Antimicrobial resistance (AMR) demands collective action to reduce and mitigate its threats. The Quadripartite collaboration of the World Health Organization (WHO), Food and Agriculture Organization of the United Nations (FAO), United Nations Environment Programme (UNEP) and World Organization for Animal Health (WOAH) has led development and implementation of National Action Plans (NAPs) that describe approaches each country will take to tackle AMR. All antimicrobial users and sectors should be included, and the Quadripartite encourages a One Health approach. Aquaculture has received mixed coverage in NAPs: Here, we argue why aquaculture requires special consideration. Aquaculture is a diverse, global collection of industries and activities, with heterogeneity in systems and species greatly exceeding terrestrial food-animal production, with products traded internationally in huge volumes. Almost 6 % of global total antibiotic usage is estimated to be applied in aquaculture, with per-biomass quantities in some species exceeding usage in human and terrestrial food-animals. The watery nature of aquaculture interconnects it with other One Health compartments: humans, other animals and the wider environment. Rapid industry growth challenges relatively detached stakeholders such as regulators and NAP creators to remain abreast of changing practices, whilst support capabilities and capacity, e.g., health services, typically lag behind growing needs. To integrate aquaculture effectively into next-generation NAPs, ensuring policies cover the One Health spectrum, NAP creators need to recognise the diversity of aquaculture and initiate engagement across associated value chains, especially health service providers. Disentangling the industry can assist formulation of realistic policies for heterogenous contexts and identify pathways to implementation. Resource allocation must be appropriate and include relevant government departments, whilst improved ways to track and monitor AMR, including those international activities that impact AMR domestically, through suitable data collection are key to monitoring and evaluating policies. Better NAPs are crucial to addressing AMR and this coordinated global approach provides our best opportunity for success.

Animal-source foods provide essential nutrients for humans, however, the use of nutrient-dense (i.e., high in nutrients but low in calories) and digestible resources for animal feeds is controversial as it may reduce the net contribution of farmed animals to global food supply, and hence to food security. Redirecting resources edible by humans to direct consumption as food can increase resource use efficiency and food supply, however, what can be considered as edible by humans is context dependent. The objective of the present study is to assess the net contribution of ten contrasting tilapia production systems from eight different countries to the supply of nutrients of importance for human health. To do so we calculated the human-edible nutrient conversion ratio (HeNCR), which is the human-edible nutrients in the inputs (feed) divided by the human-edible nutrients in the outputs (animal products) of the systems. We showed that tilapia systems can be net producers of proteins, but that in general, much more human edible micronutrients (5 to 175 times) and EPA + DHA (about 7 times) were in the feed used than in the fish produced. Four scenarios combining different definitions for feed and fish edibility were tested to explore the effect of different dietary changes on the performances of the tilapia systems. Scenario analysis revealed that the direct use of edible ingredients as food generates more nutrients than the consumption of fish. Consumers’ preferences, and therefore our definition of what is edible, may have to evolve in order to maximize food resource use.

As climate impacts worsen, novel technologies to draw down atmospheric carbon are gaining attention. One such approach is ocean-based carbon dioxide removal (OCDR). However, the potential environmental side-effects of large-scale OCDR deployment remain understudied. Here, we present a systematic literature review of the life cycle assessments (LCAs) of OCDR approaches. We find that current OCDR LCAs have a limited scope, often overlook environmental impacts beyond global warming, and that LCA as a method is currently limited in capturing aquatic impacts. We provide several recommendations for future work, such as using a functional unit of storing atmospheric carbon over a specified time horizon and in a specified medium, performing cradle-to-grave analysis, including more (marine) environmental impacts, and estimating uncertainties. We also emphasise the need to develop the LCA methodology further for better assessing marine environment impacts.

The intensification of aquaculture industries around the globe has led to increased susceptibility and exposure to diseases. To ensure the well-being of animals and the profitability of the industry, many aquaculture farms resort to antibiotic treatments. However, with the increasing presence of antimicrobial resistance (AMR), it has become important to regulate and limit the use of antibiotics, especially in animal production and regarding the antibiotics that are deemed as critically important for human health by the World Health Organization (WHO). This review describes how AMR mitigation strategies have developed over time in international settings and how they relate to aquaculture. Furthermore, we analyzed how different countries and regions abide by these statutes, as well as the antibiotic standards from a selection of certification schemes. Our results show that the role of aquaculture has been inexplicitly addressed in international guidance documents and that there is a need to further increase the activities of aquaculture operations in combating AMR, with an emphasis on alternatives to antibiotic use. We also found that most countries and regions allow the highest priority-, or critically important antibiotics in aquaculture, which could have detrimental effects on animal, environmental, and public health. As a result, most countries fail to comply with the recommendations and standards set by international organizations and certification schemes.

