Which of the following is NOT a valid reason for euthanasia in a research context?

Euthanasia in a research setting is governed by ethical guidelines and considerations aimed at minimizing animal suffering while ensuring scientific integrity. One of the core principles in animal research is the humane treatment of subjects.

In this context, choosing to euthanize an animal that is still capable of living a healthy life contradicts the ethical obligation to alleviate unnecessary suffering. Euthanasia should only be carried out when an animal is experiencing pain and suffering that cannot be relieved, or when it is necessary to prevent further suffering, such as in cases of severe illness or injury.

When evaluating the other options, euthanasia to alleviate pain and suffering is a widely accepted reason, as is conducting euthanasia for scientific purposes following the completion of a study—provided that it adheres to ethical standards. Additionally, proper disposal of animals post-experiment is also justified to maintain hygiene and prevent distress for researchers and other animals. However, euthanizing healthy animals without a justifiable reason reflects a disregard for their welfare and the principles that guide responsible animal research.