Abstract:This paper reviews the process of fish genomic research in China, which started with scratch and then developed from small to large. The important progress and findings regarding BAC library construction, high-density genetic linkage map construction, genome sequencing and fine mapping, genome selection and genome editing by Chinese scientists were introduced. Based on the comparison with the international progress in this field, it was pointed out that Chinese scientists followed the international research from 2008 to 2013.While from 2014 to 2018, China's fish genomic study has accelerated development and has been catching up. Just during the past five years, the top journals Nature and Nature Genetics have published several papers of genome sequencing and fine mapping in important aquatic fishes from China, such as half-smooth tongue sole, common carp, grass carp, Japanese flounder and sea horse. The progress has brought China's fish genomic research from full-scale following in the past to the present coexistence of following, running side-by-side, and even leading in some research directions and species. In the meanwhile, we summarized the current shortcomings and problems in fish genomic research and application field, and prospected the future development of aquatic genomic research in China.

Abstract:In this paper, the development and application of related technologies in aquatic genome research are reviewed. Taking the appearance of the next-generation sequencing (NGS) technology as a demarcation point, we firstly looked back to the researches of genetics and molecular biology of aquatic organisms in the early stages, and the basic researches for the whole-genome sequencing. And then we emphatically introduced the development of the NGS technology application for whole-genome sequencing and economic traits analysis. At last, the development trend of aquatic organisms whole-genome researches is prospected. The genetic mechanism of economic traits of aquatic organisms is highly complex, thus there are still a lot of difficulties in explaining the genetic mechanism at the whole-genome level. However, it is a basic law that trait is determined by genes, so the exploration will still be fascinating.

Abstract:This paper introduces the development of molecular marker-assisted breeding technology for aquatic species. Detecting markers linked to economic traits is the basis of molecular marker-assisted breeding. Therefore, this article focuses on the advances in genes or markers acquisition technology, explores the complexity of the relationship between genes or markers and traits, discusses the difficulty of accurately identifying genes or markers closely linked to economic traits, and points out that the difficulty is mainly due to the very complex influence of the genome on the formation of traits. In the past ten years, a number of varieties bred by molecular marker-assisted breeding technology have been applied in aquaculture, indicating that this new technology has played a positive role in promoting industrial technological progress. At the same time, the deficiencies of molecular marker-assisted breeding including genome-wide selection are caused by the extremely complicated and variable formation mechanism of fish trait, determining the characteristics of developmental stage theory.

Abstract:Dendritic cells (DCs) are currently the most powerful antigen-presenting cells in vivo and the only ones that can activate the initial T lymphocyte reaction. It plays an important role in innate immunity, adaptive immunity and maintenance of autoimmune tolerance, so it has always been an important area of immunological research. This paper briefly reviews the types of DCs and its function in animals and the cellular markers of various DCs. It summarizes separation, purification method and the method of morphological observation of DCs in fish. Results show that the dendritic cells of fish have many of the hallmarks of mammalian DCs including the ability to phagocytose small particles, stimulate T cell proliferation, induce CD4⁺ T cell activation, and the expression of dendritic cell markers, activation by Toll like receptor-ligands, and the ability to migrate in vivo and stimulate a mixed lymphocyte reaction; the molecular markers of DCs in different fishes are not exactly the same; DCs in fish were found in various organs including head kidney, kidney, gill, skin, thymus, spleen and intestine. Although some progress has been made in the research of DCs in fish, there are still many important problems to be solved:① there are currently no cellular markers for DCs in fish, so strengthening the research in this field is useful to enhance the research level of DCs' isolation, distribution in vivo and function. ② It is necessary to intensify and improve the technique of isolation and culture of DCs in fish and to master the methods of isolation and culture of various DCs. ③ Enhancing the research of DCs in antigen-presentation in fish has important theoretical significance for further research of immune mechanism and rational design and application of vaccine.

Abstract:In the past decade, the system of national aquatic germplasm reserves was constructed in China, and over 500 national aquatic germplasm reserves were established in different water type areas. In order to optimize reserve management, we analyzed the distribution pattern of national aquatic germplasm reserves within the water type geographical distribution and key protected species. The following general problems occurred during the construction and management of the reserves. 1) The water type pattern of these reserves was not fully reasonable. The number of inland water reserves were far more than sea reserves, while the mean area of inland water reserves were obviously smaller than sea reserves. 2) There were too few reserves in some basins so that the deficiencies for protecting species occurred, such as some rivers in Southwestern China and Southern China. 3) It was lack of systematic investigation to ensure the list of key protected species. Pelteobagrus fulvidraco was listed as key protected species in 70 reserves, while there were 69 national protected aquatic species excluded from the key protected species list. We should develop a comprehensive plan for aquatic germplasm reserve construction and management, based on a systematic investigation and research, in order to realize the protection and sustainable utilization of aquatic germplasm resources.