Aquaculture is a crucial sector for Egyptian food production, providing a cheap source of animal protein while securing income and employment for a substantial part Egypt's population. Nile tilapia (Oreochromis niloticus) is the most commonly produced fish, usually farmed in earthen ponds around the Northern Delta Lakes. A common practice among farms is to fertilize ponds with chicken manure (CM) in order to increase nutrient levels and promote phytoplankton, consumed by the fish. However, with reports of use of antibiotics in Egypt's poultry sector, and that CM contains residues of antibiotics, antibiotic resistant pathogens and antibiotic resistance genes (ARGs) are production benefits large enough to compensate a potential health hazard?

Using production data from 501 aquaculture farms and fish pond sediment from 28 ponds we evaluated potential benefits in yields and profitability for farms using CM for fertilization, and used qPCRs to screen sediments for three antibiotic resistance genes coding for resistance to the most commonly used antibiotics in the poultry sector. The analysis showed no significant benefits to fish yields or profitability in farms where CM was applied, but a risk of significantly increased nutrient loads. Meanwhile, we detected increased abundances of tetA and tetW resistance genes in fish pond sediment where CM was applied. With the risk of disseminating ARGs and causing eutrophication of local waterways, we recommend that Egyptian tilapia pond farmers refrain from using CM and adopt best management practices for increasing farm profitability in order to to reduce environmental and health hazards.

A circular economy is considered one way to reduce environmental impacts of human activities, by more efficient use of resources and recovery, resulting in less waste and emissions compared to linear take-make-dispose systems. Muscat et al. developed five ecological principles to guide biomass use towards a circular economy. A few studies have demonstrated environmental benefits of applying these principles to land-based food systems, but to date, these principles have not been explored in aquaculture. The current study expands on these principles and provides a narrative review to (i) translate them to aquaculture, while identifying implications for the main species and production systems, and (ii) identify the main pathways to make aquaculture more circular. We show that the underlying concepts of the ‘safeguard’, ‘entropy’, and ‘recycle’ principles have been well researched and sometimes well implemented. In contrast, the ‘avoid’ and ‘prioritise’ principles have been explored much less; doing so would provide an opportunity to decrease environmental impacts of aquaculture at the food-system level. One example is prioritising the production of species that contribute to food and nutrition security, have low environmental impacts and thinking at wider food system scale to avoid feed-food competition in aquaculture. We identified six priorities that could make aquaculture more circular: (i) increase production and demand for the most essential species, (ii) decrease food loss and waste at farm and post-harvest stages, (iii) support nutrient recycling practices at multiple scales, (iv) adapt aquafeed formulations, (v) inform consumers about benefits of species of low trophic levels and other environmentally friendly aquatic foods, and (vi) address urgent research gaps.

IntroductionAntimicrobial resistance (AMR) is a challenge to modern medicine. Interventions have been applied worldwide to tackle AMR, but these actions are often not reported to peers or published, leading to important knowledge gaps about what actions are being taken. Understanding factors that influence the implementation of AMR interventions and what factors are relevant in low-middle-income countries (LMICs) and high-income countries (HICs) were the key objectives of this exploratory study, with the aim to identifying which priorities these contexts need.MethodsA questionnaire was used to explore context, characteristics, and success factors or obstacles to intervention success based on participant input. The context was analyzed using the AMR-Intervene framework, and success factors and obstacles to intervention success were identified using thematic analysis.ResultsOf the 77 interventions, 57 were implemented in HICs and 17 in LMICs. Interventions took place in the animal sector, followed by the human sector. Public organizations were mainly responsible for implementation and funding. Nine themes and 32 sub-themes emerged as important for intervention success. The themes most frequently reported were 'behavior', 'capacity and resources', 'planning', and 'information'. Five sub-themes were key in all contexts ('collaboration and coordination', 'implementation', 'assessment', 'governance', and 'awareness'), two were key in LMICs ('funding and finances' and 'surveillance, antimicrobial susceptibility testing and preventive screening'), and five were key in HICs ('mandatory', 'multiple profiles', 'personnel', 'management', and 'design').ConclusionLMIC sub-themes showed that funding and surveillance were still key issues for interventions, while important HIC sub-themes were more specific and detailed, including mandatory enforcement, multiple profiles, and personnel needed for good management and good design. While behavior is often underrated when implementing AMR interventions, capacity and resources are usually considered, and LMICs can benefit from sub-themes captured in HICs if tailored to their contexts. The factors identified can improve the design, planning, implementation, and evaluation of interventions.

Background: With AMU projected to increase, South East Asia (SEA) is at high risk of experiencing disproportionate health, social, and economic burdens due to antimicrobial resistance (AMR). Our objective was to identify factors influencing AMR in SEA’s food system and places for intervention by integrating the perspectives of experts from the region to inform policy and management decisions.

