What is Severe Suffering

Any level of suffering is obviously a concern for everyone, but tackling severe suffering should be a top priority.

Within the European Union, a prospective severity classification (PDF 192KB) is assigned within the project evaluation (PDF 1.33MB) process. 'Severe' procedures are those 'as a result of which the animals are likely to experience severe pain, suffering or distress, or long-lasting moderate pain, suffering or distress. Procedures that are likely to cause severe impairment of the wellbeing or general condition of the animals'. Similar classifications are used in other countries such as the US ('E') and Canada ('D' or 'E').

Severe suffering may be experienced as physical pain, psychological distress, other physiological stressors such as 'air hunger' (dyspnoea) or severe feelings of 'sickness' or nausea. Whatever the nature of the suffering, reducing or avoiding this significantly reduces harms to animals, which will help to fulfil legal requirements, reduce ethical concerns and improve the harm-benefit balance. Better animal welfare also leads to better quality science; for example, untreated pain or distress can lead to physiological alterations that can increase variability and confound the data.


Reducing severe suffering would be impossible without support and information from scientists in relevant fields.

Sharing information about refinement, within publications, presentations and by sitting on expert working groups, will increase your research impact and help to ensure better science and animal welfare - in your own field and others. Your input is also essential in helping to ensure that approaches to reducing and avoiding severe suffering are feasible, supported scientifically and do not lead to animal wastage by introducing experimental confounds.

Animal technologists and vets

Animal technologists and veterinarians are integral to the success of strategies to reduce suffering.

They are heavily involved in identifying new approaches to refinement and welfare assessment, as well as caring for animals and assessing their welfare on a day to day basis. Their knowledge of the biology, behaviour and welfare needs of the study species is also invaluable in helping to understand and alleviate harms to animals. You can bring important perspectives to bear and help to ensure that every opportunity to reduce suffering is identified and acted on.

AWERB members

Several of the AWERB's tasks are directly relevant to tackling severe suffering, for example those relating to advising on the application of the Three Rs; advising on matters relating to animal welfare; following the development and outcome of projects; and supporting named persons and other staff.

Whatever your role on the AWERB, or level of experience, you can contribute to reducing or avoiding severe suffering.