S.D. Codified Laws § 40-1-20

Except as specifically provided for in this chapter, no person may intentionally administer poison to any animal that belongs to another, nor intentionally expose any poisonous substance so that it may be taken by an animal which belongs to another. A violation of this section is a Class 1 misdemeanor. This section may not be construed to prevent euthanasia by a licensed veterinarian with proper authority from the animal's owner nor may it prevent acts of euthanasia authorized by this chapter. This section may not be construed to prevent animal control activities conducted by municipalities or counties.