13 / 11 / 2023
Annual Statistics of Scientific Procedures on Living Animals in Great Britain 2020
FRAME welcomes drop in animal use from 2019 but more action is needed to drive change within a system still reliant on animal research.
The Home Office’s Annual Statistics report on the number of scientific research procedures carried out on animals in the UK in 2020 shows a 15% decrease from 2019. Whilst this is good news, the COVID-19 pandemic has undoubtedly impacted this decrease.
Here, we discuss the details of the report, highlight continuing trends, notable changes and any new insights these offer. In light of the report, we also consider the next steps to influence change in the continuing drive to move away from animal research.
Annual Statistics of Scientific Procedures: headline stats and trends
A total of 2.88 million scientific procedures involving live animals were carried out in Great Britain in 2020, down 15% from the 3.4 million in 2019. This is the lowest total number of procedures recorded since 2004.
These procedures can be split into those for experimental purposes (1.44 million) and procedures for the creation and breeding of genetically altered (GA) animals (1.44 million). Both figures are lower than 2019, but the roughly equal split between the two areas remains and indicates that high numbers of procedures are still required to create and maintain GA animal lines for research use.
92% of all procedures used mice, fish, and rats, a trend that has been sustained for the last decade. Mice remained the most used species, with over 2 million procedures being carried out.
The number of procedures on some species increased significantly in 2020, with 209,000 procedures using rats (up from 107,000 in 2019) and 11,300 procedures using rabbits (from 6,000). Procedures on cats increased by 11% to 146, and the number of procedures on dogs has increased by 3% to 4,300.
The number of procedures using fish has decreased to 275,000 (from 480,000) and procedures using monkeys to 2,400 (from 3,000).
What research purposes were animals used for in 2020?
The COVID-19 pandemic took hold across the world at the beginning of 2020, resulting in the first UK lockdown in March 2020. As a result of this lockdown, many workplaces shut as people were told to ‘stay at home.’ This stopped, or at least slowed, work at many research institutions and is the most likely explanation for the overall drop in procedures recorded. In the background, increased work on researching COVID-19 and developing vaccines may also play a part in the figures and possibly explain some of the trends seen in the regulatory testing figures and the species used. This is reflected in the slight decrease in the proportion of all areas of experimental procedures, except for procedures carried out for regulatory purposes. In 2019, 26% of all experimental procedures were for regulatory purposes, however in 2020 this increased to 33%.
Some laboratories may have redirected research or animals to investigate COVID-19, all under license from the Home Office, however the statistics do not contain any extra data to report back on animal use specifically for this purpose. You can read more about examples of animal use in COVID-19 research on Understanding Animal Research’s educational resource website here.
Where procedures typically take place has not changed significantly, with just over half of all procedures occurring in universities or medical schools (54%), 27% in commercial organisations, and 12% in non-profit making organisations such as disease research charities.

Basic research remains the area of research with the most recorded uses of animals at 53% of all experimental procedures (750,000 procedures). Basic research aims to increase knowledge of the structure, functioning and behaviour of living organisms and the environment. The main areas of interest were the immune system, nervous system, and oncology (cancer). These areas have remained broadly the same since 2014.
Mice are by far the most used species in basic research being used in around 562,000 procedures, rats in 45,220 and zebrafish in 101,000 procedures. These are also the top species used in applied research and regulatory research.
There were 1.44 million procedures for the creation and breeding of genetically altered (GA) animals, accounting for the other half of all procedures in 2020. Whilst this marks the first significant decrease in over a decade, the report does acknowledge that the drop in both procedures for the creation and breeding of GA animals, and the use of GA animals in experimental procedures, is most likely due to the two UK lockdowns in 2020. 90% of procedures were carried out to maintain established GA lines and the remaining 10% to create new lines. You can read more about the use of GA animals in research in our blog here.
All procedures are classified by their severity – that is the likelihood they will cause pain, suffering, distress or lasting harm. The proportions of severity of procedures have remained similar to previous years with 51% of procedures classified as causing ‘mild’ suffering, 24% moderate and 4% severe.
