Euthanasia and Necropsy

This chapter is designed to give a general overview of euthanasia and necropsy techniques that may be used for laboratory rabbits, guinea pigs, rats, mice, and other rodents. The euthanasia techniques described are those approved by the American Veterinary Medical Association. "Euthanasia" is a noun from Greek origins: eu (meaning "good") and thanatos (meaning "death"). In other words, euthanasia is death that is induced with minimal pain and distress. Euthanasia of an animal should be performed in a humane manner. The techniques used should cause rapid unconsciousness, respiratory or cardiac arrest, and loss of brain function. Euthanasia can be distressing to personnel, especially when performed repeatedly and to reduce human distress during the euthanasia process, personnel are provided with counseling, education, and training. Pain is not experienced if the cerebral cortex and subcortical structures are nonfunctional. These structures can be made nonfunctional by induction of hypoxia, the use of various anesthetics and analgesics, or other physical means. Approved methods for euthanasia are typically chemical or physical, and the optimal choice in a particular situation varies based on age, use, and species differences. The method of euthanasia selected should be based on compatibility with postmortem data collection needs. Agents used for euthanasia may produce changes in research data and should therefore be carefully selected. Some physical methods of euthanasia may pose safety issues for personnel; for example, the guillotine, if improperly used, can cause injury to the user, and human exposure to inhalant anesthetics is associated with liver and kidney damage, cancer, and complications during pregnancy.