Animal research at the Max Planck Institute for Metabolism Research

Excessive weight is an escalating burden for our society. According to the German Federal Statistical Office, more than half of the people in Germany are overweight. As a result, the number of diabetes and stroke patients is rising dramatically. This alarming development shows how important metabolism research is. Only a comprehensive knowledge of the mechanisms that allow body weight to be kept constant, can be the basis for defining their malfunction in the development of the disease in order to ultimately develop new therapies for these widespread diseases. Therefore, we strive to deepen our understanding of how the body regulates its weight and sugar metabolism.

To this end, researchers at the Max Planck Institute for Metabolism Research use a wide variety of methods and technologies. To investigate the molecular basis of obesity and the development of type 2 diabetes, we carry out studies in cell cultures. In order to answer more complex questions, however, we have to look at an entire organism. For example, we cannot study the question of how the brain controls the feeling of satiety and hunger on individual cells, but have to study the entire body. To do this, we use the mouse as a model organism and carry out studies on human volunteers. In the long term, our research will contribute to the development of new molecular therapies for diseases such as diabetes and obesity.

How animal research is legally regulated in Germany and how our animals are kept – answers to these questions and more can be found here.

  1. Why do we need animal studies in basic research?
  2. Laboratory animals and animal welfare
  3. Authorisation of Animal Studies: the Legal Situation in Germany
  4. How are the animals kept?

More information

Portal: Animal Studies of the Max Planck Society

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Declaration of principle on animal research of the Max Planck Society

Animal Experimentation in Research
Information brochure by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)

Understanding Animal Research
This website, of the British group UAR, provides a wealth of information about animal research and the resulting advances in science and medicine.

Why do we need animal studies in basic research?

One of the main aims of basic biological and medical research is to obtain an image as comprehensive as possible of the complex interactions that take place in the human body. This is essential to gaining an understanding of diseases and to the development of corresponding drugs and treatment methods. Although a large part of biomedical basic research involves animal-free testing methods, some questions can only be answered with the help of animal research. Alternative methods, such as computer models and cell cultures, can only reveal part of the overall picture. This is particularly true for studies on the regulation of metabolism by the brain, since hormones from different organs communicate the energy state of the body to the brain. The aim of our investigations is to define exactly which specialized nerve cell types in the brain regulate food intake and sugar metabolism.

Given the extensive biological similarity between humans and animals, laboratory animals offer the best possible alternative when it is not possible to study complex processes and interactions in the body directly on humans. All of the cells and organs, for example the heart, liver, kidneys, nerves and brain, fulfil the same tasks in two-legged and four-legged beings. Many diseases that pose a threat to humans also arise in the same or similar form in animals. Dogs get diabetes, some rats develop high blood pressure and mice and rats suffer from cancer and viral infections. Therefore, many questions can be answered with the help of tests in so-called "animal models". The differences between humans and animals are, of course, taken into account in the design of the tests – for example, in the dosage or way in which drugs are administered.

Moreover, such research often results in the discovery of treatments that can be used on both humans and animals. Almost 90 percent of all drugs used to treat humans and house pets are identical.

Laboratory animals and animal welfare

Research organisations cannot avoid working with animals – those seeking to understand biological correlations must carry out experiments on animals (see section "Why do we need animal studies in baisc research?"). The protection of the laboratory animals is a particular concern for all employees of the Max Planck Society who carry out animal tests. Animal welfare, the best possible holding conditions and the responsible handling of the animals are an ethical obligation for the Max Planck staff. Animal welfare is also in the interests of the scientists, as animal welfare is an essential precondition for obtaining reliable and reproducible scientific results. Each experiment is carefully planned and possible alternatives are considered. Efforts are also made in relation to the care and holding of the laboratory animals. The animals are looked after by experienced vetinarians and qualified keepers.

Max Planck Society scientists make every effort to minimise both the number of animal studies carried out and the stress caused to the animals during the individual experiments. To this end, we apply the 3R principle (reduce, refine and re¬place) in the planning and implementation of the tests: The number of animals used per experiment is reduced to the absolute minimum required (reduction); the implementation of the experiments and holding of the animals are optimised in such a way that the animals suffer as little stress as possible (refinement); if possible, animal experiments are replaced by alternative methods (replacement).

