Number of animals used for scientific purposes at the MDC
At the MDC, researchers use mice, rats, and zebrafish in animal experiments. In addition, there is a small colony of naked mole rats at the MDC, which also serve as models for research. In the statistics, these are listed under "Other rodents". The rabbits, guinea pigs, and golden hamsters live at the MDC for the training of animal caretakers. Rabbits are also kept for the production of antibodies.
At the MDC, genetically modified mice serve as models for Alzheimer’s disease or for tumor development. Rats are mainly used for cardiovascular research, and zebrafish as a model for common developmental disorders of the heart.
The MDC also investigates special biological abilities that animals possess but humans lack, in an effort to understand and learn from them. People who suffer a stroke, for example, usually suffer permanent damage due to the associated oxygen deprivation. Naked mole rats, however, can go for a long time without oxygen and suffer no damage at all. Zebrafish hearts, meanwhile, are able to repair themselves – which would be helpful for people suffering from heart disease.
Of the approximately 1.3 million and registered by the , almost four percent were used for studies at the MDC (52,078 animals). These were mainly mice (49,196) and rats (1,917). The MDC also conducts animal research using zebrafish and naked mole rats. All animals that have been used in a study or been born as the result of breeding efforts at the MDC are reported to the BMEL each year.
Over the course of one year, about 300 animal studies are conducted in parallel, typically involving about one hundred animals per study.
The number of animals required for a single study is always determined by the research question and scientific criteria. The number of animals must be high enough to ensure the likelihood of a statistically relevant result. This is the only way to make sure the study has any predictive power. While one study may manage with five animals, another may require around one hundred. Because of the breeding, keeping and approval processes involved, animal studies require a lot of money and time. They are therefore always the last, never the first, choice for MDC researchers to find answers to their research questions.
Type of experiments according to severity categories
In addition to the number of experimental animals and information on the animal species used, the annual report to the LAGeSo, which is the authority responsible for the MDC, also includes information on the severity of the animal experiments. The categories of severity and how the experiments must be classified into these categories are laid down in Directive 2010/63/EU of the European Parliament and of the Council of 22 September 2010 on the protection of animals used for scientific purposes. We have listed the exact definitions here:
Procedures which are performed entirely under general anaesthesia from which the animal shall not recover consciousness.
Procedures on animals as a result of which the animals are likely to experience short-term mild pain, suffering or distress, as well as procedures with no significant impairment of the well-being or general condition of the animals.
Procedures on animals as a result of which the animals are likely to experience short-term moderate pain, suffering or distress, or long-lasting mild pain, suffering or distress as well as procedures that are likely to cause moderate impairment of the well-being or general condition of the animals.
Procedures on animals as a result of which the animals are likely to experience severe pain, suffering or distress, or long-lasting moderate pain, suffering or distress as well as procedures, that are likely to cause severe impairment of the well-being or general condition of the animals.
What was the level of severity of the animal experiments at the MDC in 2019 and how many animals were used?
Most of the animal experiments at the MDC in 2019, only caused a minor distress to the animals (category: mild). Another large proportion of the animals reported by the MDC were killed for scientific purposes, for example to examine cell or tissue samples. They are included in the statistics under "non-recovery". This category also includes experiments conducted under general anesthesia, where the animal is killed under anesthesia.
A very small number of animals are used in experiments that involve severe stress. Here, however, our scientists are obliged to reduce the stress - if at all possible - by using painkillers. They must also weigh up the burden against the expected medical and scientific benefits. In principle, the 3-R rule (reduce, refine, replace) applies: This means that researchers must keep the number of experimental animals as low as possible, minimise pain and suffering and use alternative methods whenever possible.