1 showed high identity with mannose-binding lectins of arthropod Procambarus clarkii and Pacifastacus leniusculus. It could be deduced that LvLc1 is a novel member of C-type lectin superfamily. The recombinant target protein (rLvLc1) was expressed by prokaryotic expression system. The LC-ESI-MS analysis showed that the peptide fragments of rLvLc1 were identical with the corresponding sequence of L. vannamei C-type lectin. rLvLc1 had agglutinating activity against main pathogens (G⁺, G^- and fungi) in aquaculture in a calcium-dependent manner. The agglutinating activity can be inhibited by multiple carbohydrates, such as galactose, mannose and lipopolysaccharide. These results suggest that LvLc1, as a Ca²⁺ dependent carbohydrate-recognition protein, is one of the important PRRs. It might play a crucial role in the innate immunity of the shrimp and it is expected to be applied to disease control.

Abstract:To explore the effects of three different aquacultures on planktonic ecosystem in semi-closed bay, the macro- and meso-zooplankton community, meso- and micro-zooplankton community and 12 kinds of associated environmental factors were studied inside and outside the fish cage aquaculture, kelp raft aquaculture, and farms in Xiangshan Bay via seasonal cruises during 2015. The results demonstrate that: compared with the control areas in the oyster farm, the macro- and meso-zooplankton community composition changed obviously, and the dominance of Acartia pacifica declined during summer and autumn, while that of Centropages abdominalis went up in winter; in the fish farm, the dominant species of macro- and meso-zooplankton changed, with the dominance of Centropages abdominalis declining during spring and winter, and dominant species composition changing obviously in autumn; however, in the kelp farm, there was no marked change in zooplankton community; moreover, the effects of the three different aquacultures on biomass, abundance and α-diversity of zooplankton community were nonsignificant. Analyzing the above results, combined with the hydrological characteristics in Xiangshan Bay and the environmental factors inside and outside the farms, we considered, the change in zooplankton community was a comprehensive result of oyster filter-feeding behavior and the poor water exchange capacity in Tie Harbor, and the zooplankton dominant species variation might relate to elevated total phosphorus content in the farm; in our study, fish cage aquaculture effects on environment and zooplankton were less, mainly due to the small aquaculture scale recently and good hydrodynamic condition in Xihu Harbor; the kelp aquaculture was inadequate to influence the water quality and zooplankton community, because of its small cultural scale and short cultural period every year (only in spring and winter). In addition, the variation in macro- and meso-zooplankton was more obvious than that in meso- and micro-zooplankton, which may be related to the higher stability in meso- and micro-zooplankton community.

Abstract:The southern Yellow Sea shows complex ocean-current and hydrological features, which caused complex spatial structure of fish assemblages that have been poorly understood. Based on seasonal bottom-trawl survey data collected from 2014 to 2015 in the coastal waters of southern Yellow Sea, we used multivariate methods to analyze the structure of fish assemblages, and compared the biomass, diversity, and dominant species among faunas. The results of Cluster and MDS showed that fish assemblage in the southern Yellow Sea could be divided into the Haizhou Bay fauna and the coastal waters of Jiangsu Province fauna. The fish assemblage in Haizhou Bay showed higher species biodiversity and average catches than those of the coastal waters of Jiangsu Province, whereas the relative biomass of warm-water and warm-temperate species in Haizhou Bay community was lower than the other. The dominant specie were Pholis angi, Hexagrammos otakii and Engraulis japonicas in Haizhou Bay with significant seasonal alternations, while they were Collichthys lucidus, Miichthys miiuy, Cynoglossus joyneri and Collichthys niveatus in coastal waters of Jiangsu Province with trivial changes. Our study demonstrated that fish assemblage in the southern Yellow Sea could be divided into two faunas with significant differences in fish assemblage structure, which were attributed to the different water masses, ocean currents, depth and bottom sediment types in the two regions.

