Animal Experiments in Research

Last update: June 2010
Contact: Thorsten Galert

Authors

I. The importance of animal experiments for research

Number of laboratory animals: Germany and Europe

Animal experiments are conducted, inter alia, to investigate physiological processes, develop products and therapeutic techniques and verify product safety.

The Animal Welfare Report (Tierschutzbericht) (see module Animal Welfare Report) documents 2,265,489 test animals in 2004. In 2005 2,412,678 animals were used for experimental purposes in Germany, in other words an increase of some 147,000 animals. Most recent data also document an increase up to 2,692,890 test animals in 2008. Europe-wide too, the number of laboratory animals has risen in recent years. The COM Report (see module COM Report) put the number of vertebrates used for scientific purposes in Europe in 2005 at around 12.1 million; this means that roughly 1.4 million more animals were used in 2005 than in 2002. Taken together, mice and rats constituted - both in Germany and in Europe as a whole - the largest group of laboratory animals (approx. 80%), followed in second place in Germany by fish (around 7%), with rabbits coming in third (roughly 5%). Non-human primates (see module Non-human Primates) constituted 0.1 % of all laboratory animals. Since 1991 anthropoid apes (chimpanzees, gorillas, orang-utans) have not been used for experimental purposes. Nor were any experiments performed on anthropoid apes (see module Human Rights for Anthropoid Apes) in the member states of the European Union in 2002 and in 2005.

In various areas (for example in toxicological tests) the numbers of laboratory animals are declining. In basic research, however, the number of test animals has been on the rise again for some years now. The increase is attributable in particular to the growing use of transgenic mice (see module Transgenic Mice).

Alternative methods

Animal experiments can be replaced with alternative methods (see module Alternative Methods) in a variety of areas. For example, numerous experiments are currently performed on cell cultures. By way of differentiation from experiments on living organisms (in vivo) such "test tube" methods are referred to as in vitro. Computer simulations may also serve as a substitute for the use of laboratory animals, since they help to predict how substances will act on the body. The extent to which alternative methods may replace animal experiments in the near future is a matter of some controversy. At least in the field of cosmetics research (see module Cosmetics Directive), it is envisaged that safety testing on animals will be completely replaced by alternative test methods. Researchers point out, however, that in the future it will still not be possible to entirely do away with animal experiments - especially when it comes to testing pharmaceutical products: the complexity of an intact organism is necessary in order to verify all the effects of a substance. In the fields of neurobiological fundamental research and of research in infectious diseases, for instance, research with non-human primates is still irreplacable at the current moment, according to several researchers (see module Non-human Primates).

Applicability of the results of animal experiments

It is only since the advent of the modern era (see module Modern Era) that animal experiments have been conducted on a significant scale. Since then a broad-ranging debate has raged on the acceptability of animal experiments. From the very outset of the debate, opponents of animal experiments have asserted that the insights yielded by animals cannot be applied to humans and are therefore largely useless. This criticism is directed both at the findings of basic research (e.g. the "mouse model") and at the results of drug tests performed on animals (see Section II). At issue was - and still is - the question of whether different species (such as human and mouse) react to the same substances in the same way on account of the structural and functional similarity of many organs or whether the effect of substances on organisms is more heavily species-specific. Were the latter to be the case, animal testing of substances would, for example, offer only an illusory sense of safety. History lends support to both standpoints: on several occasions the results of animal experiments have misled scientists into formulating incorrect research hypotheses (e.g. in research into poliomyelitis (polio) (see module Poliomyelitis) or lulled them into a false sense of security when testing product safety (as in the case of Contergan (thalidomide)) (see module Contergan). In other cases the effects observed in animal experiments did prove to be applicable to humans. The German Research Foundation (Deutsche Forschungsgemeinschaft = DFG), the central self-governing organisation that promotes research in Germany, estimates that animal experimentation can predict "desirable and roughly 70% of undesirable effects on humans" (DFG (2004): Tierversuche in der Forschung. Bonn: Lemmens Verlags- und Mediengesellschaft, 2004: 18).

Next: II. Legal aspects of research on animals