Abstract:In recent years, overfishing, pollution and unsustainable coastal development have caused irreversible damage to habitat, ecosystem functions and biodiversity. Moreover, several problems such as transformation and upgrading of tradition fishery and culture industries, environmental pollution, declining of fishery resources, small-scale fisheries under threat have come into notice in recent years, attracting more and more scientists to study related fields. The related framework to solve above problems is most remarkable for the "blue growth"projects proposed by FAO and"marine ranching"proposed by China. Both"blue growth"and"marine ranching"frameworks are promoting the sustainable use and conservation of renewable resources on global and regional scale. However, under new circumstances, with the evolution of new framework, new trends in the evolution of environmental integrity and technical feasibility should come into being. In this paper, we discussed the central target, work and potential problems of marine ranching construction. Thus, we summarized the main current techniques of"blue growth"and"marine ranching"framework, integrated the relative techniques and framework of urban ecology, and proposed marine livestock ecological urbanization hypothesis-based marine ranching technical procedures. It entails marine livestock ecological urbanization hypothesis-based marine ranching sites selection and design, habitat construction, enhancement and behavioral control of marine biological resource and management technical procedures. Finally, we analysed the practical applicability of both relative techniques and technical procedure integration. The above framework and specific technical procedures are proving especially useful and posses reference significance in regard to scientific and practical applicability of marine ranching construction.

Abstract:The "Blue Granary" is of great significance for safeguarding food security, promoting economic development, culturing emerging industries, highlighting national rights, improving the ecological environment, and breaking through industrial bottlenecks. In the current technological and industrial situation, how to construct the "Blue Granary" effectively has become a hot topic. Here we elaborated the definition, particularity, necessity and feasibility of "Blue Granary" construction in a systematic and deep-going way. We suggested that the construction of "Blue Granary" should help to realize the transformation from a big industrial country to a strong one and to achieve the goal of improving the ability of scientific and technological innovation. What's more, the implementation approaches have been proposed from the following aspects:focusing on major needs, constructing the value chain of scientific and technological advances; adhering to the original drive, making breakthrough at important scientific issues; strengthening integrated demonstration, supporting the healthy and sustainable development of the industry. Specifically, we should commit to the general principle of ensuring ecological priority and coordination of land and sea integrated development plans in accordance with the requirements of basic research, major common key technologies, and typical application demonstrations of the entire chain. Then, we continued to take four major measures including seed breeding drive, technology upgradation, space expansion, and industrial demonstration, in order to meet the industrial demands, namely germplasm creation, healthy aquaculture, resources conservation, friendly fishing, and circulation processing. In the meanwhile, we need to build three systems of smart farming, intelligent fishing and green processing, and to accomplish two goals of high-quality protein supply and industrial transformation and upgrading, all of which eventually will make contributions to construct a blue granary with Chinese characteristics.

Abstract:Driven by economic factor, China's aquaculture expands and intensifies rapidly, meanwhile, the restrictions of land, fresh water and fishmeal to aquaculture development have become increasingly obvious, N and P emission, carbon footprint and ecological footprint of aquaculture systems are increasing significantly. Therefore, development pattern of China's aquaculture needs to be remoulded in a way of ecological intensification. From the multidimensional and sustainable development perspectives,it can be inferred that, large inland waters (lakes and reservoirs) in China are suitable only for aquaculture without feeding; coastal maricultures (sheltered waters or shallow waters, <10 m in depth and <2 km from the coast) are suitable only for extractive species farming; offshore maricultures (10-50 m in depth, >2 km from the coast) can develop various maricultures combined with sea ranching; far offshore mariculture (>50 m in depth, high sea or EEZ) for fish farming with steel frame cages or vessels will have a bright future. There is a long way to go for the ecological intensification of pond aquaculture and for reconstructing recirculating aquaculture systems to industrialized solar aquaculture systems.

Abstract:Industrial biotechnology aims at transforming discoveries of life science into products, processes, systems, and services, which creates new opportunities for economic developments and is regarded as an important research field worldwide. Fermentation engineering is a key field of industrial biotechnology, which is rebuilding fermentation and light industry. In this paper, we systematically summarized four innovation tasks of fermentation engineering, including transformation and upgrading of bulk fermented products, energy conservation and emission reduction of traditional industries, solving safety issues of food processing, and biomanufacturing of functional nutraceuticals. Finally, development trends in fermentation engineering were discussed. The future development of fermentation engineering will be facilitated by technology and equipment systems for fermentation intelligentization and new industrial mode based on fermentation intelligentization.

