The Concordat on Openness on Animal Research has recently been launched with 72 signatories across the UK academic & corporate biomedical research world, including the University of Oxford. The plan is to try to improve the public understanding of animal research in the hope to sway them away from the animal rights (AR) position of complete opposition. The Concordat will not satisfy the AR activists because it is voluntary and because some AR activists are so ideologically opposed that they would rather people be permanently disabled or die of disease or drug side-effects than have animals be experimented upon. Indeed, AR extremists have been known to use violence against individual working on animal research, to the extent that all members of relevant departments at Oxford are notified whenever a large protest is organized and additional security is provided. However, the Concordat might convince moderates who want to both have medical research and prevent unnecessary harm to animals to hold more reasonable expectations.
In the spirit of openness and to debunk some of the proffered alternatives (testing on prisoners, computer simulations, cells in a test-tube). I shall explain some examples of when, how, and why research on animals is performed.
(1) Animal models of disease
Animal disease models are the most common use of animals in biomedical research. Most commonly it will be mice or rats which have been genetically modified to simulate the genetic alterations found in human patients with the disease. They are used to both understand the progression and pathology of the disease as well as an early stage test of therapeutics. The benefits of using animals are: a) that experiments are repeatable because the animals are inbred so they are genetically identical and all carry the same genetic variant associated with the disease, b) long-range disease processes can be examined eg. cancer metastasis, interactions between muscle and pancreas in diabetes, c) behavioural symptoms can be examined eg. Parkinson's walking difficulties d) examination of all tissues at different stages of the disease (even before the mice show symptoms).
Many diseases are impossible to study in living humans, either because it is difficult/dangerous to get samples (eg. anything involving the brain), or because some form of treatment already exists so it is unethical to deny them treatment (eg. cancer), or because by the time they are diagnosed most of the disease process has already happened (eg. type-2-diabetes), or because it is sufficiently uncommon or variable that it is impractical to find enough willing patients that are the same.
Depending on the disease other animals which more closely resemble humans may be used. Eg. ferrets are used for studying flu, rabbits are better models of the heart, and chimps are used to study hepatitis C because they are the only other animal known to be susceptible.
(2) Animals in basic research
Basic research is interested in how normal biological systems work. It provides the background upon which hypotheses of how diseases come about can be based eg. understanding how cells divide is crucial to understanding cancer. Most commonly it is mice and rats used in experiments. However, studies of cognition may use more cognitively complex & social animals (apes, birds) if non-humans are required (I would note that typically it is easier to experiment on humans than apes because the former can provide informed consent). Because of the broadness of topics examined by basic research it is hard to generalize about how animals are used; some possible uses are: genetically modified animals with a gene can be turned on/off to examine its effect during development and adulthood (eg. figuring out what a key developmental gene does in an adult), extracting a fully functioning organ (after sacrificing the animal) to examine its structure and function (eg. mapping connection in the brain), tracking inheritance of various molecular characteristics and traits (eg. is stress inheritable?).
(3) Animal testing
I have separated animal testing, which I will define as testing for toxic effects of a chemical or product, from other forms of animal research because it is most commonly performed by large private companies to meet government mandated health and safety standards. However, ecological toxicology testing (eg. testing water pollutants for effects on amphibian birth defects) is often done by independent academics before governments take action. Animal testing is generally the most despised form of animal research and is typically the only kind the general public is aware of (thanks to AR publicity). It is important to point out that companies would prefer not to do the testing since keeping and looking after hundreds of mice and rats is expensive but are required to do so to protect consumers (aka the public) from hazardous products.
Alternatives to some of these tests are being development both using computer simulations and using cells or tissues in a dish (eg. liver toxicity of drugs can be tested on liver cells in a dish or predicted from result from similar drugs). A couple of these alternatives have reached an accuracy sufficient for the regulatory bodies to accept them as an alternative to testing on animals. However, we can only design and test alternatives for toxicological effects we already know a lot about and only when they are not too complex; for instance we would not be able to check for the propensity of a drug to cause birth defects or seizures using anything less than a whole mammal.
So while efforts are on going to create animal-free substitutes for the most commonly performed tests and researchers are usually required to demonstrate that they are using the minimum animals necessary in their experiments it is unlikely we will ever be able to completely eliminate animals from research.
Addendum: An interesting follow on to this article is that the NIH (USA biomedical research funder) has announced a new policy requiring scientists to include both male and female animals in all of their research to look for sex-differences in disease and drug response (traditionally only males are used). The justification being that women experience significantly more drug reactions than men and many non-infectious diseases have sex-biased effects (eg. women are more susceptible to auto-immune disease while men are more susceptible to neurological disease). The effect of this policy will likely see an almost doubling of the number of animals being used in research.
