Abstract:Long non-coding RNA (lncRNA) plays an important role in the regulation of epigenetics, transcription, and post-transcription. To understand the regulation mechanism of immune response to Vibrio harveyi, we performed lncRNA identification and differential expression analysis from RNA-seq data. We obtained a total of 4 584 lncRNA loci, containing 5 714 transcripts in this study. The comparison of basic characteristics between lncRNA and the coding gene showed that the GC content of lncRNAs was lower than that of coding genes, and single exon genes number was greater than that of coding genes, and the average transcripts length of lncRNAs was longer than that of coding genes, and the average expression of lncRNAs was slightly lower than coding genes. We screened 818, 813, 261 and 140 differentially expressed lncRNAs by differential expression analysis in four comparisons of Cynoglossus semilaevis groups (CsRU vs CsSU, CsRC vs CsSC, CsRC vs CsRU, CsSC vs CsSU), respectively. Additionally, we preliminarily analyzed the expression patterns and the relationship of differential expression of lncRNAs from those four groups. Through co-expression analysis, a total of 14 539 types of interaction relationships were detected between 285 lncRNA and 274 coding genes. We performed GO annotation and screened 7 key lncRNA. The qRT-PCR confirmed that the expression patterns of lncRNAs were consistent with their expression levels bases on transcriptome data. This study provides some of reference data for studying the role of lncRNA in the immune response against V. harveyi.

Abstract:Tumor necrosis factor (tnf) is a pro-inflammatory factor and plays an important role in immune response to bacterial and viral infections and clearance of infected cells. In this study, zebrafish were intraperitoneally (i.p.) injected with immunostimulants, bacterial or viral pathogens, and the expression of tnfα and its receptor (tnf receptor superfamily (tnfrsf) member 1 a) was analyzed by real-time PCR in kidney and spleen. The results showed that tnfα and tnfrsf1a were constitutively expressed in all the tissues analyzed. Lipopolysaccharide (LPS) and polyinosinic acid-polycytidylic acid (poly(I:C)) modulated the expression of tnfα and tnfrsf1a. Intraperitoneal injection of Aeromonas hydrophila led to significant increases of tnfα expression in spleen (at 48 h and 72 h) and kidney (at 72 h) and that of tnfrsf1a in spleen (at 48 h). In contrast, in fish i.p. injected with Edwardasiella tarda, the tnfα expression increased significantly at all the time points whilst totally inhibited in spleen. Increase of tnfrsf1a expression was also seen in both tissues at 6 h and 72 h. The expression levels of tnfα and tnfrsf1a were significantly elevated at the early stage of infection with SVCV, with that of tnfrsf1a detected significantly higher in kidney of infected fish than that in the control group throughout the infection period (1-7 d). The results indicate that tnfα and tnfrsf1a play important roles in immune defence against bacterial and viral infections.

Abstract:Vibrio parahaemolyticus is a zoonotic pathogen that poses a serious threat to animal, fish and human health. In order to study the dynamic process of host neutrophils and bacteria infection, we established a model of local infection of the 48 hours post fertilization (hpf) zebrafish larvae otic vesicle infected with the V. parahaemolyticus strain labelled with red florescent protein (Vp57^RFP) in this study, and the Escherichia coli Ec01 strain was used as a control to systematically compare the median lethal dose (LD₅₀) and survival curves, infection process and dynamic process of interaction with neutrophils of V.parahaemolyticus and E. coli, respectively. RT-qPCR verified the expression levels of the inflammation-related genes il1b and il10. The results showed that the LD₅₀ of E. coli and V.parahaemolyticus infected zebrafish larvae were 1.14×10¹¹ CFU/mL and 7.90×10⁷ CFU/mL, respectively. Compared to E. coli, V. parahaemolyticus recruited faster and more numerous neutrophils during dynamic infection imaging, and induced more il1b and il10 genes expression level that caused strong inflammatory response in zebra fish larvae at the same time point. Based on the above research, we successfully established the model of V.parahaemolyticus-otic vesicle zebrafish larvae infection, which provides a basis for further study of the dynamic process of neutrophil clearance of Vibrio parahaemolyticus infection and the in-depth revealing of the innate immune response mechanism.

