This is from the North Carolina Board of Massage and Bodywork Therapy website FAQ:
17. Do practitioners who massage horses or other animals need to get licensed by this Board?
No -- as long as their work is limited to animals. The legal definition of massage and bodywork therapy in the Practice Act refers to โsystems of activity applied to the human body for therapeutic, educational or relaxation purposes.โ
The board's website is: http://www.bmbt.org . You can find the law in its entirety there, among other things.
Hope that helps!
Emily