ABSTRACT
Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.
Subject(s)
Aquaculture , Ecosystem , Environmental Monitoring , Seafood , Sustainable Development , Animals , Aquaculture/trends , Climate Change , Diet , Ecology , Environmental Policy , Fisheries , Food Supply/methods , Greenhouse Gases , Humans , Mollusca , Nitrogen , Phosphorus , Seafood/supply & distribution , Seaweed , Sustainable Development/trendsABSTRACT
The production of aquatic animals has more than doubled over the last 50 years and is anticipated to continually increase. While fish are recognized as a valuable and sustainable source of nutrition, particularly in the context of human population growth and climate change, the rapid expansion of aquaculture coincides with the emergence of highly pathogenic viruses that often spread globally through aquacultural practices. Here, we provide an overview of the fish virome and its relevance for disease emergence, with a focus on the insights gained through metagenomic sequencing, noting potential areas for future study. In particular, we describe the diversity and evolution of fish viruses, for which the majority have no known disease associations, and demonstrate how viruses emerge in fish populations, most notably at an expanding domestic-wild interface. We also show how wild fish are a powerful and tractable model system to study virus ecology and evolution more broadly and can be used to identify the major factors that shape vertebrate viromes. Central to this is a process of virus-host co-divergence that proceeds over many millions of years, combined with ongoing cross-species virus transmission.
Subject(s)
Evolution, Molecular , Fish Diseases , Fishes , Viruses , Animals , Aquaculture/trends , Fish Diseases/transmission , Fish Diseases/virology , Fishes/classification , Fishes/virology , Genetic Variation , Metagenomics , Phylogeny , Virome/genetics , Virus Diseases/transmission , Virus Diseases/veterinary , Virus Diseases/virology , Viruses/genetics , Viruses/classificationSubject(s)
Aquaculture , Carbon Sequestration , Ecology , Ostreidae , Shellfish , Animals , Earth, Planet , Aquaculture/methods , Aquaculture/trends , Global Warming/prevention & control , Ecology/methodsABSTRACT
The use of probiotics in aquaculture is widely recognized as an ecological and cost-effective approach to raising healthy, pathogen-tolerant aquatic animals, including fish and shrimp. In particular for shrimp, probiotics are viewed as a promising countermeasure to the recent severe damage to the shrimp industry by bacterial and viral pathogens. Purple non-sulfur bacteria (PNSB) are Gram-negative, non-pathogenic bacteria with wide application potential in agriculture, wastewater treatment, and bioenergy/biomaterials production. In aquaculture, lactic bacteria and Bacillus are the major probiotic bacteria used, but PNSB, like Rhodopseudomonas and Rhodobacter, are also used. In this review, we summarize the previous work on the use of PNSB in aquaculture, overview the previous studies on the stimulation of innate immunity of shrimp by various probiotic microorganisms, and also share our results in the probiotic performance of Rhodovulum sulfidophilum KKMI01, a marine PNSB, which showed a superior effect in promotion of growth and stimulation of immunity in shrimp at a quite low concentration of 1 × 103 cfu (colony forming unit)/ml in rearing water.
Subject(s)
Aquaculture , Probiotics , Rhodospirillaceae , Aquaculture/methods , Aquaculture/trends , Rhodospirillaceae/physiology , Probiotics/standards , Penaeidae/immunology , Penaeidae/microbiology , Adjuvants, Immunologic , AnimalsSubject(s)
Aquaculture/trends , Seafood/supply & distribution , Sustainable Development/trends , Animal Feed , Animals , Aquaculture/statistics & numerical data , Bivalvia , Climate Change , Fatty Acids, Omega-3/metabolism , Fisheries/statistics & numerical data , Humans , Salmon , Sea Cucumbers , Seaweed , WashingtonABSTRACT
Gene editing offers opportunities to solve fish farming sustainability issues that presently hampers expansion of the aquaculture industry. In for example Atlantic salmon farming, there are now two major bottlenecks limiting the expansion of the industry. One is the genetic impact of escaped farmed salmon on wild populations, which is considered the most long-term negative effect on the environment. Secondly and the utmost acute problem is the fish parasite salmon lice, which is currently causing high lethality in wild salmonids due to high concentrations of the parasite in the sea owing to sea cage salmon farming. There are also sustainability issues associated with increased use of vegetable-based ingredients as replacements for marine products in fish feed. This transition comes at the expense of the omega-3 content both in fish feed and the fish filet of the farmed fish. Reduced fish welfare represents another obstacle, and robust farmed fish is needed to avoid negative stress associated phenotypes such as cataract, bone and fin deformities, precocious maturity and higher disease susceptibility. Gene editing could solve some of these problems as genetic traits can be altered positively to reach phenotype of interest such as for example disease resistance and increased omega-3 production.