Abstract:In order to investigate growth and morphological differences among Larimichthys polyactis, L. crocea and their hybrids (L. polyactis ♀ × L. crocea ♂), the body weight of the three kinds of fish were compared in 3, 4, 6, 8, 11, and 15 month of age, and the phenotypic traits (total length, body length, head length, trunk length, tail length, caudal peduncle length, caudal peduncle depth, body depth, body weight, and condition factor) variations of 8 month of age L. polyactis, L. crocea and the hybrids were measured and analyzed. The results showed that the body weight of L. polyactis was significantly higher than that of L. crocea and the hybrids before 4 month. From 4 month of age, body weight of the hybrids greater than that of L. polyactis, and L. crocea, but the body weight of L. crocea higher than the hybrids at 15 month of age since the growth rate of L. crocea increased obviously from 11 month of age. Thus, at last, the body weight of the hybrids was between in those of the parents, which means the hybrid showed a mid-parent heterosis. In the results of morphological differences analysis, there were significant differences in phenotypic traits among L. polyactis, L. crocea and hybrids (P<0.05). In which, both the body weight and condition factor of the hybrids were significantly higher than the two parental groups (P<0.05). A cluster analysis revealed that the difference between hybrids and female parents is less than the difference between that and male parents, suggested the hybrids resemble female parents in morphological traits. A discriminant analysis for the morphological traits of the three groups was carried out, and three discriminant functions were established for the three groups, and resulting in a comprehensive discriminant rate of 80.6%. In which, the discriminatory accuracy of L. crocea was as high as 94.6%, which was higher than those of the L. polyactis (73.5%) and hybrids (74.6%), suggested again that the hybrids has a significant maternal effect on morphological traits. The purpose of this study is to provide theoretical basis for the morphological and phylogenetic identification and hybridization selection of L. polyactis, L. crocea and hybrids. The study would be beneficial for identifying groups, and for determining genetic relationships and breeding.

Abstract:The countershading formed by deep body color of dorsal surface and shallow body color of venteral surface is beneficial to avoid enemies and prey, and is more common in marine fishes. In order to understand the ecological adaptation of the marine bony fishes and the formation of pigment cells in the dorsal and venter surface, six kinds of marine pelagic fishes and five kinds of demersal fishes were collected, respectively. The results show that no matter the marine pelagic fishes (including Megalaspis cordyla, Hemiramphus far, Seriola quinqueradiata, Trachurus japonicus, Decapterus maruadsi, Scomberomorus niphonius) or marine demersal fishes (Muraenesox cinereus, Synechogobius ommaturus, Trichiurus japonicus, Aluterus monoceros, Harpadon nehereus). Both melanocytes and xanthophores are more in dorsal than in venter, and the difference between dorsal and venter is significant. Compared to the offshore demersal fishes, the countershading in these offshore pelagic fishes is more obvious. The iridocystes are present in both the skins of dorsal and venter, in the venter of marine demersal fishes most of pigments are iridocystes. There are few of the erythrophores in the demersal fishes, but more erythrophores can be seen in marine pelagic fishes. In summary, the investigation shows that the countershading mainly depends on the amounts of both melanocytes and xanthophores in the dorsal skin, and the venter color is related to iridocystes in marine bony fishes.

Abstract:The 60-day-old blades of wild-type strain (PS-WT) and mutant strain (PS-L) of Pyropia suborbiculatain were used as experimental materials to obtain their isolated cells by enzymatic hydrolysis, and then observe the development and morphology of isolated cells in submerged culture. Meanwhile, we also investigated the effects of temperature and light intensity on the development and differentiation of isolated cells. The results showed that the isolated cells could develop into different types of regenerative plants: normal blades, abnormal blades, cell-masses and sexual cell-masses. In the range of 10-80 μmol photons/(m²·s), there was no significant difference in the percentage of normal blades, cell-masses and conchocelis of the two strains; appropriate light intensity [40-60 μmol photons/(m²·s)] could promote the release of monospores of regenerative plants. In range of 18-24 ℃, the proportion of normal blades and abnormal blades of two strains had no significant difference. However, high temperature (27-30 ℃) could inhibit the formation of normal blades, promote the formation of abnormal blades and the release of monospores the of regenerative plants.

Abstract:In order to study the effect of Bacillus on eukaryotic microbial community structure and physical and chemical factors in grass carp ponds, high-throughput sequencing technology was used to analyze the eukaryotic microbial community structure in the experimental group (Bacillus added pond) and control group (ordinary pond). At the same time, the physical and chemical indicators of the two ponds were analyzed. The results showed that the contents of TN, NH₄⁺-N and NO₃^--N in the pond water of the experimental group were significantly lower than those in the control group in August and September(P<0.05). The results showed that the abundance of Cyclotella meneghiniana, Trichosporon, Chroomonas, Hedriocystis and Cyclotella in the pond water of the experimental group was significantly higher than that in the control pond(P<0.05). The Chao1 index and Shannon index of the eukaryotic microbes in the experimental group were significantly higher than those in the control group (P<0.05). The experimental results confirmed that by adding Bacillus to the pond, the structure of the eukaryotic microbial community in the water body could be changed, thereby realizing the adjustment of the physical and chemical factors of the pond. The research results could provide some theoretical support for reducing the pollution of tailwater tailwater to the water environment.

Abstract:This study was designed to compare the reproductive performance, embryonic color and biochemical composition of the wild female E. sinensis broodstock between the Yangtze and Minjiang populations. The results showed that: (1) There was no significant differences on egg production, fecundity, reproductive effort, individual egg wet weight and dry weight produced by wild female crabs between the Yangtze river and Minjiang river populations (P>0.05), but wild Yangtze river population had the significantly higher egg diameter than the Minjiang river population (P<0.05); (2) There was no significant difference in the parameters of lightness (L^*), redness (a^*), yellowness (b^*) and color differences (dE^*) (P>0.05); the total carotenoid contents in the eggs were 0.44 and 0.47 mg/g for Yangtze and Minjiang populations, respectively, and there was no significant difference between them; (3) The eggs had the close levels of moisture, crude protein and crude fat between two populations (P>0.05); C16∶0, C18∶0, C16∶1n7, C18∶1n9, C18∶1n7, C18∶2n6, C20∶4n6, C20∶5n3 and C22∶6n3 are the major types of fatty acids in the embryo, and their percentage were more than 4% of total fatty acids. The wild Yangtze population had the significantly higher of C18∶2n6 than the Minjiang population. In conclusion, wild Yangtze and Minjiang populations had the similar reproductive performance and biochemical composition in their eggs, and further researches should be focused on the evaluation of their culture performance and genetic diversity between the two populations.

Abstract:The study was conducted to compare hepatosomatic index (HSI), gonadosomatic index (GSI) in wild adult Chinese mitten crab (Eriocheir sinensis) during their catadromous migration, which were sampled from freshwater region near Zhenjiang city (defined as freshwater group) and brackish water area near Chongming Island in the estuary of Yangtze River(defined as brackish water group). After the dissection and biochemical analysis, total lipids and fatty acid composition in the hepatopancreas and muscle were further compared between the two groups. The results showed that: (1) The HSI of the males and the GSI of the females in the freshwater group were significantly higher than those of the corresponding brackish water group (P< 0.05); despite of males or females, the freshwater group had the significantly higher total lipids in the hepatopancreas than the brackish water group (P< 0.05), and there was no significant difference in total lipids in the muscle between the two groups (P> 0.05); (2) As for the hepatopancreatic fatty acid compositions, both male and female crabs from the freshwater group had the significantly higher levels of C20:1n9, C18:2n6 and C18:3n3, but the lower percentages of C18:1n7, C20:5n3 and C22:5n3 in the hepatopancreas than the brackish water group,which resulted in the fact that the freshwater group had the significantly lower levels of total n-3 polyunsaturated fatty acids (∑n-3 PUFA) and the ratio of ∑n-3 PUFA/ total n-6 polyunsaturated fatty acids (∑n-6 PUFA), but the higher ∑n-6 PUFA levels in the hepatopancreas than the brackish water group (P< 0.05); (3) As for the fatty acid compositions in the muscle, the males from freshwater group had significantly higher levels of C17:0, C18:0, C20:1n9, C18:2n6, C18:3n3 and C20:2n6, but lower percentages of C16:1n7, C20:5n3 and C22:5n3 than that of the brackish water group; thus the males from brackish water group had higher percentages of ∑n-3 PUFA and the ratio of ∑n-3 PUFA/ ∑n-6 PUFA than males from freshwater group (P< 0.05);The changing patterns of female fatty acid profiles in the two groups were consistent with those in the males, but the levels of C17:1n7 and C20:4n6 in female muscle of the freshwater group were significantly higher than those of brackish water group (P<0.05). In conclusion, when the wild adult E. sinensis migrated from freshwater area to the brackish water area in the estuary of Yangtze River, the significant decreases were found in HSI and total lipids in the hepatopancreas, but the crabs sampled from brackish water generally had the higher percentage of the total n-3-long chain PUFA (∑n-3-LC-PUFA,≥C20:2n) in the hepatopancreas and muscles than the freshwater group.

