ALTEX preprint published March 29, 2019 doi:10.14573/altex.1811061 1 Research Article Opportunities for Refinement in Neuroscience: Indicators of Wellness and Post-operative Pain in Laboratory Macaques 1 Kris A. Descovich 1,2,3 , Susan E. Richmond 1,4 , Matthew C. Leach 5 , Hannah M. Buchanan-Smith 1 , Paul Flecknell 6 , David A. H. Farningham 7 , Claire Witham 6,7 , M. Carolyn Gates 8 and Sarah-Jane Vick 1 1 Psychology, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom; 2 Environmental and Animal Sciences, Unitec Institute of Technology, Auckland, New Zealand; 3 Centre for Animal Welfare and Ethics, University of Queensland, Gatton, Australia; 4 Humane Slaughter Association. The Old School, Brewhouse Hill, Wheathampsted, United Kingdom; 5 School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne, United Kingdom; 6 Comparative Biology Centre, Newcastle University, Newcastle upon Tyne, United Kingdom; 7 Centre for Macaques, Medical Research Council, Salisbury, United Kingdom; 8 School of Veterinary Science, Massey University, Palmerston North, New Zealand Abstract Being able to assess pain in nonhuman primates undergoing biomedical procedures is important for preventing and alleviating pain, and for developing better guidelines to minimise the impacts of research on welfare in line with the 3Rs principle of Refinement. Nonhuman primates are routinely used biomedical models however it remains challenging to recognise negative states, including pain, in these animals. This study aimed to identify behavioural and facial changes that could be used as pain or general wellness indicators in the rhesus macaque (Macaca mulatta). Thirty-six macaques scheduled for planned neuroscience procedures were opportunistically monitored at four times: Pre-Operative (PreOp), Post-Operative (PostOp) once the effects of anaesthesia had dissipated, Pre-Analgesia (PreAn) on the subsequent morning prior to repeating routine analgesic treatment, and Post-Analgesia (PostAn) following administration of analgesia. Pain states were expected to be absent in PreOp, moderate in PreAn, and mild or absent in PostOp and PostAn when analgesia had been administered. Three potential pain indicators were identified: lip tightening and chewing, which were most likely to occur in PreAn, and running which was least likely in PreAn. Arboreal behaviour indicated general wellness, while half-closed eyes, leaning of the head or body shaking indicated the opposite. Despite considerable individual variation, behaviour and facial expressions could offer important indicators of pain and wellness and should be routinely quantified, and appropriate interventions applied to prevent or alleviate pain, and promote positive welfare. 1 Introduction Animals are currently used as bioscience research models and although primate use is a small proportion of total animal use, they are routinely subjected to procedures or conditions that directly and indirectly affect their welfare (e.g. Capitanio et al., 1996; Balcombe et al., 2004; Carlsson et al., 2004; Rennie and Buchanan-Smith, 2006a, b, c; Olsson and Westlund, 2007; Wolfensohn and Lloyd, 2013). It is a societal expectation that animals used in bioscience experience good welfare, which is characterised by an absence of unnecessary suffering (Lund et al., 2012; Leaman et al., 2014). Such considerations are also important for scientific validity as poor animal welfare may confound experimental results and affect the translation of scientific findings to human health benefits (Poole, 1997; Würbel, 2001; Tasker, 2012; Everds et al., 2013; Hall et al., 2015; Sneddon, 2017). To address these issues, animal use is guided in legislation and policy by the ‘3Rs’ principles of Replacement, Reduction and Refinement, which aim to replace sentient animals with non-sentient alternatives, reduce the number of affected animals, and minimise the impact of experimental procedures and promote welfare when non-animal alternatives are not available, respectively (Russell et al., 1992; Osborne et al., 2009; Prescott et al., 2010). In the 3Rs framework, Refinement is defined as “any approach which avoids or minimises the actual or potential pain, distress and other adverse effects experienced at any time during the life of the animals involved and which enhances their well-being” (Buchanan-Smith et al., 2005 pp. 379–380). The relative impact of some experimental protocols is species-dependent, for example social isolation (Dawkins, 2006a; Rennie and Buchanan-Smith, 2006b, c), however others, such as the experience of pain, are widely relevant to all sentient species (Bateson, 1991; Carstens and Moberg, 2000; 1 Received November 6, 2018; Accepted January 24, 2019; Epub March 29, 2019; © The Authors, 2019. ALTEX 36(X), ###-###. doi:10.14573/altex.1811061 Correspondence: Kris Descovich, PhD; Centre for Animal Welfare and Ethics, University of Queensland, Gatton, Australia (k.descovich1@uq.edu.au)