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Painful dilemmas: the ethics of animal-based pain research

Published online by Cambridge University Press:  01 January 2023

M Magalhães-Sant’Ana*
Laboratory Animal Science, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal Department of Veterinary Sciences, University Vasco da Gama, Quinta de S Jorge, Estrada da Conraria, 3040-714 Coimbra, Portugal
P Sandøe
Danish Centre for Bioethics and Risk Assessment, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 25, 1958 Frederiksberg C, Denmark
IAS Olsson
Laboratory Animal Science, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal Danish Centre for Bioethics and Risk Assessment, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 25, 1958 Frederiksberg C, Denmark
* Contact for correspondence and requests for reprints:


While it has the potential to deliver important human benefits, animal-based pain research raises ethical questions, because it involves inducing pain in sentient beings. Ethical decision-making, connected with this variety of research, requires informed harm-benefit analysis, and the aim of this paper is to provide information for such an analysis. We present an overview of the different models and their consequences for animal welfare, showing that, of the many animal models available, most have a considerable welfare impact on the animal. While the usual approach to pain control through administration of analgesic substances is usually unsuitable in pain research, refinement remains an option, both within the experimental protocol and in general husbandry and handling. Drawing on the overview, we develop a discussion of the ethical acceptability of animal-based pain research against the background of the kinds of harm done to the animals involved, the potential for refinement, and the expected benefits of the research.

Research Article
© 2009 Universities Federation for Animal Welfare

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