Abstract:The Integrated Multi-Trophic Aquaculture system was established in the low-salinity closed waters of Jinshan, Shanghai for the first time, and the ecological fish culture experiment and nutrient detection analysis of large yellow croaker (Larimichthys crocea) were carried out. The results showed that after the ecological restoration by Myriophyllum spicatum and Crassostrea rivularis,the concentration of NO₃-N, NO₂-N, NH₄-N, PO₄-P and COD decreased by 58.82%, 37.50%, 55.32%, 53.85% and 45.18%, the survival rate of large yellow croaker was 94%, the specific growth rate of October was (0.22%±0.018%)/d.The condition factor, viscerosomatic index and hepatosomatic index of the ecological large yellow croaker was 1.82%±0.25%, 1.36%±0.32 %, 3.18%±0.22 %, significantly 13.7%, 25.7 %, 24.5 % lower than non-ecological large yellow croaker (P<0.05).In particular, the crude fat content of ecological large yellow croaker was 31.14%±0.11%, which was significantly lower than that of non-ecological large yellow croaker (42.46%±0.08%) (P<0.05).The water content, crude protein content and ash content of ecological culture were 66.79%±5.94 %, 3.84%±0.0029 % and 73.15% ±0.069%,which were significantly higher than non-ecological culture 54.91%±4.88 %, 3.14%±0.0046% and 65.96%±0.033 % (P<0.05).The essential amino acid valine, methionine, isoleucine, leucine, threonine, phenylalanine and lysine of ecological culture were 20.7%, 36.0%, 22.1%, 20.5%, 20.1%, 25.2%, 18.2% significantly higher than non-ecological culture (P<0.05).The above results showed that the large yellow croaker can be cultured in 5-6 low salinity waters, and the ecological cultured large yellow croaker had higher nutritional value.

Abstract:In order to evaluate nutritional value of Squaliobarbus curriculus and Cirrhinus mrigala to Sinaperca chuatsi, chemical components were determined and energy density were estimated in S. curriculus with body weight of(5.27±1.03) g,C. mrigala(5.05±1.21) g and S. chuatsi(5.19±0.92) g, to explore the feasibility of replacing C. mrigala with S. curriculus in S. chuatsi culture. The results showed that protein content of whole fish in S. curriculus and C. mrigala was significantly higher and moisture content was significantly lower than that of S. chuatsi (P<0.05). The essential amino acid indexes of the two fishes reached 92.56%±2.31% and 93.17%±0.36%), respectively. Chemical score of most essential amino acids were higher than 0.84. Fat content and energy density of S. curriculus were significantly higher than those of C. mrigala and S. chuatsi, and ash content was significantly lower than that of C. mrigala (P<0.05). It indicated that the two fishes had high nutritional value to S. chuatsi, but S. curriculus showed higher nutritional value than C. mrigala. It is feasible to use S. curriculus to replace C. mrigala in S. chuatsi culture, which provides a reference to transform culture methods in S. chuatsi.

