Antimicrobial resistance, or AMR, is widely described by scientists and policymakers as one of the most pressing global challenges of the coming decades, and it is formally categorised as a ‘One Health’ problem because the forces driving it cut across human, animal and environmental health. Aquatic environments occupy a particularly awkward position in this picture. Water is an exceptional medium for the movement of bacteria and the genetic elements that carry resistance between them, and aquaculture systems both depend on and continuously interact with the rivers, canals and groundwater around them. When antimicrobial compounds enter pond water, whether through deliberate treatment or residual shedding, selective pressure favours bacteria that survive, and resistance genes can circulate through sediment, water columns and microbial communities in ways that are difficult to monitor and even harder to reverse. Professor Crumlish’s team argues that understanding these dynamics in a real production environment is essential to designing interventions that actually work.

Vietnam’s pangasius sector offers what the researchers describe as an ideal natural laboratory. Pangasius catfish farming is one of the world’s most important freshwater aquaculture industries by volume and export value, and its intensification over recent decades has been accompanied by growing recognition of AMR issues in the freshwater environments that host production. Intensive systems concentrate fish at high densities, which raises disease pressure, and when bacterial outbreaks strike, farmers frequently turn to antimicrobials as a first line of defence. The Stirling-led project will examine the causes and complexity behind resistance in these systems, but it will go a step further by also investigating the social and economic barriers that prevent alternative disease-management approaches from being adopted in the first place. That dual focus, on both the biology and the behaviour surrounding antibiotic use, is what the team describes as the study’s defining transdisciplinary character.

Professor Crumlish has been candid about the practical realities that drive antibiotic reliance on farms. When antibiotics stop working effectively in aquaculture, particularly in freshwater systems in Southeast Asia, farmers often have few alternatives available to them, yet they continue to trust antibiotic products even when those products are no longer effective. The result, she explains, is rapid development of resistance that can spill over into human, environmental and animal health, a pattern she identifies as a major concern. Rather than simply documenting the problem, the project has been designed to produce a novel research roadmap and a practical framework that can be adapted and applied in other countries facing similar challenges, an ambition that reflects the global nature of aquaculture and the shared biology of the resistance mechanisms involved.

The methodology at the heart of the project is co-creation. Over the next four years, researchers will work directly with farmers, policymakers, industry leaders and other stakeholders to ensure that any interventions they develop are both scientifically robust and realistically implementable. Alongside colleagues Dr Darren Green and Dr Noel Juvigny-Khenafou from Stirling’s Institute of Aquaculture, Professor Crumlish will collaborate with Dr Andrew Hoyle from the School of Computing, Data and Mathematical Sciences, Dr Saihong Li from the School of Communication, and Dr Till Stowasser from Stirling Business School. The inclusion of social scientists, data scientists and business researchers from the outset, rather than as an afterthought, is intended to surface the economic incentives, communication gaps and decision-making habits that determine whether a technically sound alternative to antibiotics ever reaches the pond.

The new grant builds directly on a body of previous research at Stirling investigating novel fish vaccines, including a recent trial conducted at the university’s National Aquaculture Technology and Innovation Hub, known as NATIH. Vaccination is widely regarded as one of the most promising tools for reducing antimicrobial dependence in finfish aquaculture, because preventing bacterial disease in the first place removes the need for therapeutic treatment. The transdisciplinary project will draw on data generated by these vaccine studies and share the findings with stakeholders as raw material for co-developing viable solutions and promoting better antibiotic stewardship across freshwater aquaculture. In effect, the team hopes to convert laboratory and trial-scale advances into a system-level change in how disease is managed on working farms.

The work will be carried out in partnership with the University of Glasgow, the University of Sydney, Can Tho University and Vietnam National University, a consortium that pairs UK and Australian research strength in microbiology, epidemiology and aquatic disease with Vietnamese institutions embedded in the regions where pangasius is actually farmed. This geographic and institutional spread matters for a problem of this kind. Resistance genes do not respect farm boundaries or national borders, and the conditions that shape antibiotic use, from extension services to market pressures, are locally specific. By grounding the research in Vietnamese production systems while connecting it to international expertise, the consortium aims to produce findings that are both locally actionable and globally transferable.