Abstract:Red tide is one of marine disasters. It often causes great harm to fishery production and human life. Therefore, it is necessary to strengthen the early warning and forecast of red tide. However because the formation of red tide is very complex, it is very difficult to predict red tide. At home and abroad, there have been a lot of reports about the prediction and forecast of red tide. Different scholars have discussed the reasons for the formation of red tide using different research methods. In this study, 219 red tides data were collected in Fujian sea area from 2000 to 2016. The nonlinear relationship between the 5 meteorological factors, such as temperature, precipitation, wind speed, air pressure and sunshine, was established by using the BP neural network model. First of all, the total collected data of red tide and the corresponding meteorological data were divided into 3 sea areas data called Eastern, Central and South Fujian sea areas, according to their geographical locations, then the three groups of data were input into the model for it to learn and train. The results show that: 1) the 53 training samples in eastern Fujian sea area gave 45 correct predictions, the correct rate was 84.91%, and the 3 simulated prediction samples in the same area were all correct. 2) in 69 training samples of central Fujian sea area, 58 predictions were correct, the accuracy rate was 84.06%, and the 4 simulation predictions were all correct. 3) in 85 training samples in south Fujian sea area, 63 prediction results were correct, and the correct rate was 74.12%, and the 5 simulation samples were all correct. All the expected prediction results achieved the desired goals. Therefore, it is feasible to predict the occurrence of red tide based on the BP neural network model, which can provide a new way to forecast the red tide.

Abstract:To investigate the function of the pluripotency transcription factor Nanog in fish, this study examined the prokaryotic expression of the recombinant Nanog protein and generation of the rabbit anti-Nanog polyclonal antibody in blunt-snout bream. Firstly, MaNanog coding sequence was obtained from the ovary organ, and the full-length open reading frame or the partial fragment containing the homeodomain was inserted into the pET32a vector, respectively. Then the vectors were transformed into Escherichia coli BL21(DE3)pLysS, and the recombinant Nanog proteins were induced by IPTG. After optimization of expression conditions, the MaNanog-S protein was induced on a large scale and applied to antibody generation. Subsequently, the specificity of the antibody was examined by ELISA and Western blot. Results showed that the recombinant Nanog protein was highly expressed with 0.5 mmol/L IPTG induction for 4 h at 37 ℃. The polyclonal antibody could identify effectively the induced Nanog protein in E. coli, the endogenous MaNanog protein in adult organs, and the ectopic expressed MaNanog proteins in HepG2. Taken together, these results provided the research methods for prokaryotic expression of protein and preparation of specific antibodies, and also provided an effective tool to investigate the function of Nanog gene in fish.

Abstract:This experiment was conducted to investigate the effects of Enterococcus faecalis on growth performance, body composition, digestive ability and blood physiological and biochemical parameters of GIFT tilapia (Oreochromis niloticus). 300 fish of initial body weight (50.59±0.59)g were randomly divided into 5 groups, and each group was fed to triplicate repeats of 20 fish for 60 days. Each group was fed five isonitrogenous (crude protein 36%) and isolipidic (ether extract 6.75%) diets which added respectively 1.3×10²(control), 1.4×10⁵, 1.7×10⁶, 1.5×10⁷and 1.8×10⁸ CFU/g (measured) E. faecalis. The results showed as follows: Compared with control group, the final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR) and feed intake (FI) in the group of 1.5×10⁷ CFU/g reached a maximum and were significantly increased, and the feed conversion ratio (FCR) in this group was significantly reduced. Based on FBW, WGR and SGR, quadratic regression analysis projected the optimal concentration range for GIFT tilapia feed to 7.5×10⁷-1.1×10⁸ CFU/g. Compared with control group, the whole body crude protein content in all addition groups was significantly increased, and the whole body crude fat content in the group of 1.5×10⁷ CFU/g was significantly increased, there was not significant difference of the whole body moisture and crude ash content among all groups. The dry matter, protein, fat and ash deposition rate in the group of 1.5×10⁷ CFU/g are significantly higher than the control group. Compared with control group, the intestinal lipase activity was significantly increased in the group of 1.5×10⁷ CFU/g and 1.8×10⁸ CFU/g and intestinal protease activity was significantly reduced in the group of 1.8×10⁸ CFU/g. Adding E. faecalis to feed had no significant effect on intestinal amylase activity. The mean corpuscular volume, hemoglobin concentration and the number of platelets in the group of 1.5×10⁷ CFU/g are significantly lower than the control group. The erythrocyte count was not significantly different among all groups. The serum cholesterol, glucose content and the content of malonaldehyde in the group of 1.8×10⁸ CFU/g were significantly reduced compared with control group. Compared with control group, the activity of alkaline phosphatase in the group of 1.5×10⁷ CFU/g was significantly increased, but the activities of glutamic pyruvic transaminase and glutamic pyruvic transaminase in this group were significantly reduced. In conclusion, the suitable concentration range of E. faecalis for GIFT tilapia feed is 7.5×10⁷-1.1×10⁸ CFU/g, but adding E. faecalis has an adverse effect upon the ability of carrying oxygen of blood.

