Animal welfare concerns raised in new Govt. report
The Home Office’s Animals in Science Regulation Unit (ASRU) annual report for 2024 paints a troubling picture of animal research in the UK. The report reveals that the number of licences granted for animal experiments has risen compared to 2023. It also details serious breaches of compliance - cases where animals suffered unnecessarily, died, or were killed due to failures in oversight.
Licences on the rise
Under UK law, scientists must hold the relevant licences, approved by ASRU, before they can use animals in the laboratory. In 2024, ASRU issued 2.6% more project licences than in 2023, giving permission for an additional 472 research projects involving animal experiments.
This means that by the end of 2024, there were 2,315 project licences in force, a shocking 25.2% increase from 2023.
In addition, the Unit granted personal licences to 2,164 more scientists, giving them permission to conduct procedures on animals. In total, 13,311 scientists now hold a personal licence - an increase of 15.7% in just one year.
These alarming statistics signal a continued reliance on animal models, despite mounting evidence that they are poor substitutes for human biology.
Non-compliance cases
The report details 146 cases of non-compliance, involving 22,204 animals. These breaches ranged from procedural errors to severe welfare failures. Among the most shocking examples were:
739 mice were experimented on ‘without relevant personal licence authority’
25 animals - including mice, bats, rats, and non-human primates - were without food for up to 3 days
2 cats were kept in facilities that ‘had fallen below the standard specified in the Home Office Code of Practice’
A mouse was ‘found suspended from cage lid by tail, without access to food and water’
4 dogs were ‘kept overnight in a pen that was too small’
A hamster was ‘mistakenly put in waste bag’
Mouse mother was ‘removed from cage and killed, resulting in unweaned pups starving to death’
15 fish died because the incorrect water was added to their tanks
62 mice were killed 'without appropriate training or authority'
These incidents are not isolated - they highlight systemic weaknesses in safeguarding animal welfare. Every breach is more than a statistic; it’s a sentient life subjected to unnecessary harm. At a time when advanced, humane alternatives exist, these findings underscore the urgent need for change.
How were these breaches addressed?
Each instance of non-compliance was met with what the Home Office calls a “remedy,” determined by the severity of the breach. However, the overall approach remains strikingly lenient. Even the most serious violations attracted only mild corrective measures.
No one has ever been prosecuted under UK animal welfare laws for laboratory breaches, and in 2024, not a single licence was revoked. Instead, enforcement was limited to administrative actions: 2 cases were remedied with a compliance notice, 36 received a letter of reprimand, and 139 addressed through inspector advice.
This pattern of minimal consequences raises serious questions about accountability and whether current regulations truly protect animals from harm.
How were these breaches discovered?
One of the most striking aspects of the 2024 report is how cases of non-compliance are uncovered. The vast majority - 101 cases, or 69% of confirmed breaches - were self-reported by the establishments themselves. An additional 36 were identified from Standard Condition 18 reports, whereby project licence holders notify ASRU if they have breached their licence conditions.
Only four cases (3%) were found during audits, three (2%) by the Licensing Team, and just one case each by the Regulatory Advice Team and via the Return of Procedures process - both accounting for less than 1% each.
This reliance on self-reporting raises serious concerns about the robustness of the regulatory system. When oversight depends primarily on voluntary disclosure, how many breaches go undetected? And what does this say about accountability in a system meant to protect animal welfare?
The government must do more to ensure that the laws designed to protect animals in laboratories are properly enforced, and it must deliver on its own roadmap to phase out animal testing. Without stronger action, these failings will continue year after year.
At The Humane Research Trust, we are committed to driving change by funding innovative, humane alternatives to animal experiments. By continuing to invest in human-relevant methods, we hope to ensure that the future of science doesn’t come at the cost of suffering.
- Dr Alison Giles CEO, The Humane Research Trust
Learn more about our work as a charity to end animal experiments
The Home Office’s Animals in Science Regulation Unit report paints a troubling picture of animal research in the UK. It reveals the rise in licences for animal experiments, plus details breaches where animals have suffered unnecessarily.
