Animals have aided us in the development of new cures and drugs but, as recent reports have indicated, they are poorly treated despite this important role, writes Alison Lee
If you were born prematurely, you were given a dose of steroids to help speed up your lung development. If you’ve been in an accident and lost blood, chances are you were rushed to hospital and given a transfusion that matched your blood type.
If you’ve ever had an operation, be it as simple as wisdom tooth removal or as complex as open-heart surgery, you were safely anaesthetised, virtually eliminating all pain and distress. It’s easy to take these lifesaving innovations for granted, but it’s a fact that none of them would exist without animal testing.
Research on premature sheep and rabbits has increased survival rates of premature babies. Studies on Rhesus monkeys revealed that human blood cells are either ‘rhesus positive’ or ‘rhesus negative’ allowing us to give safe blood transfusions.
Animals are also being used to research currently incurable diseases, and immense progress has been made in understanding conditions like breast cancer, HIV and muscular dystrophy. The vast majority of mammalian species used in these studies are mice and rats. In 2009, 209,903 mice and 16,198 rats were used in Ireland for research purposes.
Strains of inbred mice have been created by generations of brother-sister mating, which result in mice that are almost genetically identical – ideal for carrying out experiments on, as there is hardly any variation between test subjects. These are used to create ‘models’ of human disease.
Models can be created surgically, for example, mouse models of arthritis commonly have ligaments in their limb joints damaged. Breeding can also create models while mouse genetics can also be manipulated artificially to create models of disease.
Such procedures may horrify some readers, but this sort of research on rodents is commonplace in laboratories all over the world. Contrary to what extremist animal rights organisations like PETA would have us believe; scientific research on animals is not necessarily a ghoulish process carried out by money-hungry pharmaceutical corporations.
This is because strict legislation governing animals used in research is in place. Ireland’s current legislation was set down by the European Union in 1986 in the (86-609-EEC Directive), and Ireland implemented this legislation through the 1876 Cruelty To Animals Act.
Thanks to these laws, anyone wishing to carry out experiments on animals must receive a license from the Department of Health and Children permitting them to do so. Applicants for these licenses must use the minimum number of animals possible, they must design their experiments to avoid any unnecessary pain or suffering and they must use anaesthesia on animals during all potentially painful procedures.
In addition, rules have been laid down outlining the requirement for anyone working with animals to be adequately trained, for veterinary care to be available if necessary, and to ensure an adequately high standard of housing and care of experimental animals.
Sadly though, there is evidence to suggest that sometimes, animal testing may not be as useful as its made out to be. Many animals’ lives are lost merely to follow protocol and considering how many drugs fail to make it to human trials, never mind to the pharmacy shelves, some animals’ lives are lost for nothing.
Take for example, the gastritis treatment Omeprazole. At first, this drug wasn’t allowed onto the market, as it caused stomach cancer in the rodents it was tested on. But due to fundamental differences between the physiology of rodents and people, Omeprazole doesn’t have this effect on humans.
Once this was proven, Omeprazole went on to become the biggest-selling drug in history. It’s also important to remember that mouse models only display the symptoms of the disease they mimic. The underlying cause of the disease in humans may be completely different to that in lab animals.
Take the mouse models of arthritis previously mentioned – humans don’t develop arthritis by having their ligaments surgically severed – the causes of arthritis in humans are manifold and include ageing, genetics, and exercise. Also, mice are tiny, four-legged creatures who move differently to humans and have differences in their cartilage biology. This is just one example of models that only superficially mimic human disease.
And although there is legislation in place to ensure animals are not used unnecessarily or put through extraneous pain or suffering, there is a lack of clarity as to how the animals should be kept.
One line in the 86-609-EEC Directive has a particularly depressing ring to it: “Member States shall ensure that…all experimental animals shall be provided with housing, an environment, at least some freedom of movement, food, water and care which are appropriate to their health and well-being.”
The term “at least some freedom of movement” doesn’t bring to mind images of particularly stimulated, happy animals. And sadly it tends to be rodents, the most commonly used animals in research, that receive the bare minimum in terms of environmental enrichment and stimulation.
This is possibly due to a phenomenon known as the ‘socio-zoological scale’, a subconscious hierarchy that humans assign to animals. For example, many of us see companion animals like dogs, or valuable animals like horses at the top of this scale, useful animals like cows, sheep or pigs somewhere in the middle, and then creatures traditionally seen as pests at the very bottom.
This is reflected in experimental animal legislation, where special protections are applied to dogs, cats, and equids used in research. Dogs, cats or horses don’t feel fear, distress or pain any more than a mouse or a rat, but this double-standard still exists, meaning the species we owe the most to in terms of drug development is the species that is the most neglected.
Drug companies and research facilities have responded to calls for less animal testing with the three R’s: Replace, refine and reduce. This means they aim to reduce the number of animals used in research, to replace them with alternative non-animal tests where possible, and to refine experiments, causing less distress to animals.
To this end, The European Council for the Validation of Alternative Methods (ECVAM) was established. This body validates non-animal tests, which can replace tests on animals – but only for cosmetics, not drugs. For example, artificial skin has been developed which can be grown in the lab and used to test chemicals for skin irritancy, instead of applying chemicals to the skin of live animals.
These tests have gone a long way in reducing animals used in cosmetic research, but changes are slow, especially since it takes years to ensure “alternative” tests are as valid as their counterpart animal tests. Also, considering the number of mice used in research in Ireland rose from 18,535 in 1994 to 209,903 in 2009, it seems that an excessive amount are being utilised of late.
It would be naive to say that animals are unnecessary for drug development. Drugs must be tested in animals before human administration to gauge what organs might experience side effects, or what the correct dosage is.
But considering the fundamental differences between humans and rodent biology, scientists need to think long and hard about the reasons behind using rodents in research. Just because they are traditionally seen as vermin doesn’t mean their lives in a lab should be monotonous, devoid of the simple pleasures that owners lavish upon their pet rodents without a second’s thought.
They are sentient beings capable of feeling pain, fear, distress and boredom. Surely the least we can do for creatures that have indirectly saved so many lives is to acknowledge this, and treat them as such.