Abstract:Transposons are movable and extended elements, they are important parts in genome and can affect the genome evolution. Transposable activity is usually regulated by environmental factors. To discuss the influence of environmental stress on the activity of transposons, the zebrafish embryos at early stage were exposed to TCDD, Cu²⁺ and Cd²⁺ for two hours, respectively. Then the embryos were cultured in normal medium until 72 hpf. The total RNA of embryos were extracted and transcribed into cDNA by reverse transcription. Then the transcription activity of 9 transposons with complete gene structures after exposure were compared with that before by real-time quantity fluorescent PCR. The 9 transposons included 5 DNA transposons (Tc-a, Tc-b, Tc-c, Tc-d and Tc-e) and 4 retrotransposons (ZB-ERV-1, ZB-ERV-2, 2 L1-323 and L1-21). The results showed that the transcription activity of 8 transposons treated with TCDD obviously decreased, and that of one significantly increased; the transcription activity of 7 transposons treated with Cu²⁺ obviously increased, and that of 2 were significantly decreased; the transcription activity of 6 transposons treated with Cd²⁺ obviously increased, and that of 3 significantly decreased. Those results suggested that environment factors can significantly affect transposons expression activity, and environment stress could be the important reason for the variation of transposon activity. Those data play a very important role in evaluating and understanding the effect of environment factors on fish genome and transposon activity, and provide reference for further research on biology genome evolutionary mechanism.

Abstract:The purpose of this study is to find out the effects of compound Chinese herbs (Radix acutellariae, Puerarin, Coptidis, rhizome, Honeysuckle, Isatidis radix, Astragalus radix, Glycyrrhiza wralensis Fisch, Bupleurum, Angelica sinensis, Hawthorn, citrusa and Poria cocos) on growth digestive enzyme, immunologic factors and WSSV-resistant capacity of Litopenaeus vannamei and provide scientific basis for the healthy culture of it. Litopenaeus vannameis (0.026±0.007) g were randomly divided into 6 groups with 3 relicates per group and 160 shrimps per replicate. The shrimps were fed 28-days with basal diets supplemented with 0 (control group), 0.4%, 0.8%, 1.2%, 1.6%, 2.0% of compound Chinese herbs, respectively. The results showed that the growth performance (WGR、SGR、FR and SR) in experimental groups was significantly increased compared with that of the control group, and the 0.8% and 1.2% supplemental groups showed the best results. While the FCR was significantly decreased. The high activities of Digestive enzyme (Amylase, Potease and Lipase) and immunologic factors (SOD, GPT and GOT) on hepatopancreas of Litopenaeus vannamei were found in high supplemental groups, while with the time went by they were found in little supplemental groups, and the 0.8% and 1.2% supplemental groups showed the best results. Compared with control group, the content of MDA in 0.4%, 0.8% and 1.2% supplemental groups were significantly decreased. The shrimp in the control group and 0.4% supplemental groups were 100% death after infected with WSSV, however the time of the first death shrimp, the time of 50% death and the time of 100% death in 0.4% supplemental groups were delayed by 8, 16 and 8 h compared with that of the control group, respectively. The survival rate of 0.8% supplemental group was 33.3%, significantly higher than that of other groups. In short, compound Chinese herbs can promote growth, digestion, immune and WSSV-resistant ability, and 0.8% and 1.2% supplemental groups indicated best results.