Abstract:In this paper, we used the method of bibliometric analysis to review the documents related to the study on biological resources and ecological environment in the Yangtze River Basin of China and indexed CNKI database. We first created descriptive statistics of the number of articles published annually and the journal frequency distribution. Then, the methods of author, institution cooperation network and keyword based knowledge mapping and burst analysis were used to explore the hotspots and the recent frontiers.Descriptive statistics suggested that the number of research documents presented an increasing trend, and began to increase sharply in 2016. Authors and institutions have formed few frequent and stable cooperative relations.Most authors cooperation was limited to the researchers within the institution. The relatively active institutions cooperated among Yangtze River Scientific Research Institute, Yangtze River Water Resources Protection Bureau and Yangtze Water Resources Commission. Environmental science, regional economics, hydraulic engineering, agricultural economy are the dominant disciplines. Results of the burst analysis of the most recent document hotspots showed that the current research in biological resources and ecological environment in the Yangtze River Basin of China has four study frontiers:(1) carrying out research on ecological environment assessment and protection, urbanization and ecological civilization construction, and green development of urban agglomerations in Yangtze River Economic Zone; (2) research on ecological environment monitoring and protection, forest resources conservation, soil and water conservation and erosion, resources and ecological compensation mechanism and sustainable development of ecological environment in the Three Gorges and Three Gorges Reservoir areas; (3) Research on ecological environmental protection and planning, ecological red line, conservation of biological resources and biodiversity conservation in natural protection area of the Yangtze River Basin; (4) Under the background of the Yangtze River integrated protection program, carry out research on the protection and restoration of the aquatic biological resources, ecological environment, comprehensive management and the rational development and utilization of the aquatic biological resources; (5) Research on hydropower resources development, water environment protection and fishery eco-environment protection in the source area of Yangtze River.In order to manage and protect the important biological resources scientifically in the Yangtze River Basin,we suggest that we should establish scientific design monitoring system, and construct biological data models for fishery resources and ecosystems in the whole river basin, develop risk assessment and decision-making system for the conservation and development of fishery resources, and build scientific technological system for the proliferation and release, and develop GIS-based monitoring system for fishery resources and environment in the Yangtze River Basin.

Abstract:Because of its economic value and wide distribution, albacore tuna (Thunnus alalonga) has become one of the main fishing targets in the world’s marine fisheries. Prediction of albacore tuna can improve fishing efficiency and yield, and provide scientific basis for fishery production.The production data of albacore tuna in the Indian Ocean from 2006 to 2014 and three environmental factors of temperature, salinity and chlorophyll a concentration in the surface layer of the ocean were used in this study. The single-factor Suitability Index (SI) of Indian Ocean albacore tuna with various environmental factors was established monthly by using the single-variable non-linear index model. Then the arithmetic average method was used to obtain the comprehensive Habitat Suitability Index (HSI) model. Using the 2016 Indian ocean albacore tuna production data and the corresponding marine environment data, furthermore, the HSI model was verified based on the ArcGIS platform. The results show that the accuracy of the monthly fishing ground forecast is about 90.56% and the overall forecast accuracy for each HSI grade is 87.46%. Moreover, for the central fishing ground with I_HSI>0.5, the average accuracy rate is 71.82%. Considering that the average yield ratio of I_HSI>0.5 is 69.35%, it can be concluded that the established HSI model had a promising forecast effect for the Indian Ocean albacore tuna.

Abstract:To study the influence mechanism of marine environmental factors on the potential fishing ground for Pacific saury in Northwestern Pacific, by using the fishery statistics data of Chinese Pacific saury fishing boats from 2013 to 2014 and the marine environment data of NOAA website, this paper set up MAXENT models: the accuracy of the MAXENT model was verified by using receiver operating characteristic(ROC) curve, the importance of oceanographic environmental factors was evaluated by Jackknife Method, the potential fishing area distribution map of the Pacific saury was made by Arcgis. The results show that MAXENT model was proved to be accurate and reliable: during the Pacific saury’s best fishing period from August to October, the potential fishing ground mostly occurred around the eastern waters of Hokkaido and Kuril islands .The fishing ground distribution for Pacific saury is influenced by SST mostly among several environmental factors, of which the average percentage contribution to the model is 64.3%,in the meantime, the average contribution percentage of chlorophyll (Chl.a) and slinity (SSS)are 20.6%, 15.2% respectively.In August and September, chlorophyll (Chl.a) holds a higher model contribution to the distribution of the Pacific saury than salinity (SSS),whereas, the effect of chlorophyll (Chl.a) on the distribution of Pacific saury in October was lower than salinity (SSS).