Subject(s)
Aquaculture/trends , Disease Resistance/genetics , Gene Editing/methods , Salmo salar/genetics , Animals , Fisheries , Humans , Phenotype , Salmo salar/growth & developmentABSTRACT
The growing interest in laver as a food product and as a source of substances beneficial to health has led to global consumer demand for laver produced in a limited area of northeastern Asia. Here we review research into the benefits of laver consumption and discuss future perspectives on the improvement of laver product quality. Variation in nutritional/functional values among product types (raw and processed (dried, roasted, or seasoned) laver) makes product-specific nutritional analysis a prerequisite for accurate prediction of health benefits. The effects of drying, roasting, and seasoning on the contents of both beneficial and harmful substances highlight the importance of managing laver processing conditions. Most research into health benefits has focused on substances present at high concentrations in laver (porphyran, Vitamin B12, taurine), with assessment of the expected effects of laver consumption. Mitigation of chemical/microbiological risks and the adoption of novel technologies to exploit under-reported biochemical characteristics of lavers are suggested as key strategies for the further improvement of laver product quality. Comprehensive analysis of the literature regarding laver as a food product and as a source of biomedical compounds highlights the possibilities and challenges for application of laver products.
Subject(s)
Food Handling/standards , Porphyra/chemistry , Quality Control , Seaweed/chemistry , Aquaculture/trends , Desiccation , Food , Porphyra/microbiology , Seaweed/microbiology , VegetablesABSTRACT
Aquaculture will continue to grow, but environmental constraints will interact with changing consumer profiles and regulatory frameworks such that future growth will look somewhat different from the trajectories of the past 30 years. Availability and price of land, fresh water, feeds and energy, and concerns about pollution and the introduction of non-native species will be major constraints to expansion. New technology will evolve in response to these concerns. This new technology will be based on the principle of sustainable intensification so as to reduce the environmental footprint per unit of production and limit volatility in markets precipitated by disease and other production system problems. Markets and consumer demand will be reflected in the economics of the industry under more sophisticated regulatory regimes. More sustainable sources of the proteins and oils in fish diets, improved genetic management, and better health and production systems will continue to underpin the expansion of aquaculture into the 21st century and beyond.
La croissance de l'aquaculture va se poursuivre mais les contraintes environnementales risquent d'interagir avec les mutations des profils des consommateurs et avec l'évolution des cadres réglementaires, de sorte que cette croissance empruntera à l'avenir des voies bien différentes de celles tracées au cours des 30 dernières années. Les principaux obstacles à la croissance concernent la disponibilité et le prix des terres, de l'eau douce, des aliments pour animaux et de l'énergie, les problèmes en lien avec la pollution et l'introduction d'espèces non natives. L'évolution des nouvelles technologies devrait apporter une réponse à ces préoccupations. Ces nouvelles technologies reposeront sur le principe d'une intensification durable de la production afin de réduire l'empreinte écologique par unité de production et de limiter la volatilité accélérée des marchés induite par les maladies ou par d'autres problèmes affectant les systèmes de production. Les exigences des marchés et des consommateurs se répercuteront dans la stratégie économique du secteur en vertu de dispositifs réglementaires plus sophistiqués. Grâce au recours à des sources plus durables de protéines et d'huiles pour l'alimentation des poissons, à une meilleure gestion des ressources génétiques et à des systèmes sanitaires et de production plus performants, l'expansion de l'aquaculture devrait se poursuivre tout au long du xxie siècle et au-delà.
