What are animal experiments?
The first anti-vivisection campaigners grew to prominence in the 1800s, and 1876 saw the passage of the first UK law aimed at regulating animal testing.
From ancient Greece, through Victorian Britain to the era of genetic research, millions and millions of animals have been used in experiments.
These laboratory animals have neither choice nor voice; they’re used to test the toxicity and safety of chemicals used in household products, for agriculture, industry and medicinal research. Some countries still require animal testing of cosmetics, too.
While the use of defenceless, sentient animals in testing may have advanced medicine, the debate over the ethics of the practice has raged alongside.
The first anti-vivisection campaigners grew to prominence in the 1800s and 1876 saw the first UK law aimed at regulating animal testing.
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Severity of UK animal tests
How do you quantify suffering? The culture of secrecy around animal testing means we’re not allowed to get a full picture of how the animals are treated or know exactly what happens to them.
But we do have access to the official scale of severity that’s imposed on innocent animals, which makes for grim reading:
- Sub-threshold: a procedure that was authorised under a project licence but did not actually cause suffering above the threshold of regulation, that is, it was less than the level of pain, suffering, distress or lasting harm caused by inserting a hypodermic needle according to good veterinary practice.
- Non-recovery (under general anaesthesia): a procedure that was carried out under general anaesthesia without recovery.
- Mild: any pain or suffering experienced by an animal that was, at worst, only slight or transitory and minor so that the animal returns to its normal state within a short period of time.
- Moderate: a procedure that caused a significant and easily detectable disturbance to an animal’s normal state, but this was not life-threatening. Most surgical procedures carried out under general anaesthesia and with good post-operative pain relief would be classed as moderate.
- Severe: a procedure that caused a major departure from the animal’s usual state of health and wellbeing. This would usually include long-term disease processes where assistance with normal activities such as feeding and drinking were required, or where significant deficits in behaviours/activities persist. It includes animals found dead unless an informed decision can be made that the animal did not suffer severely prior to death.
Where we are today
The UK Government released its strategy to phase out animal testing, in November 2025. It has 6 key objectives:
- Accelerate the replacement of animals in science to phase out their use.
- Achieve equal or better research and testing outcomes using alternative methods.
- Drive private investment in alternative methods to boost innovation and growth.
- Improve regulatory confidence and acceptance of alternative methods.
- Create infrastructure and partnerships to unlock value from UK data.
- Position the UK as a global leader in alternative methods.
Whilst we cautiously welcome this strategy after years of campaigning for it, we will continue to push for acceleration in areas where there are significant gaps and lack meaningful focus.
Moving in the right direction?
Not yet…
In 2025, the Home Office published a report showing that across all species, 3% of experimental scientific procedures involved severe suffering in 2024. That’s almost 43,000 experiments. The report also shows a 2% decrease in the overall number of experiments carried out on animals since the previous year of 2023. It’s good to see the numbers going down, but it’s nowhere near enough of a reduction, and, at this pace, it’ll be hundreds of years before we finally reach zero. It has to be accelerated.
The UK could be a world leader in researching and implementing non-animal methods, but we’re still the biggest user of animals for experimental purposes in Europe, followed by Germany and France. The UK is not a world leader currently, and we’ll continue to push the Government to actually do what it claims to be doing, which is phasing out animal testing.
The future
Many research facilities are now ditching some animal tests, embracing non-animals technological advances and moving more quickly to human trials.
The global non-animal testing market was valued at $9.8 billion in 2021 with significant further growth predicted by 2030. Apart from saving animal lives and eliminating suffering, non-animal testing is often more cost-effective, efficient and quicker. Methods include organ-on-chip, in-silico computer simulations, cell and tissue culture (in-vitro), 3D printing, and artificial skin models.
At Naturewatch Foundation, we strongly support investment in human-based science. With millions of pounds of UK public money going into the life sciences sector, we urge the government to support and fund modern non-animal research methods and for industry to play its part, too.
How you can help
There are lots of ways to help with our work, from making a donation through to holding fundraising events or even getting involved as a volunteer. Below, you can explore the different ways to help us continue raising standards for animals.