Abstract:As one of the hard tissues of fish, eye lens has the characteristics of stable structure, resistance to erosion, and easily accessible. It contains a large amount of protein, which records much chemical information, and has been applied to a certain extent in the age determination of fish. In recent years, with the continuous innovation and progress of geobiochemical technology, the trace element and stable isotope information of fish eye lens has been paid more and more attention to by scholars at home and abroad. Here, the application of determined age, habitat reconstruction and feeding ecological tracking were reviewed in terms of the diameter and weight, microstructure, trace elements and stable isotope of the eye lens, after analyzing the composition and growth pattern of fish eye lens and comparing the advantages of eye lens and other tissues for stable isotope analysis, the research methods, application status and development prospects for stable isotope of eye lens in fish life history information, especially in feeding ecological tracking and habitat reconstruction were summarizied to provide reference for future research.

Abstract:The development of recreational fishery is an important part of promoting modern fishery construction, and an important measure to implement the rural revitalization strategy and the marine economy construction. Based on the literature sample data of the world’s leisure fisheries related research topics in the Web of Science database from 1966 to 2018, this paper uses CiteSpace measurement software to systematically sort out the international leisure fishery through literature citation analysis, keyword co-occurrence and sudden word detection. Research frontiers and hotspots show that: (1) The knowledge structure of international leisure fishery research is based on biology, resource science and environmental science. At the same time, the research frontier of international leisure fishery has gradually turned to the integrity of society-ecosystem and sustainable development in the past 10 years; (2) Recreational fishery is a typical composite interdisciplinary subject. Interdisciplinary comprehensive research is an important guarantee for its disciplinary development. The development of international recreational fisheries has formed a relatively complete research relying on multidisciplinary integration; (3) New technical methods such as big data technology, 3S technology, simulation technology and complex system models are widely used in the recreational fisheries, which will provide efficient and accurate technical support to solve comprehensive, dynamic and systematic problems. Finally, the study suggests that the domestic research on recreational fisheries should focus on the multi-scale nature of the research area, the integration of interdisciplinary disciplines and the attention to environmental issues in the development process of recreational fisheries in the future.

Abstract:The organized and large-scale management of small-scale fisheries is the international trend of small-scale fisheries management. Based on rural revitalization strategy, the decentralization of government of small-scale fisheries management power to small-scale fisheries cooperatives and realization of small-scale fishery cooperatives self-governance are of great practical significance to develop Chinese small-scale fisheries self-governance cooperatives. It is the key to solve the problems of low efficiency, high cost and poor performance in the management of small-scale fisheries in China. Through field surveys of Chinese and Japanese small-scale fishery cooperatives, self-governance theory,learning from the analysis of Japanese small-scale fishery self-governance cooperatives and the enlightenment to development of small-scale fishery self-governance cooperatives in China, this paper points out the problems of lack of self-governance, imperfect organizational structure, unregulated operation, the lack of endogenous motivation, passive regulation, crisis of trust with the lack of cooperation in the role of cooperatives and insufficient social incentives with the lack of reward and punishment mechanism. At last, it is suggested that the development of small-scale fishery self-governance cooperatives should give them the power to manage fisheries, innovative fisheries management systems, improvement of organizational structure, strict operation in accordance with the cooperatives charter, enhancement of trust mechanisms and social incentives and so on.

Abstract:An intracellular endo-cellulase was isolated and purified from the fermentation of Aspergillus niveus MA35 in the gut of Megalobrama amblycephala. The enzyme was purified sequentially by Q-Sepharose Fast Flow chromatography and Sephadex G-100 gel chromatography. The specific activity of the purified endoglucanase increased to 30.6 U/mg from 22.3 U/mg of the crude endoglucanase. The molecular masses of the enzyme was determined by SDS-PAGE to be about 45 ku. The optimum temperature is 45 ℃ and the optimum pH is 4.5. The enzyme has good stability between pH 4.0-8.0 and 30-55 ℃. Zn²⁺ and Mn²⁺ have an activation effect on enzymes. Mg²⁺, Cu²⁺, Fe²⁺, Cd²⁺ and Co²⁺ have inhibitory effects on enzyme activities, among which Mg²⁺, Cu²⁺ and Fe²⁺ have strong inhibitory effects, and Na⁺, K⁺ and Ca²⁺ have little effect on enzymes.