Read more about definitions of research uses and the severity of procedures here.
Where do we go from here?
When looking at the species used in these reports, it must be noted that the figures include all types of research including regulatory testing for veterinary products, research into animal health and disease, and environmental research for the benefit of animals. At FRAME, we are striving to end the need for animal testing in all areas, but our primary focus, and the areas where we feel non-animal methods are, or will be, more relevant, is testing for the benefit of humans. This might include for example, regulatory tests for chemical and drug safety, efficacy, basic and applied research linked to human biology and health.
The statistics show that genetically altered (GA) animal use still accounts for many experimental procedures, in spite of the 26% decrease in their use from last year – the first drop in over five years. Procedures carried out for the purpose of creating and breeding GA animal remain high, half of all procedures (1.44 million) were for this purpose. Whilst the Annual Statistics provide insight into where and how animals are used, the data tables do not provide a breakdown of numbers of GA animals vs non-GA animals used in specific areas of basic and applied research. This information would be a useful addition to help understand the areas where GA animal lines are being used most frequently and help channel the development of alternatives and sharing of information to influence a move towards more human-relevant, non-animal methods. You can read more about the drivers, benefits and concerns of GA animal use in research in our blog here.
Whilst the drop in procedures in 2020 is a positive move, and is a continuation of the fall in procedures seen in previous years, we cannot attribute it to a move towards alternatives due to the impact of the pandemic. What we do know is that, as in previous years, testing on animals for basic, applied and translational research is by far the biggest user of animals. Although animal testing for regulatory purposes is in the public eye more often, it is an area where we are perhaps closed to replacing animals due to a structured regulatory system which incorporates the identification and validation of alternative, non-animal methods which are then set out in guidelines. This is unlike basic and applied research, where the identification and use of alternatives is much more open-ended and down to the individual researcher to find, evaluate and choose over the use of animals. It is difficult within this non-regulatory system to judge whether the 3Rs have been effectively applied, and whether there is in fact a way of researching a question without animals, coupled with the popularity of GA animal lines, which are sometimes of value in providing useful discoveries, but in many cases are not. As well as this, it is difficult to judge the value of animal research in a system where only published or publicly available research can be evaluated.
In 2010, the UK government made a commitment to put the 3Rs (Replacement, Reduction and Refinement) at the heart of scientific research and published the document ‘Working to reduce the use of animals in scientific research’, followed by a roadmap to help progress non-animal technologies in the UK. But very little has changed.
This year, animal welfare organisations have been calling on the government to act. The introduction of the Animal Welfare (Sentience) Bill as part of the government’s Action Plan for Animal Welfare is a step in the right direction, however, this action plan does not include any plans to further address the use of animal in research, with animals categorised as pets, sporting animals, farming animals or wild animals.
This year, Animal Free Research UK published a report ‘Modernise Medical Research’ with a call to action for the government to create a new department or ministerial position to exclusively look at accelerating the replacement of animals. The RSPCA has also recently published a report in light of a discussion panel held with experts from across the animal research and alternatives fields. The report, ‘Could we achieve a phase-out of animal experiments in the UK’, considers how close we are to ending animal research and identifies actions they may help drive a phasing out of animal experiments in different areas.
It is clear that bold moves may be needed to accelerate change. Whether this is driven from a government and policy level or from within the current system of funding, regulating and publishing of animal research. This might involve setting end dates for animal use in specific tests or a blanket public registration platform for the sharing of all animal study outcomes. On the ground level, the current research system is still flawed and set up to view animal research as the gold standard, with non-animal methods often not valued without a comparison with animal data. In order to facilitate a change where important medical research is not compromised, animals must be seen as a last resort to answer questions about human health and disease by the whole research community. Where they are still necessary, we must divert time, funds and support to understand what technology and techniques are needed to answer those questions – without animals.
As a world leader in animal welfare and scientific research, the UK government is in a prime position to help make this change.