John Calhoun graduated from Texas A&M University in 1990. He has been with North Carrollton Veterinary Hospital since 1991 and is the current owner. His special interests include endocrinology and cardiology. In his spare time, he enjoys Martial Arts. Dr. Calhoun is a member of the Dallas County Veterinary Medical Association (DCVMA), Texas Veterinary Medical Association, and Texas Association of Veterinary Practitioners. He is presently serving on the board of directors for the DCVMA and the North Texas Emergency Pet Clinic [citation].