Aunque en el futuro la acuicultura seguirá creciendo, las limitaciones ambientales interactuarán del tal modo con la evolución de las modalidades de consumo y los ordenamientos reglamentarios que este crecimiento se apartará en cierta medida de las trayectorias observadas en los últimos 30 años. La disponibilidad y el precio de terrenos, agua dulce, piensos y energía, junto con las inquietudes por la contaminación y la introducción de especies no autóctonas, limitarán considerablemente la expansión. En respuesta a esas inquietudes surgirá una nueva tecnología basada en el principio de la intensificación sostenible, que servirá para reducir la «huella¼ ecológica por unidad de producción y para poner coto a la volatilidad de los mercados causada por enfermedades u otros problemas del sistema productivo. La demanda de mercados y consumidores incidirá en la economía del sector en forma de ordenamientos reglamentarios más sofisticados. En los primeros compases del siglo XXI, y también más adelante, la expansión de la acuicultura seguirá reposando en el uso de fuentes más sostenibles de proteínas y aceites para alimentar a los peces, en el perfeccionamiento de los procesos de selección genética y en sistemas productivos y sanitarios más eficaces.
Subject(s)
Animal Feed , Aquaculture , Fish Diseases/prevention & control , Fishes , Animals , Aquaculture/trends , Commerce , Diet , Environmental PollutionABSTRACT
The global expansion in aquaculture production implies an emerging need of suitable and sustainable protein sources. Currently, the fish feed industry is dependent on high-quality protein sources of marine and plant origin. Yeast derived from processing of low-value and non-food lignocellulosic biomass is a potential sustainable source of protein in fish diets. Following enzymatic hydrolysis, the hexose and pentose sugars of lignocellulosic substrates and supplementary nutrients can be converted into protein-rich yeast biomass by fermentation. Studies have shown that yeasts such as Saccharomyces cerevisiae, Candida utilis and Kluyveromyces marxianus have favourable amino acid composition and excellent properties as protein sources in diets for fish, including carnivorous species such as Atlantic salmon and rainbow trout. Suitable downstream processing of the biomass to disrupt cell walls is required to secure high nutrient digestibility. A number of studies have shown various immunological and health benefits from feeding fish low levels of yeast and yeast-derived cell wall fractions. This review summarises current literature on the potential of yeast from lignocellulosic biomass as an alternative protein source for the aquaculture industry. It is concluded that further research and development within yeast production can be important to secure the future sustainability and economic viability of intensive aquaculture. © 2016 Society of Chemical Industry.
Subject(s)
Animal Feed/analysis , Aquaculture , Fishes/growth & development , Food Supply , Fungal Proteins/administration & dosage , Global Health , Yeasts/isolation & purification , Amino Acids/analysis , Animal Feed/economics , Animals , Aquaculture/economics , Aquaculture/trends , Biomass , Conservation of Natural Resources/economics , Conservation of Natural Resources/trends , Crop Production/economics , Digestion , Fermentation , Fishes/metabolism , Food Supply/economics , Forestry/economics , Fungal Proteins/biosynthesis , Fungal Proteins/chemistry , Fungal Proteins/economics , Humans , Industrial Waste/analysis , Industrial Waste/economics , Lignin/chemistry , Lignin/isolation & purification , Lignin/metabolism , Malnutrition/economics , Malnutrition/prevention & control , Nitrogen Cycle , Yeasts/chemistry , Yeasts/growth & development , Yeasts/metabolismABSTRACT
The mean trophic level of the farmed fish species in the Mediterranean has been increasing. We examined the farming-up hypothesis (i.e., the increase in the production of high-trophic-level species) in the Mediterranean by determining the trophic level of the aquafeeds (i.e., what the fish are fed) of 5 species of farmed marine fishes: common dentex (Dentex dentex), common pandora (Pagellus erythrinus), European seabass (Dicentrarchus labrax), gilthead seabream (Sparus aurata), and red porgy (Pagrus sp.). The mean trophic level of aquafeed used in mariculture from 1950 to 2011 was higher (3.93) than the prey farmed fish consume in the wild (3.72) and increased at a faster rate (0.48/decade) compared with that based on their diets in the wild (0.43/decade). Future expected replacement of the fishmeal and oil in aquafeeds by plant materials may reverse the farming-up trend, although there are a number of concerns regarding operational, nutritional, environmental, and economic issues. The farming-up reversal can be achieved in an ecologically friendly manner by facilitating the mariculture of low-trophic-level fishes and by promoting high efficiency in the use of living marine resources in aquafeeds.
