It shall be the duty of the director of the animal shelter, and he is hereby so authorized
and empowered, to issue and sign a death warrant and order euthanasia for any animal
lawfully taken into the custody of the animal shelter department which in the opinion
of the director is by reason of old age unfit for further use, or which is adjudged
by a written request of a licensed veterinarian to be infected with any dangerous
or communicable disease other than rabies, or which is in an incurably crippled condition,
or is afflicted with intractable pain or incurable disease.