Abstract:Fisheries management has always been a problem facing all fisheries countries worldwide.This article first analyzes the features of the fisheries in China, and points out that our country's fisheries management tends to be more complex and difficult than any other country in the world. It goes on to describe the history of the China's fisheries management and the development process of China's fisheries policies, indicating the role of fisheries policies in guiding and promoting the industrial production during the whole development process. With Fisheries Law of the People's Republic of China as the basic framework, China is thought to have initially formed a fisheries management system with a complete structure and powerful measures for constant improvement and reinforcement. By introducing main theories in fisheries management and reviewing principal literature on fisheries management studies conducted by Chinese scholars, the article highlights aquaculture management both as the focus of China's fisheries management and as the core research field of fisheries management in future. Major regimes and measures of China's fisheries management are summarized, with their corresponding effects being evaluated to a certain extent. China's continuous introduction of advanced fisheries management philosophies over the past several decades, especially since the reform and opening up, plays an active role in securing the prosperity of the following five industries:aquaculture, fishing, processing and logistics, enhancement, and recreational fisheries; greater efforts are being made in fisheries ecological environment restoration; the capacity of law-based governance in fisheries has been significantly improved. However, due to the characteristics of China's fisheries as well as the complex and uncertain nature of fisheries itself, certain prominent problems still remain in the country's fisheries industry. With reference to relevant fisheries development planning, the article concludes with a prospect that China's fisheries management will be steered towards the total catch control of fisheries resources and the intensification of conservation and ecological restoration of fisheries resources.

Abstract:Singapore is a small island country with limited land for agricultural purposes and restricted sea waters available for fish farming. However, the ornamental fish industry of Singapore is quite unique and successful, being the world No. 1 exporter of ornamental fish, selling over 1 000 fish species to over 80 countries and generating an annual revenue of USD 43 million in 2016. Its success is mainly thanks to its specific capabilities in licensing, biosecurity controls, culturing, packing, transporting and disease control. Efforts are being made to breed and domesticate many of the high-value marine species and new freshwater species and to develop novel reciculating culture systems. Upstream research has focused on developing and using genomic tools to breed new varieties and to maintain genetic diversity in the wild. However, due to limited space for culturing fish and strong competitions from neighbouring countries, Singapore's ornamental fish industry is facing many challenges, and its market share is reducing. In this review, we will summarize the status and development of Singapore's ornamental fish industry, discuss its challenges and make some suggestions for maintaining the leading position of the industry.

Abstract:Beta-oxidation is a main pathway of fatty acid catabolism. Although this pathway has been studied for almost half a century in mammals, lots of metabolic details and the related regulatory mechanisms are still unknown in fish. With the rapid development of aquaculture industry, more and more attention is being paid to fish fatty acid β-oxidation, not only because it could help to promote dietary lipid utilization as an alternative energy source for protein, but also it could help to alleviate the severe fat accumulation in farmed fish. In this review paper, we systemically review the research progress of fatty acid β-oxidation in fish. As in mammals, fish fatty acid β-oxidation occurs in mitochondria and peroxisome. In most of fishes, mitochondrial β-oxidation is the main contributor of total fatty acid β-oxidation. Nevertheless, the activity of fatty acid β-oxidation differs from different fish tissues, and in general, the activity of peroxisomal fatty acid β-oxidation in liver is much higher than that in other tissues. Moreover, mitochondrial and peroxisomal β-oxidation has different substrate preference. Peroxisome prefers to oxidize the fatty acids containing more than 18 carbons, while mitochondria prefer to oxidize the fatty acids containing no more than 18 carbons. In fish fatty acid β-oxidation, carnitine palmitoyl transferase (CPT-1) is the speed-limited enzyme and plays key roles in transferring fatty acid from cellular matrix into mitochondria. Fish fatty acid β-oxidation could be regulated by hormone, nuclear receptors (for example peroxisome proliferator-activated receptor, PPAR) and microRNA, and so on. Recently, the mechanisms of PPARα activation and related metabolic regulation have been revealed in Nile tilapia. The activated PPARα could stimulate proliferation of mitochondria and activity of mitochondrial fatty acid β-oxidation, and cause decrease of liver lipid content. In fish, fatty acid β-oxidation is also affected by physiological factors (such as age and body weight), nutritional status (fed and fasting), dietary factors (dietary lipid sources and levers, and some dietary additives, such as L-carnitine) and some environmental pollutants. Among them, dietary lipid content and sources could significantly affect efficiency of fatty acid β-oxidation. In fact, the impaired fatty acid β-oxidation is an important cause or consequence of high energy diet-induced metabolic diseases in fish. Recently, more and more dietary additives, which target on fatty acid β-oxidation, have been widely used. Among these dietary additives, L-carnitine has been intensively studied and the related studies show that L-carnitine could improve fatty acid β-oxidation through increasing transferring efficiency of fatty acids as substrate from cellular matrix into mitochondria for further fatty acid β-oxidation. Moreover, some vitamins, such as V_C and V_D have also been demonstrated to play positive roles through regulating fatty acid β-oxidation-related enzymes or genes. All in all, fatty acid β-oxidation is essential in fish metabolism and energy homeostasis, and more studies are necessary in future fish nutrition studies.