Subject(s)
Aquaculture/methods , Conservation of Natural Resources , Fishes/physiology , Food Chain , Animal Feed , Animals , Aquaculture/trends , Diet , Mediterranean SeaABSTRACT
Ecosystem-based approaches to aquaculture integrate environmental concerns into planning. Social-ecological systems research can improve this approach by explicitly relating ecological and social dynamics of change at multiple scales. Doing so requires not only addressing direct effects of aquaculture but also considering indirect factors such as changes in livelihood strategies, governance dynamics, and power relations. We selected the community of Puerto Morazán, Nicaragua as a case study to demonstrate how the introduction of small-scale aquaculture radically transformed another key livelihood activity, lagoon shrimp fishing, and the effects that these changes have had on lagoons and the people that depend on them. We find that shrimp aquaculture played a key role in the collapse, in the 1990s, of an existing lagoon common-property management. Shrimp aquaculture-related capital enabled the adoption of a new fishing technique that not only degraded lagoons but also led to their gradual privatization. The existence of social ties between small-scale shrimp farmers and other community members mitigated the impacts of privatization, illustrating the importance of social capital. Since 2008, community members are seeking to communally manage the lagoons once again, in response to degraded environmental conditions and a consolidation of the shrimp industry at the expense of smaller actors. This research shows that shrimp aquaculture intersects with a complex set of drivers, affecting not only how ecosystems are managed but also how they are perceived and valued. Understanding these social-ecological dynamics is essential to implement realistic policies and management of mangrove ecosystems and address the needs of resource-dependent people.
Subject(s)
Aquaculture/economics , Ecosystem , Penaeidae/growth & development , Animals , Aquaculture/trends , Ecology , Environment , Government Regulation , Humans , Nicaragua , Politics , Socioeconomic FactorsABSTRACT
BACKGROUND: Undesirable impacts of climate change have been a common occurrence that has made fish farmers in developing countries adopt some climate-change adaptation strategies. However, little is known about determinants of climate-change adaptation strategies used by these fish farmers. This study, therefore, articulates novelties on adaptation to climate change, as well ascertains determinants of adaptation strategies used by fish farmers in Epe, Lagos State, Nigeria. RESULTS: Climate change adaptation strategies mostly used by fish farmers include frequent seeking for early warning information about climate change (76.7%) and avoidance of areas susceptible to flooding (60.0%). Climate-change adaptation strategies used by fish farmers were significantly influenced by access to early warning information (ß = 7.21), knowledge of farmers about climate change adaptation strategies (ß = 8.86), access to capital (ß = 28.25), and participation in workshop and conferences (ß = 37.19) but were reduced by number of fish stocking (ß = -2.06). CONCLUSION: The adaptation strategies used by fish farmers were autonomous and mostly determined by the access to credit facilities and information. Development policy should focus on carbon capture and storage technology in order to reduce adverse impacts of climate change, as well as making early warning information on climate change available to fish farmers. These will enhance adaptation to climate change.
Subject(s)
Adaptation, Physiological , Aquaculture , Climate Change , Disaster Planning/methods , Fishes/growth & development , Adaptation, Psychological , Adult , Animals , Aquaculture/economics , Aquaculture/methods , Aquaculture/trends , Catfishes/growth & development , Climate Change/economics , Developing Countries , Disaster Planning/economics , Educational Status , Female , Floods/economics , Government Programs , Humans , Information Seeking Behavior , Male , Middle Aged , Nigeria , Socioeconomic Factors , Surveys and Questionnaires , Tilapia/growth & development , WorkforceABSTRACT
This study is the investigation of Mediterranean aquaculture complete history, from 1950 to 2020. Both functional than geographical expansion of aquaculture is investigated, considering two main complementary aspects of aquaculture: farmed species and farming countries. According to the models proposed in this research, Nile tilapia and Egypt will dominate the future of Mediterranean aquaculture. Malta and Israel are the first producer countries, in relative terms. The most pervasive species are European sea bass and gilthead sea bream that are promising for a future expansion. In several countries, aquaculture has huge potentiality of development and it could grow with a factor of 5 or more, based on the ratio capture vs fishery on country size. Aquaculture total production in 2020 was of 2.8 Mln tons and it is expected to reach from 3.65 Mln tons in 2030. Aquaculture will grow in the countries and species that in this moment are dominant and the future of Mediterranean aquaculture will be characterized by the affirmation of these ones.
