New research from the Royal Veterinary College (RVC), carried out in collaboration with research institutions in South and Southeast Asia, provides one of the first directly comparable assessments of antimicrobial residues in poultry, using a standardised testing approach across multiple countries. The findings offer new insights for food safety and public health, after identifying antimicrobial residues in chicken meat samples from Bangladesh, India and northern Vietnam, with some exceeding internationally recognised safety limits.
Antimicrobial resistance (AMR) is a growing global health concern, possibly driven in part by the use of antimicrobials in food-producing animals. When these medicines are used to treat or prevent disease, traces can remain in the meat if sufficient time is not allowed for them to leave the animal’s system before slaughter. These residues may contribute to AMR, posing potential risks to both animal and human health.
In the UK and the EU, strict regulations mean antimicrobial residues exceeding safety limits are rare. However, much less is known about the prevalence in developing regions, where there is less regulation and limited awareness of withdrawal periods (the time between end of treatment and slaughter). Although international benchmarks provide a consistent standard for food safety, differences in testing methods have made cross-country comparisons difficult.
To address this, a study led by Ludovic Pelligand, Professor of Veterinary Clinical Pharmacology and Anaesthesia at the RVC, was conducted in collaboration with international partners and local institutions in Bangladesh, India and Vietnam. Researchers analysed 558 chicken breast samples collected in 2021-22, at the end of the production cycle and at points of sale in each country. Samples were tested for 69 veterinary antimicrobials using a method aligned with EU reference laboratory standards, carried out at Nanyang Technological University in Singapore.
The findings revealed a high prevalence of non-compliant samples. At some points of sale, between 3.7% and 8.6% of samples exceeded safety limits, compared to around 0.05% to 0.09% in the EU for 2021-22. This suggests antimicrobial use, including potential administration close to slaughter, as well as possible contamination from other sources such as chicken feed and drinking water.
This level of non-compliance highlights important implications for public health and global food systems, particularly in regions where regulatory oversight may be limited. There are also economic consequences, as failure to meet international residue standards can act as a barrier to trade.
By establishing a baseline for antimicrobial residue levels across multiple countries, this research provides a clearer picture of exposure within poultry systems. This evidence can support policymakers in strengthening antimicrobial stewardship, improving food safety and protecting consumer health, while also informing future research and targeted interventions to reduce antimicrobial use.
Building on this work, the research team will now investigate how antimicrobial use throughout the poultry production cycle contributes to residue levels in meat and the development of antimicrobial resistance, through a new UKRI-funded project involving partners in Vietnam and the UK.
Ludovic Pelligand, Professor of Veterinary Clinical Pharmacology and Anaesthesia at the RVC, said: “This is a landmark study as until now, no cross-country residue data was available with the same standardised methodology in Asia. It required a sustained international effort, for analytical method transfer, sample collection to coordinated parcel of frozen parcels. We hope the momentum provided by the study will help raise awareness about veterinary drug residues and improve food safety locally.”
This research was funded by the UK Research and Innovation Global Challenges Research Fund through the One Health Poultry Hub.