Inside Britain’s Laboratories: 5 Experiments Animals Are Enduring Today
This week, the UK Government will publish annual statistics on the number of scientific procedures conducted on animals in Great Britain during 2025.
When those figures are released, headlines will focus on whether the total number has risen or fallen. But behind every single statistic is an individual animal who spent their life trapped in a laboratory, subjected to horrific procedures where they are injected with substances, infected, and sliced open, before being killed when experimenters no longer have a use for them.
Last year, the Government reported that more than 2.6 million scientific procedures had been conducted on animals in Great Britain in 2024. Millions more animals were bred but never used, killed as “surplus”, and left out of the headline figures. Regardless of what this week’s figures reveal, one fact remains unchanged: animals continue to suffer in laboratories across the country in the most horrifying ways.
Pregnant Mice Infected With Dangerous Bacteria
In one experiment, pregnant mice were anaesthetised while experimenters inserted a pipette into their vaginas and deposited a highly virulent strain of E. coli bacteria.
The infection spread into the womb and reached the unborn pups.
Many babies were born dead. Others were removed from their mothers’ wombs and decapitated so their organs could be dissected. Some newborn mice were injected through their skulls shortly after birth.
The infected pups developed severe inflammation and infection affecting the brain, lungs, and gut. At the end of the experiment, all remaining mothers and babies were killed.
Rats With Tubes Implanted Into Their Brains
Another project authorised the use of over 1,000 rats in experiments designed in an attempt to investigate memory and behaviour.
Experimenters were authorised to surgically implant tubes into specific regions of rats’ brains, so chemicals can later be injected directly into the brain to alter neural activity.
The animals will then be subjected to behavioural tests, including being forced to look for a hidden platform to escape from a pool of water and being deprived of food to induce food-seeking actions. Other rats will have electrodes inserted into their brains while under anaesthesia before being killed without ever regaining consciousness.
Every rat used in the project was scheduled to be killed.
Sheep, Cows, and Mice Deliberately Infected With Parasites
Another authorised project allows experimenters to infect dozens of cows and sheep with parasites.
Over 300 animals can be legally infected with parasites that can cause stomach pain, diarrhoea, dehydration, loss of appetite, fever, and reduced weight gain. In pregnant animals, infections may result in abortion.
The same project also involves infecting up to 180 mice, in whom the parasites can spread to the brain and alter behaviour.
Thousands of Salmon Subjected to Disease Research
More than 8,000 Atlantic salmon may be used in a project examining diseases affecting farmed fish.
The salmon will be kept in tanks and exposed to parasites, harmful algae, and microscopic jellyfish that can damage their gills.
Experimenters then subject them to stressful interventions, including freshwater flushing, elevated oxygen levels, and hydrogen peroxide treatments.
Hundreds of fish are repeatedly netted, weighed, measured, swabbed, and subjected to blood collection procedures.
Survivors will ultimately be killed.
Piglets Infected with Coronavirus
In another authorised project, 200 young piglets will be infected with a coronavirus.
Experimenters will sedate the animals and force them to inhale virus particles through a tightly fitted mask. They will then be vaccinated with experimental substances and repeatedly restrained while samples are taken from deep inside their noses.
The piglets may experience fever, breathing difficulties, diarrhoea, coughing, sneezing, exhaustion, weakness, and loss of appetite.
At the end of the experiment, they will be killed so their lungs can be examined.
Animals Are Not Numbers
When the Government’s figures are released this week, it will be tempting to focus on percentages and trends.
But statistics can never fully capture what animals endure.
These individuals are not data points. They are living beings capable of feeling fear, pain, and distress.
The Government has committed to ending the use of animals in science in all but exceptional circumstances. Yet millions of individuals continue to suffer every year.
When the new statistics are published, we’ll be examining whether the Government is making meaningful progress towards that promise.
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