Abstract:Precocity is a common problem in aquaculture of Chinese mitten crab (Eriocheir sinensis). To discover and clone important functional genes, the transcriptome of Y-organs of precocious and normal female crabs were sequenced by Illumina Hiseq 2000 high-throughput sequencing technology, and comparative transcriptome study was conducted. The results showed that precocious and normal crabs had 44 619 538 and 43 052 958 clean reads, respectively. Comparison between the sequencing data from precocious and normal female crabs revealed 2 655 differentially expressed genes. The differentially expressed genes GO functions in the transcriptome library were broadly divided into three major ontology (biological processes, cellular component and molecular function categories) of 42 branches. Data in the transcriptome from 134 differentially expressed genes could be divided into 4 classes taking the KEGG database as a reference, according to the metabolic pathway, including synthesis and degradation of ketone bodies, butanoate metabolism, neurotrophin signaling pathway, and base excision repair. By RNA-seq, we obtained abundant transcriptome information that could contribute to novel gene identification, causes and prevention of precocity, and research of Y-organs in Eriocheir sinensis.

Abstract:Adhesins are critical to the infectious pathogens, thus identification of novel adhesins is very crucial to understanding the pathogen's infection mechanism. In this study, we demonstrated that heparin can competitively inhibits the adhesion of Vibrio parahaemolyticus (VP) to Hela cells, which indicates heparin in ECM could be the cell receptor of VP. Using heparin-sepharose affinity chromatography, six heparin-binding VP out-membrane proteins (OMPs) are selected. The six corresponding recombinant proteins were expressed and purified. According to the result of function verification test, recombinant protein IMPDH、EF-Tu and OppA are capable of binding to the Hela cells surface. Furthermore, they can inhibit the adhesion of VP to Hela cells significantly. Our research shows that the three OMPs are candidates of VP adhesins.

Abstract:Pacific oyster (Crassostrea gigas) has the characters of strong environmental adaptation, fast growth, delicious flavor and rich nutrition. C. gigas is the most widely cultivated aquaculture species, the highest production economic shellfish in the world. When carrying out genetic breeding of animals, genetic parameters play important role in such aspects: individual genetic evaluation, selection response prediction, best breeding scheme design and improving the efficiency of selective breeding. This study conducted the experiment at the both north and south sides of the Shandong Peninsula. Ru Shan (RS) area is the main market of oyster in Shandong Province. Through market research, about 90% of the oyster come from RS area in the winter market of Shandong Province. Kong Tong Dao (KTD) area is another main market of oyster in Shandong Province, which can have up to 50%-70% market share in spring and summer of Yantai aquatic market. Genetic parameters of different strains and in different environment will be different. Although the same genotype materials, when environmental contributions to phenotypic variation change, its genetic parameters will be changed. Strictly speaking, the genetic parameters of specific groups can only be applied to a particular environment. In order to improve the efficiency of selective breeding, obtaining important economic characters of heritability and genetic correlation of genetic parameters in specific environment is very important. So far, no report of genetic parameters in C. gigas has been found about RS and KTD area. In order to find out heritability, genetic correlation and phenotypic correlation of growth traits in C. gigas in RS and KTD areas, this study was carried out by partial factor mating design and artificial insemination method to establish the family, and the oyster families were bred in RS and KTD areas. The mixed linear model was used to estimate genetic parameters of growth traits of the RS and KTD areas at the age of 188 days, 338 days and 474 days in C. gigas. The results show that the index of growth traits of C. gigas at different age, heritability in RS area was 0.28-0.55, which was medium to high heritability, heritability in KTD area was 0.34-0.63, which was high heritability. Compared with the RS area, heritability of growth trait in KTD area was height. By using the parent model, the age and location as fixed effects, and calculated heritability of the shell height (SH), shell length (SL), shell width (SW) and wet weight (WW), which were: 0.25±0.08, 0.29±0.09, 0.14±0.05 and 0.05±0.09. Genetic correlation and phenotypic correlation were varied at different areas and different age, but both correlations presented here were positive between each index. In general, the genetic correlation is higher than the phenotypic correlation between each index. Results of this study could provide data support of breeding route at both sides of north and south of Shandong Peninsula. The results also could help to obtain quantitative genetics parameter of growth trait in C. gigas in these areas.

