UK Statistics

Different colours represent changes to the counting method in 1987 and 2014.

The trend over time in animal experiments in the UK. Click to Enlarge.

Every year the Home Office releases the statistics on animal research in Great Britain (Northern Ireland released separately) for the preceding year. In 2015, the total number of procedures on animals was 4.14 million, up 7% from the  3.87 million in 2014. However, the UK Home Office has warned that quality issues with the 2014 data (the first year under a new counting methodology) mean it is likely that the 2014 numbers were under-reported.

The total number of animals was slightly lower, at 4.07 million, as some animals were used for more than one procedure*. In 1987 the UK changed the way in which it counted animals, from the total number of animals to the total number of procedures.The statistics for Northern Ireland are not included and we have provided more details at the bottom of the page (22,508 procedures in 2015).

*The total number of animals excludes those animals first used in a previous year, which underwent a procedure in the current year, in order to prevent double counting of animals between years.

The last few years has seen the number of Genetically Altered animals (mainly GA mice) being bred rising as a proportion of all studies; this accounts for 49.8% of all procedures (in 2015).Other common uses included basic research (26.6%), regulatory purposes (13.4%) and translational/applied research (9.7%).

Total Procedures by creation of genetically altered animals and experimental procedures

Looking at the species used we can see, mice, rats, birds and fish account for over 96% of all procedures on animals in Great Britain. Dogs and cats account for 0.12% and primates account for around 0.09%. Invertebrates such as fruit flies and nematode worms are widely used by researchers but are not covered by the Animals (Scientific Procedures) Act and are thus not included. The only invertebrate included in the statistics are cephalopods, though none were used in 2015.

animal experiments in the uk in 2015 by procedures

Procedures on animals in Great Britain for research in 2015. Click to Enlarge

For the second time, the UK statistics include retrospective reporting of suffering. Rather than just submitting licence proposals to the Home Office that include estimated levels of suffering, the researchers now have to report on what was actually seen (using a variety of measures). Unfortunately, the statistics put these in two separate tables (Table 3 and 8). So we have combined them to get severity for all procedures in 2015. We can see most experiments are sub threshold (34%; less than the introduction of a hypodermic needle) or mild (45%), with remainder as moderate (14%), severe (4.5%) or non-recovery (3%; the animal never awakes from anaesthesia). Of the experimental procedures, two-thirds in the severe category were regulatory procedures on mice; this is often because death is an endpoint in such procedures. Overall the proportion of moderate and severe fell from 19.2% in 2014 to 18.2% in 2015.

Animal research severity in research and breeding in Great Britain in 2015

Severity of animal research in the UK in 2015

It is also important to realise that no animal research or testing was done for:

  • Tobacco products (banned in 1997)
  • Cosmetic products (banned in 1998)
  • Household products (banned in 2015)



When we look at the other uses of animals in the UK we see that those killed for medical research (and the huge benefits that go with it) are far outweighed by the numbers of fish and chickens eaten, and even by the number of birds and other wildlife killed by domestic cats.

Finally, it is worth remembering the huge benefits brought about by animal research. Here are some  annual figures of treatment used that were developed through animal research.


Table sources:

UK Statistics Sources:
Speaking of Research Report on 2015 statistics:
Home Office reports 2001-2015:

Animal Research in Northern Ireland

In Northern Ireland, animal research statistics are compiled by the Department of Health, Social Services and Public Safety in Northern Ireland (as opposed to the UK Home Office, as in England, Scotland and Wales).

Animal research in Northern Ireland accounts for much less than 1% of the total animal research in the UK. In 2015 the number of procedures was 22,508, up 13% from 2014.


Since the number of procedures involving the creation and breeding of GM animals is much lower than in the UK (and these are often sub threshold), the proportion of sub threshold procedures is much lower than the rest of the UK. The number of severe procedures is similar to the rest of the UK, but there is a higher proprtion of moderate severity procedures.



Animal Research statistics of Northern Ireland, 2005-2017: