© Nuffield Foundation 2011 Are animal experiments painful? What might lead to pain and distress in an animal used in experiments? Do you think animals experience pain and distress in the same way as humans?

© Nuffield Foundation 2011 The law divides experiments into four classes: Mild: slight adverse effects, e.g. taking blood samples Moderate: includes injections that cause a reaction and many surgical procedures, provided that suffering is controlled by effective pain relief and care Substantial: includes major surgery and testing chemicals which cause a significant level of pain or death Unclassified: when animals are put under anaesthetic before the experiment and are killed before they recover consciousness Are animal experiments painful?

© Nuffield Foundation 2011 An experiment that uses many animals but does not cause much pain or distress? or An experiment that uses one or two animals but is very painful? Which is worse?

© Nuffield Foundation 2011 Number of projects at each level of severity in 2005

© Nuffield Foundation 2011 How many experiments in the UK are mild, moderate and substantial? We don’t know. We only know the numbers of mild, moderate and substantial projects, which is an average of many experiments e.g. 100 mild experiments + 10 substantial experiments = a moderate project Is this enough information?