What is the benefit of using physical methods over non-physical methods for euthanasia?

The use of physical methods for euthanasia offers the benefit of ensuring rapid loss of consciousness, which is a critical aspect of a humane euthanasia process. These methods, when performed correctly, lead to an immediate and irreversible state where the animal is no longer aware or capable of experiencing pain. This rapid onset is essential for minimizing distress at the time of euthanasia, aligning with ethical guidelines that prioritize the welfare of the animal.

In contrast to this, non-physical methods may not lead to such immediate effects, potentially prolonging the animal's distress, which is not desired in a humane euthanasia procedure. Therefore, the correct choice emphasizes the importance of swift and effective loss of consciousness, highlighting the humane aspect in the practice of euthanasia within the scope of IACUC considerations.