Swiss animal testing falls to record low but severe experiments rise

Swiss laboratories used 507,863 animals in 2025, the lowest annual total recorded since national statistics began in 1983. The Federal Office for Food Safety and Veterinary Affairs published the figures on September 15, 2026, showing a decline of around 15,000 animals, or 3%, from the previous year.

The reduction places Switzerland at a new low in its long-running effort to limit the use of animals in research. Yet the same figures show a rise in the most severe category of experiments, giving the annual statistics a sharper edge for policymakers, scientists and animal welfare groups.

The government classifies experiments across four levels. Level 0 covers procedures that cause no distress. Level 1 involves mild distress, while level 2 covers moderate distress. Level 3, the highest category, includes procedures that may cause severe pain, prolonged suffering or serious impairment of an animal’s general condition.

In 2025, around 29,400 animals underwent level 3 procedures. That figure increased by 7.4% in one year and reached its highest point in 26 years. Switzerland therefore recorded fewer experiments overall while reporting more animals exposed to the most serious forms of distress.

Mice made up 66% of all animals used in Swiss experiments in 2025. Birds accounted for 13%, while rats and fish each represented 8%. The remaining 5% covered other species, according to the federal figures.

The number of mice declined during the year. Fish use, however, rose significantly, making them the clearest species level change highlighted in the government data. The published figures do not provide a detailed explanation for that increase.

Species totals provide one measure of scale, but they do not describe the experience of each animal. Swiss reporting also records the severity assigned to procedures, ranging from no distress to severe distress. That classification allows the annual count to show where reductions have occurred and where the burden has intensified.

The continued dominance of mice reflects their widespread use in biomedical research. Their biology, short reproductive cycle and established laboratory methods have made them a standard model in studies of disease. Fish and birds are also used in research, though the purposes and procedures vary across projects.

The figures give the public a broad national picture. They do not, in the source data, identify which institutions or cantons drove the annual increase in severe procedures or the rise in fish use.

Around 73% of laboratory animals were used for research into human diseases. Cancer research accounted for one of the largest areas, alongside work on neurological and mental illnesses, according to the Federal Office for Food Safety and Veterinary Affairs.

Those priorities connect the statistics to some of the most difficult problems in medicine. Cancer and disorders affecting the brain remain major fields of research, with scientists studying disease mechanisms, potential treatments and the safety of new therapies. The government data does not break down the 2025 total by individual disease, institution or canton.

Medical research also helps explain why the number of animals used and the severity of procedures can move in different directions. A smaller research programme may still involve complex interventions on fewer animals. Conversely, a larger number of animals can be used in procedures classified at lower severity. The annual totals alone cannot measure the scientific value or outcome of those projects.

Switzerland has invested in alternatives, including computer modelling, cell based methods and other technologies designed to reduce reliance on live animals. Empa has also worked on an artificial intelligence mouse model intended to support that effort. Such tools may reduce animal use over time, although the government’s 2025 figures show that animal experiments remain part of Swiss biomedical research.

Level 3 experiments reached approximately 29,400 animals in 2025, an increase of 7.4% from 2024. It was the highest number recorded in 26 years, despite the overall total falling to its lowest point.

Under Switzerland’s four-part system, level 3 covers severe distress. The category can include severe pain, prolonged suffering or a serious deterioration in an animal’s general condition. The classification does not mean every level 3 procedure has the same duration or medical purpose, but it identifies the highest band of regulated distress.

The source figures do not state which research fields caused the increase, nor do they identify the animals involved. They show a national result that will draw attention from the scientific community and animal welfare organisations as Switzerland considers how to measure progress.

A falling total can indicate that fewer animals enter laboratories. It does not show whether the procedures that remain have become less invasive. The rise in level 3 use makes severity an essential part of any assessment of the country’s research policy.

The government’s statistics therefore put two indicators side by side: the total number of animals and the number facing the highest level of distress. Both will matter in the debate over future regulation.

A popular initiative filed in 2024 calls for a comprehensive ban on animal testing in Switzerland. The proposal has not yet been put to a vote, and the government recommends rejecting it. The new statistics are likely to keep the issue prominent in national politics.

Supporters of a ban can point to the rise in the most severe category and argue that lower overall use does not resolve the welfare issue. They can also press for faster development and adoption of non-animal methods in laboratories, particularly in fields where artificial intelligence, cell systems or computer models may offer alternatives.

Opponents of a ban are likely to emphasise the role of animal research in studies of cancer, neurological disease and mental illness. Around 73% of laboratory animals were used for human disease research in 2025. The government’s position indicates that it considers a complete prohibition incompatible with current research needs.

The timing of a nationwide vote remains unknown. Until then, the annual figures will shape the discussion. Switzerland’s record low total offers evidence of a long-term reduction in animal use, while the level 3 increase gives campaigners and lawmakers a separate measure against which to judge progress.

Future scrutiny will focus on both directions of the trend: whether total use continues to fall and whether laboratories can reduce the number of animals subjected to severe distress.