The most commonly used experimental animals according to the 2022 experimental animal report were chickens, followed by sheep, mice, rats, and frogs.
With chickens, the University of Hohenheim investigates the make-up of ideal feed and evaluates new feed sources as alternatives to imported grain (environmental protection and lower use of resources), as well as the basics of interactions between the animal and microbiome in the digestive tract. The question of how to prevent feather pecking (animal welfare) is also one of the research questions that were addressed.
With mice, the university looks at human nutrition (especially for disease prevention / health), immune reactions, and other biological issues.
Many other studies on farm animals do not require the use of experimental animals because data from farms or slaughterhouses is used.
Drawing blood from lambs to promote the breeding of robust pasture-fed lambs or fitting EEG sensors to pigs to evaluate new, non-invasive methods: Experiments like these are not very stressful for the animals. In the animal experiments registered in 2022, around 85% of the animals were used in experiments like these.
Experiments with a mid-level severity classification are e.g. those in which wild dormice are caught and marked.
In 2.6% of the experimental animals reported in 2022, the animal did not recover consciousness, e.g. after an experiment was carried out under anesthesia. A further 8.8% of laboratory animals were killed in order to remove organs or tissue such as muscles, nerves or digestive organs for research.
How stressful an experiment is for an animal is defined in EU Directive 2010/63/EU, Annex VIII “Severity Classification of Procedures,” where the criteria are illustrated with practical examples.
In the animal experiments registered in 2022, around 95% of the animals were used in research.
Around 1.76% of the animals were used for experiments in student education and training. These include two compulsory courses in the Biology and Agricultural Biology Bachelor’s degree programs. A further 1.6% were used in professional education and training.
The category “animal experiments for other purposes” is for e.g. experimental animals that are used to maintain specially bred colonies. These are e.g. mice that are genetically engineered so that they can serve as models for many human illnesses to research causes of diseases and treatments.