Subject(s)
Aquaculture , Aquaculture/methods , Aquaculture/trends , Animals , Mediterranean Region , FisheriesABSTRACT
The worldwide growth of aquaculture has been accompanied by a rapid increase in therapeutic and prophylactic usage of antimicrobials including those important in human therapeutics. Approximately 80% of antimicrobials used in aquaculture enter the environment with their activity intact where they select for bacteria whose resistance arises from mutations or more importantly, from mobile genetic elements containing multiple resistance determinants transmissible to other bacteria. Such selection alters biodiversity in aquatic environments and the normal flora of fish and shellfish. The commonality of the mobilome (the total of all mobile genetic elements in a genome) between aquatic and terrestrial bacteria together with the presence of residual antimicrobials, biofilms, and high concentrations of bacteriophages where the aquatic environment may also be contaminated with pathogens of human and animal origin can stimulate exchange of genetic information between aquatic and terrestrial bacteria. Several recently found genetic elements and resistance determinants for quinolones, tetracyclines, and ß-lactamases are shared between aquatic bacteria, fish pathogens, and human pathogens, and appear to have originated in aquatic bacteria. Excessive use of antimicrobials in aquaculture can thus potentially negatively impact animal and human health as well as the aquatic environment and should be better assessed and regulated.
Subject(s)
Anti-Infective Agents/pharmacology , Aquaculture/standards , Aquaculture/trends , Bacteria/drug effects , Drug Resistance, Bacterial , Health , Water Microbiology , Animals , Bacteria/genetics , Bacteria/metabolism , HumansABSTRACT
Aquaculture is currently the fastest growing food industry globally, and proposed expansion plans include substantial increases in production over the next decades. While this will improve global food security, contribute to the blue economy and create jobs locally, the potential negative impacts on the marine environment could be massive. The existing literature suggests that further research needs to be conducted into the dynamic nature of the social-ecological systems which host aquaculture. This paper presents the results of a choice experiment survey of Norwegian households' trade-offs between salmon production and job creation, and the detrimental impacts on the marine environment. Most respondents were at the outset neutral or supportive of plans for a substantial increase in aquaculture production. However, when informed about potential environmental impacts in terms of marine plastics and salmon lice affecting wild salmon stocks, and asked to trade these off against the positive effects, the majority opposed the plans and expressed a positive willingness-to-pay to avoid the planned expansion. Applying a hybrid mixed multinomial logit model we find that income, education and to some extent age, along with environmental attitudes, explain most of the variation in people's preferences. Support for large aquaculture expansion is higher among people who consume farmed salmon frequently and those living in areas with a high density of aquaculture farms. Hence, we do not find the so-called "not in my backyard" (NIMBY) effect. These results, which arguably contrast with previous studies of environmental impacts from aquaculture, can be useful for public planners globally as they consider expanding the blue economy.
Subject(s)
Aquaculture , Salmon , Animals , Humans , Aquaculture/statistics & numerical data , Aquaculture/trends , Copepoda , Ecosystem , Norway , Surveys and Questionnaires , Public Opinion , Environment , Conservation of Natural ResourcesABSTRACT
The 1996 World Food Summit defined food security as "Food security exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life". This paper looks at the status of production from both shrimp capture fisheries and shrimp aquaculture, as well as trade, in order to understand the contribution of the crustacean sector to overall fish production and thus to global food security. This paper also examines some sustainability issues that will potentially affect the contribution of the crustacean sector (particularly shrimp) to food security. These include sustainable shrimp capture fisheries, sustainable shrimp trade and sustainable shrimp aquaculture. The paper concludes that crustaceans are an important source of aquatic food protein. Production (as food and ornamental) and trade are extremely important for developing countries. It provides both economic development and empowerment in terms of contribution to GDP, consumption, employment, catch value and exports. The crustacean sector generates high value export products which enables producers to buy lower value products in the world market - thus a positive contribution to food security in both producing and exporting countries.