The funding envelope surrounding the project signals how seriously UK funders now treat the intersection of infection biology and food production. The £54 million programme, coordinated through UK Research and Innovation, is designed to prepare for future epidemics, tackle antimicrobial resistance and accelerate the development of next-generation animal vaccines. Professor Anne Ferguson-Smith, UKRI’s Executive Champion for Tackling Infections and Executive Chair of the Biotechnology and Biological Sciences Research Council, said the investment reflects UKRI’s central role in delivering government priorities and its long-standing commitment to convening partners across government to fund vital One Health research into human, animal and plant health. By pooling expertise from across the UK and global research and innovation ecosystem, she argued, related infectious disease challenges can be tackled in a more coordinated way, getting ahead of emerging biological threats and helping to protect people, animals, plants and the environment both domestically and internationally, advancing knowledge, improving lives and driving growth.

Professor Lucy Chappell, Chief Scientific Adviser at the Department of Health and Social Care and Chief Executive Officer of the National Institute for Health and Care Research, framed the investment in similarly interconnected terms. In a world where human, animal and environmental health are inherently linked and interdependent, she noted, diseases do not respect borders, and countries must work together to address their greatest health threats. Taking a One Health approach and bringing together experts from the UK and around the world, she said, allows threats to be identified earlier, strengthens resilience and delivers better health outcomes for the public. For the pangasius project specifically, that framing translates into a concrete ambition: within 48 months, to understand how resistance emerges in one of the world’s largest freshwater aquaculture industries, to map its impacts on production, and to chart a credible, farmer-endorsed path toward more sustainable disease management.

The stakes extend well beyond Vietnam. Aquaculture is among the fastest-growing food production sectors on the planet, and freshwater systems in Asia supply a substantial share of global fish consumption. If resistance renders existing antibiotics ineffective in these systems while alternatives remain out of economic or practical reach, the consequences will ripple through food security, rural livelihoods and public health simultaneously. What the Stirling-led consortium is proposing is essentially a test case for whether the aquaculture industry can decouple intensification from antimicrobial dependence, not through top-down regulation alone but through solutions built with the people who will have to use them. If the roadmap that emerges proves adaptable to other countries and other species, as the team intends, the humble catfish ponds of the Mekong Delta may end up shaping how the world manages infection far beyond their own waters.

Subject of Research: Antimicrobial resistance in Vietnamese pangasius catfish aquaculture

Article Title: University of Stirling secures £2.4M grant for major aquaculture project

Article References: University of Stirling secures £2.4M grant for major aquaculture project. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: antimicrobial resistance, aquaculture, pangasius catfish, Vietnam, One Health, University of Stirling, UKRI, fish vaccines, antibiotic stewardship, freshwater farming, Institute of Aquaculture, transdisciplinary research

Salmon lice are ectoparasites that feed on the skin, mucus, and blood of fish. Their feeding activity creates open wounds that can become infected, reducing the market value of farmed fish and increasing the likelihood of secondary infections. Beyond the direct damage to individual animals, infestations impose enormous costs on the aquaculture sector. Sea lice infestations in Atlantic salmon farming cost the industry more than one billion dollars a year through mortality, lost production, and the implementation of control measures. Understanding the biology of the parasite at a molecular level is therefore considered a critical step in developing new, safe, and effective strategies for its control.

The central innovation of the new study lies in its sampling approach. Previous methods for extracting SEPs from salmon lice involved pooling together large numbers of individuals before analysis. While such pooled samples could yield enough material for detection, they averaged out the natural differences between individual lice. Those differences, the researchers argue, can provide vital insight for developing targeted treatments or vaccines, because they reveal how variable the parasite’s secretory arsenal is across a population. By contrast, the new method allows the collection of high-quality samples from a single louse per test, with substantial yields of secretory proteins per individual, while also reducing the potential for contamination of the samples with louse faecal material.

The collection procedure itself is elegantly simple in concept. Researchers place a small drop of solution over the mouthparts of an individual louse and allow the animal to release its secretory proteins into that droplet. The protein-laden solution is then examined using liquid chromatography tandem mass spectrometry, a state-of-the-art analytical technique that separates the components of a sample, breaks them into fragments, and analyses those fragments to reveal the exact protein composition of each sample. Applied to single-louse samples, this approach produces a detailed proteomic fingerprint of what each individual parasite is secreting at the moment of collection.

