Keystone Veterinary Services was built and established by Dr. Gerhard Hartung. After over thirty years of service to the community, Dr. Hartung retired in January 2023 and sold the practice to Dr. Petra Collyer.

Petra Collyer DVM PhD CVA VSMT 

is a German-American veterinarian with extensive experience in companion animal medicine. She attended the Free University of Berlin, Germany, and the University of Glasgow, Scotland, and earned her DVM in 1999. After graduation, Dr. Collyer started practicing veterinary medicine in a mixed animal practice in Scotland, and a few years later accepted a position at the University of Berne, Switzerland, to pursue her PhD in equine medicine. After completing her dissertation and working in Alsace, France and Switzerland with large and small animals, Dr. Collyer moved to the US in 2004. Since then, she has been working at an equine referral center, at universities, and at small animal practices in and around Pittsburgh.  

Dr. Collyer is continuously pursuing education to expand her toolbox. Dr. Collyer is Fear Free certified, and earned her certification in small animal and equine acupuncture (CVA) and advanced acupuncture through the CHI University in Reddick, FL, a global leader in Traditional Chinese Veterinary Medicine (TCVM). Postgraduate training in integrative palliative care, hospice and end of life care with CHI University further supported Dr. Collyer's passion to care especially for older pets with chronic health problems. Dr. Collyer is certified in small animal and equine veterinary spinal manipulative therapy through the Veterinary Chiropractic Learning Center in Ontario, Canada, which is accredited by the AVCA (American Veterinary Chiropractic Association). Dr. Collyer delivers integrative care and uses a combination of medical approaches to provide the best care, quality of life and happiness for her patients.

Dr. Collyer and her family share their life with Maestro (American Foxhound), Bowie (Paws across Pittsburgh alumna), Friesian Sport Horses and a former race horse on their farm in Shelocta.