Abstract:TLR6 (Toll like receptor 6) is a kind of pattern recognition receptors and plays an important role in resisting microorganism infection. To study the function of TLR6 in the immune response of P. fucata martensii, in this study, a full length of Pm-TLR6 was obtained using rapid amplification of cDNA ends (RACE) technology from P. fucata martensii. The expression patterns of Pm-TLR6 in all tissues and its sequential expression in the hemolymph after Vibrio harveyi stimulation and nucleus insertion operation were further detected by Quantitative Real-Time PCR technology. Results showed that the total length of Pm-TLR6 cDNA was 2295 bp, including a 5' UTR of 94 bp, a 3' UTR of 89 bp and an open reading frame (ORF) of 2112 bp which encodes 703 amino acids. Multiple sequence alignment indicated that TLR6 was highly conservative among species. The protein encoded by Pm-TLR6 has a transmembrane domain, several leucine rich repeats(LRRs) and a TIR domain, conforming to the characteristics of TLRs family. qRT-PCR data revealed that Pm-TLR6 was expressed in all tested tissues, including hepatopancreas, hemocytes, gill, gonads, adductor muscle and mantle, with the highest expression in hepatopancreas (P<0.05). After Vibrio harveyi injection, the expression level of Pm-TLR6 increased at 2 h (9 fold vs. control), then dropped to normal levels at 6 h and began to increase at 16 h, with the highest level of expression appearing at 24 h (29.4 fold vs. control, p<0.05). The result of nucleus insertion surgery showed that Pm-TLR6 expression level was not significantly changed at 5 d and 10 d, and began to increase at 15 d and 20 d (P>0.05). Its expression reached the maximum level at 30 d with significant difference (5 fold vs. control, p<0.05). These results indicated that Pm-TLR6 may play an important role in the immune defense reaction of P. fucata martensii.