Using this assay, the team identified 148 secretory proteins in total, 64 of which were detected across each of the tested conditions. The consistency of that core set of proteins across individuals and conditions makes it particularly interesting from an applied perspective, because proteins that are reliably present in the parasite’s secretions could represent potential targets for vaccine development. A vaccine that prompts fish to mount an immune response against molecules the louse depends on for feeding or immune evasion could, in principle, reduce the parasite’s ability to establish itself on its host.

One of the most striking findings of the study was the degree of variation observed between individual lice. The secretory protein profiles of single animals showed wide variation in both the number and the diversity of proteins detected, a pattern the researchers note is consistent with what has been seen in other ectoparasites such as ticks and mosquitoes. This individual-level variability would have been invisible in pooled samples, and it underscores why the ability to study lice one at a time matters. If different lice deploy different combinations of secreted molecules, control strategies may need to account for that diversity in order to be effective across a whole parasite population.

The researchers emphasise that the methodology has value well beyond cataloguing proteins. Because the protocol allows reproducible, reliable, and efficient extraction of high concentrations of salmon louse secretions while minimising faecal contamination, it can serve as a platform for future experiments. Mr Dindial noted that the protocol could be used to investigate how drug or therapeutic treatments might alter louse secretory activity, which would allow scientists to test whether candidate interventions disrupt the parasite’s ability to feed or evade immunity. In this way, the assay functions both as a discovery tool and as a screening tool for evaluating new control measures.

The study also builds directly on a first-of-its-kind investigation led by Mr Dindial and published the previous year, which uncovered major differences in the secretions the parasite uses to feed and evade the immune system at different stages of its life cycle. Taken together, the two studies sketch a picture of a parasite whose chemical toolkit changes as it develops, and whose secretions vary from one individual to the next. That level of biological detail is exactly the kind of information needed to design interventions that are precise enough to work against the parasite while avoiding some of the drawbacks of existing treatments.

The need for better tools is pressing. Various treatments have been developed to tackle sea lice infestations in Atlantic salmon aquaculture, but some of these can be expensive, unreliable, environmentally damaging, or harmful to animal welfare. Chemical treatments can lose effectiveness as the parasite develops resistance, and mechanical or biological control approaches each carry their own limitations and costs. A strategy grounded in the parasite’s own secretory biology, whether through vaccination, targeted therapeutics, or the breeding of more resistant fish, offers the prospect of control measures that are both more effective and more sustainable than those currently available.

The research was funded by EastBio as part of Mr Dindial’s PhD studentship, with a funding contribution from the Moredun Research Institute. It was conducted in collaboration with the project Towards lice-resistant salmon: functional genetics and genome editing to enhance disease resistance in aquaculture, funded by the UK Biotechnology and Biological Sciences Research Council, the Sustainable Aquaculture Innovation Centre, and Benchmark Genetics Limited, and involving partners from the Roslin Institute at the University of Edinburgh, the Centre for Environment Fisheries and Aquaculture Science, the Atlantic Veterinary College at the University of Prince Edward Island, and Kames Fish Farming Ltd. The study, titled Investigation of a novel assay for the proteomic screening of the secretory and excretory products of individual salmon lice Lepeophtheirus salmonis, was published in Veterinary Parasitology on 1 May 2026. As the aquaculture industry continues to search for durable solutions to its costliest parasite problem, the ability to read the chemical language of individual lice may prove to be a decisive step forward.

Subject of Research: Proteomic analysis of secretory and excretory products of individual salmon lice for parasite control in aquaculture

Article Title: A University of Stirling study could pave the way for the more efficient study of the secretions that salmon lice use to avoid fish defences, potentially enabling the development of new strategies to protect salmon from infestations. Research led by PhD

Article References: A University of Stirling study could pave the way for the more efficient study of the secretions that salmon lice use to avoid fish defences, potentially enabling the development of new strategies to protect salmon from infestations. Research led by PhD. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: salmon lice, aquaculture, proteomics, mass spectrometry, secretory proteins, Lepeophtheirus salmonis, vaccine development, parasite control, Atlantic salmon, University of Stirling, Veterinary Parasitology, immune evasion