Dr. Johnson received the title of veterinarian at Ohio State University, then he spent three years in a small animal clinic in New York, and graduated MA and residency at the University of Illinois. He is a certified member of the American College of Veterinary Medicine. The theme of research thesis of dr Johnson was a feline asthma. After residency, Dr. Johnson held an internship in the field of oncology and radiology at Colorado State University. He received a grant funded by the National Institute of Health Heart, Lung and Blood on the study of the effects of physical activity on vascular function in the lungs, and in 2000 received a PhD in Physiology from the University of Missouri. Dr. Johnson is the editor of the chapter on respiratory diseases in the publication of "5 Minute Veterinary Consult and Current Veterinary Therapy XV," and recently wrote a textbook in the field only to respiratory diseases "Clinical Canine and Feline Respiratory Medicine". He is a member of the Veterinary and Comparative Respiratory Society.
Dr. Johnson's research interests include clinical respiratory disease of dogs and cats, and interactions heart-respiratory system. In December 2000, Dr. Johnson started working at the Faculty of Veterinary Medicine at the University of California, where he is currently a professor at the Department of Internal Medicine and Epidemiology. He is leading classes in the field of respiratory diseases and clinical medicine for veterinary students and consultations in the field of endoscopy and physiology of the respiratory system for residents.