Switzerland: Number of experiments in degree of severity 3 increased this year

According to a federal press release issued today, 522,636 animals were used in experiments in Switzerland in 2024 – around 12% fewer than in the previous year and the lowest annual figure since data collection began in 1983. The decline was seen mainly in experiments with degree of severity slight to moderate constraint. However, there was an increase in severely stressful experiments (severe constraint, severity level 3): 27,380 animals were used in this category, nearly 1,000 more than the year before and the highest number in roughly 25 years. According to the press release, mice remain by far the most frequently used species in animal experiments in Switzerland, accounting for about 67% of all experiments involving animals. In the experiments with the highest degree of severity (severity 3), over 90% of the animals were also mice. The rise in severity level 3 experiments underscores the importance of measures that go beyond mere reduction. Replacement – the complete substitution of animal experiments with alternative methods (e.g., in-vitro models, computer simulations, organoids) – remains a central element of ethical responsibility. To strengthen the 3R principle, the Federal Council launched the National Research Programme “Advancing 3R – Animals, Research and Society” (NRP 79) in 2022, which aims to promote the implementation of the 3R principles and thus to support the responsible use of laboratory animals.