Subject(s)
Aquaculture , Crustacea , Fisheries , Food Supply , Shellfish , Animals , Aquaculture/trends , HumansABSTRACT
Shrimp farming in the Americas began to develop in the late 1970s into a significant industry. In its first decade of development, the technology used was simple and postlarvae (PLs) produced from wild adults and wild caught PLs were used for stocking farms. Prior to 1990, there were no World Animal Health Organization (OIE) listed diseases, but that changed rapidly commensurate with the phenomenal growth of the global shrimp farming industry. There was relatively little international trade of live or frozen commodity shrimp between Asia and the Americas in those early years, and with a few exceptions, most of the diseases known before 1980 were due to disease agents that were opportunistic or part of the shrimps' local environment. Tetrahedral baculovirosis, caused by Baculovirus penaei (BP), and necrotizing hepatopancreatitis (NHP) and its bacterial agent Hepatobacterium penaei, were among the "American" diseases that eventually became OIE listed and have not become established outside of the Americas. As the industry grew after 1980, a number of new diseases that soon became OIE listed, emerged in the Americas or were introduced from Asia. Spherical baculovirus, caused by MBV, although discovered in the Americas in imported live Penaeus monodon, was subsequently found to be common in wild and farmed Asian, Australian and African penaeids. Infectious hypodermal and hematopoietic necrosis virus (IHHNV) was introduced from the Philippines in the mid 1970s with live P. monodon and was eventually found throughout the Americas and subsequently in much of the shrimp farming industry in the eastern hemisphere. Taura syndrome emerged in Penaeus vannamei farms in 1991-1992 in Ecuador and was transferred to SE Asia with live shrimp by 1999 where it also caused severe losses. White Spot Disease (WSD) caused by White spot syndrome virus (WSSV) emerged in East Asia in â¼1992, and spread throughout most of the Asian shrimp farming industry by 1994. By 1995, WSSV reached the eastern USA via frozen commodity products and it reached the main shrimp farming countries of the Americas located on the Pacific side of the continents by the same mechanism in 1999. As is the case in Asia, WSD is the dominant disease problem of farmed shrimp in the Americas. The most recent disease to emerge in the Americas was infectious myonecrosis caused by IMN virus. As had happened before, within 3years of its discovery, the disease had been transferred to SE Asia with live P. vannamei, and because of its impact on the industry and potential for further spread in was listed by the OIE in 2005. Despite the huge negative impact of disease on the shrimp farming industry in the Americas, the industry has continued to grow and mature into a more sustainable industry. In marked contrast to 15-20years ago when PLs produced from wild adults and wild PLs were used to stock farms in the Americas, the industry now relies on domesticated lines of broodstock that have undergone selection for desirable characteristics including disease resistance.
Subject(s)
Aquaculture/trends , Crustacea/microbiology , Americas , Animals , Aquaculture/standardsABSTRACT
It is estimated that approximately 60% of disease losses in shrimp aquaculture have been caused by viral pathogens and 20% by bacterial pathogens. By comparison, losses to fungi and parasites have been relatively small. For bacterial pathogens, Vibrio species are the most important while for viral pathogens importance has changed since 2003 when domesticated and genetically selected stocks of the American whiteleg shrimp Penaeus (Litopenaeus) vannamei (Boone 1931) replaced the formerly dominant giant tiger or black tiger shrimp Penaeus (Penaeus) monodon (Fabricius 1798) as the dominant cultivated species. For both species, white spot syndrome virus (WSSV) and yellow head virus (YHV) are the most lethal. Next most important for P. vannamei is infectious myonecrosis virus (IMNV), originally reported from Brazil, but since 2006 from Indonesia where it was probably introduced by careless importation of shrimp aquaculture stocks. So far, IMNV has not been reported from other countries in Asia. Former impacts of Taura syndrome virus (TSV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV) on this species have dramatically declined due to the introduction of tolerant stocks and to implementation of good biosecurity practices. Another problem recently reported for P. vannamei in Asia is abdominal segment deformity disease (ASDD), possibly caused by a previously unknown retrovirus-like agent. Next most important after WSSV and YHV for P. monodon is monodon slow growth syndrome (MSGS) for which component causes appear to be Laem Singh virus (LSNV) and a cryptic integrase containing element (ICE). Hepatopancreatic parvovirus (HPV) and monodon baculovirus (MBV) may be problematic when captured P. monodon are used to produce larvae, but only in the absence of proper preventative measures. Since 2009 increasing losses with P. vannamei in China, Vietnam and now Thailand are associated with acute hepatopancreatic necrosis syndrome (AHPNS) of presently unknown cause. Despite these problems, total production of cultivated penaeid shrimp from Asia will probably continue to rise as transient disease problems are solved and use of post larvae originating from domesticated SPF shrimp stocks in more biosecure settings expands.
