Naturewatch briefing on the Three Rs

 Why refine?

Of all the 3Rs, refinement is the one which receives the most criticism. Giving a laboratory mouse nesting material, it is argued, does not tackle the real evil of the mouse being in a laboratory in the first place. However, there are real reasons for taking refinement seriously: we look at several of them.

• While animal experimentation is still taking place and there is no immediate likelihood of its ending, the welfare of the animals currently in the laboratories should still be a matter of concern. A significant shift in policy regarding environmental enrichment (whereby animals are given things like nesting materials, toys and chewing blocks) could affect every laboratory mouse in the UK, whereas a replacement of an animal experiment with a non-animal alternative may affect only a few.

If animals live close-to-normal lives in laboratories by shrewd use of environmental enrichment, the scientists themselves are more likely to treat them well and less likely to treat them as laboratory tools. Furthermore a well-maintained mouse is likely to yield better data for the scientist: this is potentially a win-win solution that improves animal welfare and science at the same time. The political reality is that the vast majority of legislators do not believe in animal rights, although they may take animal welfare seriously. They may therefore be very concerned about experiments which appear to be excessively cruel, but may regard experiments in general as a necessary evil. Therefore they may be receptive to ensuring that procedures that produce substantial suffering be considerably refined.

"This enrichment is advertised as a wooden chewing block, but its design allows it to also be used as a nest/shelter (the mice drag paper into it), and a climbing object." - image and text © Chris Sherwin in 'Comfortable Quarters for Laboratory Mice'.

• Refinement also involves replacing species with ones that are deemed to be less advanced. Public concern is particularly great where monkeys are used, and these may sometimes be able to be replaced by mice. Much greater refinements may be possible if rats and mice in some procedures can be replaced by nematode worms: it would be hard to argue that a nematode worm can consciously suffer in the same sense that a mouse can. More...

• Some refinements may improve the quality of the science. Some strains of mice have been genetically modified so that tumours within them glow. Their growth can be monitored non-invasively, whereas before the only way to monitor tumour growth was to breed many more mice and systematically kill a certain number after a given time interval. Far fewer mice need therefore be used while the science improves substantially. More...

We can be idealistic and demand only that replacements be developed. Meanwhile, millions of animals die each year, with their welfare needs unmet – in part because we demand something that is unrealistic in the present political climate. Refinement does not solve the problem of animal experiments, but it can lead to massive gains for animal welfare. By so doing it enables scientists to focus more on the needs of the animals in themselves and not just as laboratory tools, and this is a vital part of changing the culture of the experiment industry.

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