Implementing the 3Rs: improving experimental approaches in animal biology.

The pages of this journal are full of remarkable stories of scientists working with extraordinary and commonplace creatures to understand how these species survive and interact with their environment. None of these studies could have been undertaken without the contributions of the central protagonists themselves, and in the fields of biomedical research and ecotoxicology, large numbers of vertebrate model organisms contribute to our understanding of disease and the impact of pollution in the environment. With recent rapid changes in climate and the degradation of many environments, animal research has never been more significant. However, this expansion has been accompanied by increasing awareness of the welfare of the animals that contribute to our growing knowledge and a rising appreciation of the three Rs (3Rs) – replacement, reduction and refinement – which underpin the ethical use of animals in research. Having previously organised a successful meeting in 2012 dedicated to the implementation of the 3Rs with the National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs), Lynne Sneddon from the University of Liverpool, UK, says that she and Nic Bury from King’s College London, UK, felt that it was time for the Society for Experimental Biology (SEB) ‘to showcase the state of the art in 3Rs science and to educate our membership to give them opportunities to employ the 3Rs in their research’. Collaborating with the NC3Rs, Sneddon and co-organiser Bury coordinated the ‘Improving Experimental Approaches in Animal Biology: Implementing the 3Rs’ meeting at the SEB headquarters in London over three days in late June 2016. Inviting speakers from a broad spectrum of laboratories to present examples of best practice and to discuss the promotion and education of the 3Rs, Sneddon and Bury structured the first day of the meeting around case studies dedicated to the refinement of procedures involving animals. ‘The whole reason for the 3Rs is to improve welfare, make animals healthier and fitter, to use fewer of them, thereby improving the quality of the data’, says Sneddon, emphasising that the purpose of refinement is to develop and use the most humane and non-invasive methods, where traditional methods may have previously been more intrusive. With some approaches focusing on improving the welfare of more traditional laboratory animals, such as zebrafish, mice and Xenopus, other presentations reviewed the assessment of pain in ball pythons and the effects of morphine on the South American rattlesnake. In her Association for the Study of Animal Behaviour prizewinning talk, Lottie Hosie from the University of Chester, UK, reported on refinements in laboratory husbandry in African clawed frogs (Xenopus). Although Xenopus is one of the major model animals and has been reared in laboratories since the 1940s, little is known about the best conditions for keeping this species in captivity. In their native environment, Xenopus inhabit dark, muddy lakes and rivers, in contrast to the barren environments that they occupy in laboratories, and Hosie has been investigating ways of enriching the animals’ environment to reduce stress. ‘We have developed non-invasive tools, one of which is an assay for corticosterone, which is the amphibian stress hormone... and alongside that we are developing behavioural tools so that we can also assess behaviour as a welfare monitoring tool’, says Hosie. She adds that providing plastic refuge tubes and shelters leads to measurable welfare improvements for the animals. In a separate presentation, Matthew Leach, from Newcastle University, UK, reported his assessment of the expression of pain in animals through observation of facial grimaces, which he has developed as an alternative to other more costly and time-consuming approaches that have traditionally been used. Focusing on the three main rodent models – rat, mouse and rabbit – Leach’s observations have been rolled out in a series of posters (https://www.nc3rs.org.uk/ grimacescales) distributed by the NC3Rs to raise awareness of the grimace scales and their utility for assessing the degree of pain experienced by an animal, allowing researchers to deliver pain relief more rapidly to improve welfare. While refinement has clear and direct benefits for animals used in research, the replacement of vertebrates with alternative systems – from cell culture to invertebrate models – offers great potential to reduce the numbers used in experimentation. With a broad range of presentations – from the use of the social amoeba Dictyostelium discoiduem to assess the health benefits of dietary flavonoids, to the use of paired-down memory circuits in the pond snail Lymnaea Fig. 1. Craig Franklin with the ASAB prize winner, Lottie Hosie. Photo credit: SEB.