Subject(s)
Aquaculture/trends , Crustacea/microbiology , Animals , Aquaculture/standards , AsiaABSTRACT
Seafood is a highly traded food commodity. Farmed and captured crustaceans contribute a significant proportion with annual production exceeding 10 M metric tonnes with first sale value of $40bn. The sector is dominated by farmed tropical marine shrimp, the fastest growing sector of the global aquaculture industry. It is significant in supporting rural livelihoods and alleviating poverty in producing nations within Asia and Latin America while forming an increasing contribution to aquatic food supply in more developed countries. Nations with marine borders often also support important marine fisheries for crustaceans that are regionally traded as live animals and commodity products. A general separation of net producing and net consuming nations for crustacean seafood has created a truly globalised food industry. Projections for increasing global demand for seafood in the face of level or declining fisheries requires continued expansion and intensification of aquaculture while ensuring best utilisation of captured stocks. Furthermore, continued pressure from consuming nations to ensure safe products for human consumption are being augmented by additional legislative requirements for animals (and their products) to be of low disease status. As a consequence, increasing emphasis is being placed on enforcement of regulations and better governance of the sector; currently this is a challenge in light of a fragmented industry and less stringent regulations associated with animal disease within producer nations. Current estimates predict that up to 40% of tropical shrimp production (>$3bn) is lost annually, mainly due to viral pathogens for which standard preventative measures (e.g. such as vaccination) are not feasible. In light of this problem, new approaches are urgently required to enhance yield by improving broodstock and larval sourcing, promoting best management practices by farmer outreach and supporting cutting-edge research that aims to harness the natural abilities of invertebrates to mitigate assault from pathogens (e.g. the use of RNA interference therapeutics). In terms of fisheries losses associated with disease, key issues are centred on mortality and quality degradation in the post-capture phase, largely due to poor grading and handling by fishers and the industry chain. Occurrence of disease in wild crustaceans is also widely reported, with some indications that climatic changes may be increasing susceptibility to important pathogens (e.g. the parasite Hematodinium). However, despite improvements in field and laboratory diagnostics, defining population-level effects of disease in these fisheries remains elusive. Coordination of disease specialists with fisheries scientists will be required to understand current and future impacts of existing and emergent diseases on wild stocks. Overall, the increasing demand for crustacean seafood in light of these issues signals a clear warning for the future sustainability of this global industry. The linking together of global experts in the culture, capture and trading of crustaceans with pathologists, epidemiologists, ecologists, therapeutics specialists and policy makers in the field of food security will allow these issues to be better identified and addressed.
Subject(s)
Aquaculture/trends , Crustacea , Food Supply , Shellfish , Animals , Conservation of Natural Resources , Crustacea/microbiology , Fisheries , Humans , Shellfish/microbiologyABSTRACT
Animal health is fundamental to efficient animal production and, therefore, to food security and human health. This holds true for both terrestrial and aquatic animals. Although partnership between producers and governmental services is vital for effective animal health programmes, many key activities are directly carried out by governmental services. Noting the need to improve the governance of such services in many developing countries, the World Organisation for Animal Health (OIE), using the OIE Tool for the Evaluation of Performance of Veterinary Services, conducts assessments of Veterinary Services and Aquatic Animal Health Services (AAHS) to help strengthen governance and support more effective delivery of animal health programmes. While good governance and the tools to improve governance in the aquatic animal sector are largely based on the same principles as those that apply in the terrestrial animal sector, there are some specific challenges in the aquatic sector that have a bearing on the governance of services in this area. For example, the aquaculture industry has experienced rapid growth and the use of novel species is increasing; there are important gaps in scientific knowledge on diseases of aquatic animals; there is a need for more information on sustainable production; the level of participation of the veterinary profession in aquatic animal health is low; and there is a lack of standardisation in the training of aquatic animal health professionals. Aquaculture development can be a means of alleviating poverty and hunger in developing countries. However, animal diseases, adverse environmental impacts and food safety risks threaten to limit this development. Strengthening AAHS governance and, in consequence, aquatic animal health programmes, is the best way to ensure a dynamic and sustainable aquaculture sector in future. This paper discusses the specific challenges to AAHS governance and some OIE initiatives to help Member Countries to address them.