Evaluation of a mixture of medetomidine, alfaxalone and butorphanol as an alternative drug for euthanasia in mice.

Euthanasia agents should induce a rapid and painless loss of consciousness, followed by cardiopulmonary arrest and subsequent brain death. Injectable drugs such as pentobarbital sodium are commonly used for laboratory rodents due to their quick and smooth action. However, the discontinuation of pharmaceutical-grade pentobarbital sodium and secobarbital sodium in Japan, along with a global shortage of pentobarbital in late 2020, has increased the demand for new injectable euthanasia drugs.