Materials and methods: We conducted two 6.5 h workshops and two 90-min interviews involving 18 AMR and other disciplinary experts from human, animal, and environment sectors who brainstormed the factors influencing AMR and identified leverage points (places) for intervention. Transcripts and workshop materials were coded for factors and their connections and transcribed into a causal loop diagram (CLD). Thematic analysis described AMR dynamics in SEA’s food system and leverage points for intervention. The CLD and themes were confirmed via participant feedback.

Results: Participants constructed a CLD of AMR in the SEA food system that contained 98 factors interlinked by 362 connections. CLD factors reflected eight sub-areas of the SEA food system (e.g., government). Seven themes [e.g., antimicrobial and pesticide use and AMR spread (n = 40 quotes)], six “overarching factors” that impact the entire AMR system [e.g., the drive to survive (n = 12 quotes)], and 10 places for intervention that target CLD factors (n = 5) and overarching factors (n = 2) emerged from workshop discussions.

Conclusion: The participant derived CLD of factors influencing AMR in the SEA food system demonstrates that AMR is a product of numerous interlinked actions taken across the One Health spectrum and that finding solutions is no simple task. Developing the model enabled the identification of potentially promising leverage points across human, animal, and environment sectors that, if comprehensively targeted using multi-pronged interventions, could evoke system wide changes that mitigate AMR. Even targeting some leverage points for intervention, such as increasing investments in research and capacity building, and setting and enforcing regulations to control antimicrobial supply, demand, and use could, in turn, shift mindsets that lead to changes in more difficult to alter leverage points, such as redefining the profit-driven intent that drives system behavior in ways that transform AMU and sustainably mitigate AMR.

Finding ways to keep global warming under 1.5 degrees Celsius is urgent and will need a portfolio of solutions. Seaweeds are marine photosynthetic organisms that humans harvest either from the wild or farm, to be used in many applications and providing various ecosystem services. Large scale farming of seaweeds for absorbing carbon has lately been promoted as a climate “fix”. The major shortcomings of this argument relate to the idea that a carbon sink function should exist through carbon accumulation in seaweed biomass simultaneously as seaweeds are consumed as food by humans, fed to animals, or used in many alternative applications. This carbon instead enters the fast carbon cycle and does not provide any “carbon sink” function. Radical suggestions of intentionally transfer of farmed seaweeds to the deep-sea to accomplish a longer removal are highly questionable from feasibility, economic, ecosystem effects and ethical resource use perspectives. Development of “ocean forests” for carbon capturing through farming should not be compared to forests on land as these provide carbon removal from the atmosphere at sufficiently long time scales to be qualified as carbon sequestration - thus making a difference related to reducing atmospheric greenhouse gas concentrations. Seaweeds can, however, play a role in reducing greenhouse gas emissions from the overall food system through carbon offset - i.e. if replacing food, feed, and/or materials that have larger carbon footprints. The fate/cycling of carbon as particulate and dissolved matter from both farmed and wild seaweeds, are however not fully understood, especially with respect to pathways and time scales relevant for carbon removal/storage. Another potential pathway for their role in decarbonization may be through reducing enteric methane emissions from ruminants and also through bioenergy production. More research is, however, needed for understanding the contributions from such interventions. Presenting seaweed farming as a quick fix for the climate risks facilitating misdirected investments (for carbon abatement solutions) and reducing demand for specific research and technological development that will be needed for increasing our understanding about seaweeds’ contribution to food/feed systems and additional sustainability services and benefits. 

Among the species caught by small-scale fisheries in Bangladesh, hilsa (Tenualosa ilisha) is the most important by volume and of great cultural importance. Hilsa fishing boats have over the last decade been mechanized, enabling longer trips and larger hauls. This development has, however, also resulted in increased fishing pressure and increased reliance on fossil fuels. This study estimates the fuel use intensity (FUI) of hilsa fishing, calculated as fuel per unit landed mass of hilsa at one of the main landing stations (Chairman ghat) in the coastal area of Noakhali district, Bangladesh. Primary data were collected from three types of artisanal fishing boats commonly used in hilsa fisheries, namely small boats (Choto/Khosa tempo), medium boats (Tempo), and large boats. Our results show a higher fuel use intensity in small boats (750 +/- 468 l t-1), compared to medium (495 +/- 270 l t-1) and large boats (576 +/- 365 l t-1). Considering the gross catch and total fuel consumption of all boats, the absolute FUI is estimated at 463 l t-1. Thus, the FUI of hilsa fishing is slightly lower than the average for global fisheries FUI (489 l t-1). In terms of greenhouse gas (GHG), not including other lifecycle inputs (e.g. infrastructure, ice, supply chain etc.) than fuel (i.e. diesel, LPG, and wood), the average global warming impact is 1.72 +/- 0.34 tonnes CO2-eq. t-1 overall catch. This study provides a baseline estimate for FUI and GHG emissions from contemporary hilsa fishing, and proposes solutions for addressing environmental issues and improving the overall performance of the sector.