Of all of the activities involving the keeping and use of animals in Germany, animal research is subject to the most rigorous control. All experiments carried out on vertebrates are subject to authorisation, and the regulating authorities check in each individual case whether the experiment is essential or if the desired information can be obtained in a different way. Representatives of the relevant authorities have the right to access test facilities and animal holding areas at all times.

Animal studies and replacement and complementary methods for animal experiments are closely connected. In terms of the level of funding provided for basic research, for a considerable time now, the financial support for replacement and refined methods has been higher than for actual animal experiments.

Authorisation of Animal Studies: the Legal Situation in Germany

In Germany and many other countries, strict controls are in place to ensure that animal experiments are kept to a minimum. The German Animal Welfare Act (Tierschutzgesetz TSchG) – from an international perspective, one of the most stringent laws governing this sector – regulates animal research in Germany. Section 5 of the Act (§§ 7-10 TSchG) provides a precise definition of animal studies, as well as when and under which preconditions it may be carried out. In the case of experiments on mammals, researchers require authorisation from the relevant authority for each individual experiment planned.

The application for the authorisation of an animal study must be submitted in writing to the relevant authority. The detailed application must specify exactly why the research objective cannot be achieved without the use of laboratory animals. The authority is supported by an advisory commission (§ 15 TSchG) in its decisions to grant or reject an application for an animal study. The majority of the members of this commission must have the expert knowledge in the area of veterinary medicine, medicine or science necessary for the assessment of animal experiments. One third of the commission members is selected by the authority from lists proposed by animal welfare organisations.

The Animal Welfare Act also specifies that animal studies may only be carried out by persons who have the necessary training and can provide proof of this training. If an experiment involves pain or significant stress to the animal, normally a sufficient dose of painkiller or anaesthetic must be administered. In this way, the Act ensures that all animal studies are carried out in a way that provides optimum protection for the animal, and subjects it to the minimum possible level of stress.
Animal keeping and the implementation of the experiments are also subject to rigorous controls: the Animal Welfare Act requires that they be monitored by an independent veterinarian. Representatives of the authorising authorities carry out unannounced inspections of research facilities several times per year.

Animal keeping

Most of the animals used in our experiments are bred at the institute. The remaining portion comes from other research institutes or from specialized breeders who are monitored by the relevant authorities. The housing of animals in our animal facilities is based on the very latest scientific knowledge in the field of laboratory animal science. Highly trained and experienced animal keepers, together with veterinarians and biologists, ensure that the animals are held under conditions that comply with animal welfare regulations and meet the varying needs of the different animal species. To keep our high standards in animal keeping we have our own trainee program for animal caretakers. The accommodation provided for the animals reflects their species-specific requirements. For example, mice are held in family or sibling groups insofar as there are no medical or experimental reasons opposing this. Cages provide opportunities for withdrawal and activity; particular attention is paid to hygiene as the basic way of ensuring that the animals remain healthy.

Meticulous animal keeping ultimately serves the interests of science: useful scientific results can only be obtained from animal experiments that are carried out with healthy animals kept in stress-free and species-appropriate conditions.

The breeding and keeping of the animals as well as the experiments are monitored by the institute's animal welfare officer, and by the relevant authorities. To ensure that the animals suffer as little stress as possible, the scientists plan the experiments in cooperation with the institutes’ animal laboratory manager and animal welfare officer.

Mice keeping

Mice held in our animal facility live in groups. The young are separated from their mothers after weaning and are kept in groups of the same sex. Only mature males that have mated with a female often have to be isolated, as they then become so dominant that they can no longer be kept in a group.

Mice are kept in see-through plastic cages with an area of at least 370 square centimetres. Three to six mice live in each cage, depending on their weight. The cages are 14 centimetres high and are covered by a grating, which the animals use for climbing. The cages contain a feed trough and water bottle.

Each cage contains litter of wood shavings or chips. Small hiding places made of red, transparent plastic – known as mouse houses − serve as retreats. Paper strips, excelsior or hemp provide material for nest building and activity. A standardized complete feed in pellet form that provides all the required nutrients and water are freely available.

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