No need for pain

In some areas, the use of animals for research on various issues is still irreplaceable. As long as this is the case, however, it must be ensured in any case that "pain, suffering, distress or lasting harm is eliminated or reduced to a minimum". Thus, there is a legal requirement (RL 2010/63/EU) to maintain the physical and psychological health of laboratory animals.

Also the principle of refinement, one of the 3Rs in animal experimentation, is to guarantee maximum animal welfare, which can be achieved by keeping the animals as species-appropriate as possible, animal-friendly handling and other measures that contribute to the well-being of the animals. In some experiments, animals are subjected to painful procedures. Appropriate analgesia and, in some cases, anesthesia, must be provided to prevent the associated suffering. The recognition of pain and the treatment of this pain is a central issue in animal experimentation and requires profound knowledge and experience. Since animals are not capable of verbally communicating their pain, researchers rely on recording clinical symptoms or changes in species-specific behavior to draw conclusions about painfulness and thus determine whether analgesia is needed. A prerequisite for this is, of course, knowledge of the normal condition of the species. Abnormal movements, altered facial expression or vocalization in the ultrasonic range would be examples of typical behavior patterns that signal pain in rodents. Digging, nest building, or fur grooming would be indications of rodent well-being. Score sheets are used to assist in recording all symptoms and behavior patterns. These protocols are adapted to the species in question and the planned experiment. They have a scoring system that determines whether analgesia or other interventions are needed. For more information, see our article on score sheets. Adequate pain management requires pharmacological knowledge and knowledge of the species used. Thus, it is necessary to check which pharmaceuticals can be used for the species or even the strain in question. In addition, it must be considered whether the analgesic is suitable for the particular experiment or could have an influence on results. The efficacy of analgesia must likewise always be checked, for example with the aid of score sheets. In addition to pharmacological pain management, there are other methods to reduce pain and stress. For example, factors such as handling, the husbandry and environment of the animals, but also the surgical methods used, play a major role. Numerous sources on the internet can be used to create an analgesia protocol tailored to the model. It is also advisable to consult experts, such as veterinarians from the laboratory animal field or other experienced persons, in order to ensure appropriate pain management.

Further information on analgesia and dosage tables can be found in the following sources, among others:

• GV- Solas- Pain management for laboratory animals
• IACUC - Guidelines Analgesia
• PennState University - Pain Recognition and Analgesia in Laboratory Animals
• Norecopa - Analgesia
• Flecknell, P. A., & Thomas, A. A. (2015). Comparative anesthesia and analgesia of laboratory animals. Veterinary anesthesia and analgesia: the fifth edition of Lumb and Jones, 754-763.

Sources:
RL 2010/63/EU https://www.gv-solas.de/wp-content/uploads/2020/09/Schmerztherapie-bei-Versuchstieren_2020.pdf (Zugriff 29.08.2023)
https://animal.research.uiowa.edu/iacuc-guidelines-analgesia (Zugriff 29.08.2023)