Abstract:The microbiota plays a major role in the health and disease in animals, including maintaining health of the gut, promoting development of epithelium cells, resisting the intrusion of pathogenic bacteria, regulating the absorption harvest of energy and metabolism of lipid. It is a great challenge to the fish gut microbiota research due to the complicated factors, such as differences of fish species, feeding habits or survival environment. Based on the previous related researches, the present article first reviewed the gut microbiota composition of different fishes. Also, the effects of different factors on the gut microbiota of fish were reviewed, such as feed component, water chemical factors, fish species, genotype, developmental stages, aquaculture models and strategies of feeding. Finally, some present issues and future research directions about the fish microbiota were presented.

Abstract:Cryptocaryon irritans is an important parasite in mariculture fish, which can infect almost all kinds of marine bony fishes, causing fatal diseases and huge economic losses to marine aquaculture in China. Due to the property of living in the epidermis of the skin and gills, this makes it as good model to study the mucosal immunity of seawater fish, which are conducive to developing effective vaccine. In this paper, we reviewed the current progress of grouper (Epinephelus coioides) anti-C. irrians infection, which will provide the theoretical support for carrying out the immune prevention and control measures against C. irritans. The existing results show that after C. irritans infection, grouper skin mucous or its culture supernatant can immobilize the theronts, and specific IgM antibody anti-C. irritans was detected, which is produced by the antibody secreting cells in the skin and plays an important role in resistance to parasitic infections; We found many immune cells such as NCC cells, neutrophil cells around the parasites; meanwhile, the expression levels of some chemokines and chemokine receptors were significantly increased in the infection sites, implying that these immune cells may also involve resistance to parasite infection; In addition, we found that rabbitfish (Siganus oramin) was naturally resistant to C. irritans infection, the serum and skin mucous of which could kill the theronts and tomont of C. irritans. Next, a novel protein that is lethal to C. irritans was isolated from the serum of rabbitfish and which was identified as L-amino acid oxidase. Finally, by immune experiment, we proved the feasibility of vaccines for prevention and control of cryptocaryoniasis.

Abstract:This review briefly introduced representative research results on the aquatic animal virology in China during the past several decades, including fish viruses, shrimp viruses, amphibian and reptile viruses and so on. Moreover, current trends in development of aquatic animal virology were further discussed. It can help to improve comprehensive understanding of the current state and development of the aquatic animal virology studies.

Abstract:Our country is rich in aquatic resource. The fishery industry in China has developed rapidly and it led to the great amount of by-product-remnants. Because of the high content of protein, the active peptides could be prepared by enzymatic hydrolysis to be utilized. The proper utilization of by-products is very significant as it can reduce the waste of aquatic resources, improve the additional value, lower the cost and increase the economic benefit. In this paper, the sources of antioxidant peptides from by-products of aquatic product, isolation of antioxidant peptides, detection of antioxidant activity and antioxidant mechanism were summarized.

Abstract:With the improvement of living standards, people have put forward higher requirements for the quality of aquatic products, so it is imperative to develop new processing technologies. Freeze-dried foods cater to this development trend because of their excellent nutritional quality, easy logistics, transportation, and storage and convenient consumption. In this paper, the pretreatment process in the vacuum freeze-drying process of aquatic products (slicing treatment, ultrasonic treatment, immersion treatment, coating treatment, etc.), freeze-drying process parameters (pre-freezing process parameters, drying conditions, etc.), quality changes (sensory, texture, nutrition, flavor, taste, rehydration) and quality prediction model research status were reviewed. The future research and development trend of aquatic product vacuum freeze-drying technology was also focused on. It will provide reference for the research and application of vacuum freeze-drying products.