By Charlotte King
Recent scientific research suggests that enriching laboratory enclosures could improve the quality of scientific results. There has been a long-standing consensus to standardise enclosures for lab rodents, by limiting the number of variables in their environment. Therefore, until recently all laboratories have prioritised small, cheap and sterile enclosures. This was to ensure that studies involving lab animals are as reproducible as possible, maximising the legitimacy and accuracy of results.
Today many lab animals live in shoebox-sized cages. Each enclosure is overcrowded to maximise the number of tests being conducted, meaning these animals are often unable to even stand upright. Recent research conducted by the University of Michigan however suggests that whilst living in these barren-style enclosures, lab animals experience stress which may lead to inaccurate test results. Studies suggest that, on average, out of the 9 drugs which test successfully on lab rodents, only 1 of those 9 succeeds in human trials.
Joseph Garner, who runs a laboratory in California, says: “we’re trying to control these animals so much, they’re no longer useful”. He is one of the many scientists who is advocating that happy lab animals are better for science. At the University of Michigan researchers are beginning to provide lab rodents with enriched enclosures, filled with toys and space to explore, because it is believed that when they live a better life they make better research models and produce more accurate test results. Therefore, there is a rising number of scientists who are encouraging more spacious, less crowded enclosures to stimulate the brain.
There is evidence to support this movement. In 1947, Donald Hebb discovered that his rats whom were allowed free rein at home were better at learning than rodents in a laboratory setting. This was one of the first indicators that enriching the environment for lab animals could provide better test results. Since then, researchers in Australia have found that when in enclosures with ropes, toys and ladders, rodents are slower at developing a Huntington-like disease. Research has also proven that when lab animals live with mazes and wooden blocks, the sensory regions in their brains grow larger than if they did not have these enriched enclosures. Moreover, enrichment may also reduce the likelihood of these rodents suffering epilepsy, addictions and multiple sclerosis. Some scientists are arguing these benefits will lead to more accurate scientific results and conclusions because the animals can cooperate better within the studies.
However, other scientists argue that enriching enclosures to provide these animals with comforts will compromise scientific study. Jonathan Godbout, a neuroscientist at Ohio State University, says there is “nothing natural” about these enriched environments and they make it more difficult to reproduce studies as it is hard to replicate the exact surroundings. Therefore, it is more challenging to ensure if results are accurate. There are also concerns regarding budgeting – enriching enclosures is costlier than using the standardised cages. Godbout fears that this will use up money which could otherwise be spent on animal testing, therefore scientists will be unable to produce as many results.
However, research has proven that lab animals live mentally complex lives, and experience a range of emotions just like us. Their reaction to stress parallel the human reaction to stress, wherein it can boost the risk of cancer and other illnesses. Scientists are therefore arguing that these similarities suggest a need to treat these animals more like humans to gather more accurate results, which could better translate to human health. Neuroscientist Anthony Hannan says that by allowing lab animals to live better lives, “less research could be done, but it would be better research”.
It is evident there is a growing movement forming which promotes the enrichment of the lives for lab animals. In the early 2000s, only a handful of academics were discussing the benefits of enriching enclosures. Fast-forward to 2016 however and over 160 academic papers were published on animal enrichment. Whilst the proposal may be more costly than current methods of care, more and more scientists are advocating that happier lab animals are better for science. Lofgren sums it up as “they’re giving us the best they can. So we should be doing the best we can”.