Walker Valley Veterinary - Our Doctors

  • Dr.
    Christine Barnhorst

    Dr. Christine Barnhorst received a BS in Biology from the University of Notre Dame in 1991 and a DVM from Purdue University in 1995. After graduating from Veterinary School, Dr. Barnhorst served as a Captain in the United States Army for 4 years where she trained enlisted soldiers, performed public health duties and cared for military working dogs and pets of military families.

    She and her husband, Brad, moved into an old farmhouse in NY and began raising two beautiful girls. They currently have 3 dogs and 2 cats.

    She has been practicing as a small animal veterinarian in New Jersey and New York since 1999. At the end of 2019, Dr. Barnhorst enthusiastically took over the responsibilities of managing Walker Valley Veterinary Hospital. Dr. Barnhorst enjoys practicing high-quality veterinary medicine and surgery and has a special interest in dentistry and nutrition.

  • Dr.
    Stephanie Chlebowski

    Dr. Stephanie Chlebowski grew up with a love for animals. After receiving a B.S. in Small Animal Science from Delaware Valley University, Dr. Stephanie then attended the University of Missouri and graduated with her veterinary degree in 2016. Following graduation, she practiced for 7 years in Sussex County, NJ where she focused on developing relationships with clients and caring for their pets through all life stages. 

    Dr. Stephanie currently resides in Orange County with her husband, Tim, their two rough collies, Fleetwood and Whellie, and a betta fish named Paul Hollywood. Dr. Stephanie enjoys playing the guitar, gluten free baking, gardening, and hiking. Her professional interests include preventative care, exotic animal medicine, and dentistry. 

  • Dr.
    Barbara MacMullen

    Dr. MacMullen is originally from Saugerties.  After earning her bachelor's degree from Cornell University, she lived in Tuscany for 7 years and attended the Veterinary College at the University of Pisa.  She finished her veterinary degree at Aranela University in Manila, Philippines.  She did post-graduate clinical studies at the University of Missouri College of Veterinary Medicine in Columbia, and at the Animal Medical Center in NYC.

    Dr. MacMullen started her career at a local emergency facility, and Hopewell Animal and Bird Hospital.

    She has worked with local animal shelters including the UCSPA and PCSPCA. In 1999 she opened her own house-call practice called Pet's Reward. Currently she splits her time between her house-call practice, the UCSPCA and Walker Valley Vet where she sees appointments two Saturdays a month.

    Dr. MacMullen lives in Kingston with her partner of over 20 years, Tim Dunton. Tim is a blue stone craftsman specializing in landscape designs. They have a Basset hound named Grace, 2 cats and a ball python.

  • Dr.
    Jean-Paul Petrie
    DVM, DACVIM Veterinary Cardiologist

    Dr. Petrie is a mobile board certified veterinary cardiologist that is able to examine, perform echocardiograms, and manage our heart patients at Walker Valley Veterinary Hospital. Dr. Petrie completed his DVM degree at the Ontario Veterinary College, University of Guelph, Ontario, Canada in 1994. Following veterinary school, he completed his internship at Michigan Veterinary Specialists, Southfield, Michigan. Prior to completing his residency he completed a post-doctoral fellowship in cardiac physiology and interventional cardiology at the Robarts Research Institute, University Hospital, London, Ontario, Canada. Dr. Petrie then traveled to New York to complete his residency in veterinary cardiology at the Animal Medical Center in New York in 1996. He was a staff cardiologist in the department of medicine at the Animal Medical Center where he was employed for almost 11 years. He is board certified by the American College of Veterinary Internal medicine in Cardiology since 1999. Jean-Paul has specific interest in echocardiography and feline cardiomyopathies. He continues to lecture both nationally and internationally. Dr. Petrie continues to be actively involved in clinical research projects and has published several articles and book chapters while continuing to be active with his career.

Contact Us

We look forward to hearing from you


Find us on the map

Office Hours

Our Regular Schedule

Walker Valley Office


9:00 am-6:00 pm


9:00 am-5:00 pm


9:00 am-6:00 pm


9:00 am-7:00 pm


9:00 am-5:00 pm


9:00 am-1:00 pm