Abstract:The aim of this study is to obtain the molecular characteristics of Streptococcus agalactiae (Group B Streptococcus, GBS) strains isolated from seven aquatic animals in China, and then analyze the epidemiology and transmission of GBS strains in these aquatic animals. In this study, a total of 10 GBS strains were isolated from seven aquatic animals. These isolates were analyzed by four typing methods: molecular serotype, MLST (Multilocus Sequence Typing), virulence genotype and prophage typing. In addition, the pathogenicity of GBS strains was evaluated by zebrafish. The ten GBS strains were divided into three types based on molecular serotype, namelyⅠa, Ⅰb and Ⅲ. The results of MLST indicated that serotypesⅠa, Ⅰb and Ⅲ were ST7, ST261 and ST739, respectively. The ten GBS strains were divided into three virulence genotypes (V1, V2 and V3) determined by PCR detection. The FWL1405 strain (Ⅲ-ST739) isolated from Hoplobatrachus chinensis carried 11 virulence genes (11/12, 91.7%), and the Ⅰa-ST7 GBS strains carried 10 virulence genes (10/12, 83.3%), and the Ⅰb-ST7 GBS strains were possessed of 7 virulence genes (7/12, 58.3%). Prophage typing showed that the ten GBS strains were divided into four types (P1, P2, P3 and P4), and the strains of P1 and P1 types belong to Ⅰa-ST7 GBS strains. These results revealed that GBS strains from seven hosts were divided into four genotypes, and the FWL1405 strain was the unique type: Ⅲ-ST739-V1-P3, determined by the previous four typing methods. However, tilapia GBS strains (LT-1, WC1535, WT1451 and WC15122) were divided into three genotypes:Ⅰa-ST7-V2-P1,Ⅰa-ST7-V2-P2 andⅠa-ST7-V3-P4. More important, the GBS strains isolated from Aristichthys nobilis, Aequidens rivulatus, and Oreochromis sp., have the same genotype:Ⅰa-ST7-V2-P2. The strains isolated from Trachinotus ovatus, Scortum barcoo, and Oreochromis sp., have the same genotype:Ⅰa-ST7-V2-P1. Furthermore, the same genotype of the GBS strains were found that isolated from Cirrhinus molitorella and Oreochromis sp.. Additionally, in this study, all the GBS strains have strong pathogenicity to zebrafish (Danio rerio). In conclusion, the genotypes of ten GBS strains were significantly different between amphibians (frog) and fishes. The possibility was little that GBS strains transmitted between amphibians and fishes. Notably, there were three genotypes of GBS strains from fishes, and the same genotype GBS strains were all found in tilapia. These results indicated that the possibility was great that GBS strains transmitted among these six species of fish, especially between tilapia and other fish species.

Abstract:To explore the protein distribution and physicochemical properties differences between striated(ST)and smooth(SM) muscle of Patinopecten yessoensis, muscle tissue sections were stained with hematoxylin and eosin and observed under microscope. Protein composition was analyzed by SDS-PAGE. The physicochemical properties were compared by salt-soluble and Ca²⁺-ATPase.It was found that the striated muscle fibers were thicker and denser than smooth muscle . Myorod only existed in the smooth muscle and was not present in the striated muscle. The content of paramyosin in the smooth muscle was 31%, however, it was only 11% in striated muscle. There was a complete difference between the two kinds of salt solution curves. The smooth muscle solubility was characterized by S-shaped curve, which was different from the striated muscle and showed a linear rise in the range of 0.05–1.0 mol/L salt concentration. Such differences were probably caused by paramyosin content. In addition, the optimal temperature of Ca²⁺-ATPase in smooth muscle myofibrillar and striated muscle myofibrillar was 35 ℃ and 30 ℃, and the activation energy was 23.4 kJ/moL and 11.3 kJ/moL, respectively.

Abstract:DNA methylation difference of eleven tissues of Oreochromis mossambicus, Oreochromis hornorum and “ Mohe” hybrid tilapia (O. mossambicus♀×O. hornorum♂), such as skin, muscle and gill etc. was analyzed to explore the change of methylation pattern during the interspecific hybridization using methylation sensitive amplified polymorphism (MSAP). 16 pairs of primers were used to amplify selectively. The results of electrophoretic banding analysis showed that there were differences in the methylation levels among these different tissues of the same species and between the same tissues among “ Mohe” hybrid tilapia and its parents; the average methylation level of these tissues from O. mossambicus, O. hornorum and “ Mohe” hybrid progenies was 32.21%, 38.03% and 29.77%, respectively. The methylation level of hybrid progenies was lower than those of the parental progenies. Most of the methylation patterns of the hybrid progenies were similar to the parental progenies (A, B and C types, 19.67%, 29.99% and 25.42%), while 24.92% cytosine demethylation and hypermethylation were found in the genome of hybrid progenies and the number of demethylation sites (E type, 15.73%) was greater than that of hypermethylation sites (D type, 9.19%). These results suggested that the genomic DNA hypomethylation and the reshuffling of the DNA methylation pattern in the hybrid progenies might be associated with the heterosis. The present findings established epigenetic foundation to further reveal the heterosis mechanism of tilapia.