Meet Our Instructors
Dr. Amy Johnson
Dr. Johnson is the Marilyn M. Simpson Professor of Equine Medicine, section chief of internal medicine and ophthalmology, and professor of large animal medicine and neurology at the University of Pennsylvania’s New Bolton Center. Her clinical caseload consists predominantly of horses with neurologic problems, including spinal cord compression, neurodegenerative disease, and infectious diseases. She also provides consultations for farm animals with neurologic disease. Her research efforts focus on improving our ability to diagnose the cause of neurologic disease in horses.
After earning her veterinary degree from Cornell University in 2003, Dr. Johnson completed an internship at B.W. Furlong & Associates in Oldwick, N.J., followed by a large animal internal medicine residency at Cornell and neurology residency at Penn Vet. She was the first American veterinarian to obtain board certification in both large animal internal medicine and neurology. She joined the Penn Vet faculty in 2011.
Dr. Sarah Colmer
Dr. Colmer is a large animal internist and neurology fellow at the University of Pennsylvania’s New Bolton Center. She has research interests in neurologic conditions of the horse, particularly degenerative diseases, as well as endocrinology.
After receiving her veterinary degree from the University of Pennsylvania in 2017, Dr. Colmer completed a rotating internship at Mid-Atlantic Equine Medical Center in Ringoes, N.J., followed by a rotating internship and large animal internal medicine residency at New Bolton Center, achieving board certification in 2022. She received the 2024 William B. Boucher Award for Outstanding Teaching as voted on by the graduating class. Dr. Colmer is currently in the final year of a neurology residency program, aiming for her second ACVIM board certification in 2026.
Dr. Yvette Nout-Lomas
Dr. Nout-Lomas is an associate professor of equine internal medicine at Colorado State University College of Veterinary Medicine & Biomedical Sciences. Her clinical interests include evaluation and treatment of horses with neurologic and behavior disorders and critically ill foals and adult horses. Her research goal is to improve diagnostic capabilities and treatment options for horses with neurologic disease. In particular, her research focuses on gait assessment in horses, spinal cord injury, and comparative neuroscience.
Dr. Nout-Lomas received her veterinary degree in 1999 from Utrecht University in The Netherlands. After completing a rotating internship at the Marion duPont Scott Equine Medical Center in Leesburg, Va., she completed residencies in Equine Internal Medicine and Equine Emergency and Critical Care at The Ohio State University, becoming boarded in both specialties. She earned a PhD in Neuroscience in the College of Medicine of The Ohio State University and then completed postdoctoral work in comparative neuroscience at the University of California in San Francisco. She joined the CSU faculty in 2014.
Dr. Amy Polkes
Dr. Polkes is founding owner of Equine IMED (Internal Medicine and Diagnostic Services), which provides mobile internal medicine service for cases that would otherwise require transport to a referral facility. She established the practice in 2003 servicing Maryland and Virginia and later expanded to offer monthly service in New York, Connecticut and Pennsylvania.
Dr. Polkes received her veterinary degree from Purdue University. Following several years in private practice, she completed a large animal internal medicine residency at the University of Florida, becoming board certified after completing the program in 2002. In addition to Equine IMED, Dr. Polkes is the equine internal medicine specialist for Antech Diagnostics, helping facilitate expansion of equine diagnostic testing within Antech Diagnostics.
Dr. Elizabeth Acutt
Dr. Acutt is an assistant professor of clinical large animal diagnostic imaging at the University of Pennsylvania’s New Bolton Center, where her clinical and research interests focus on comparative imaging in the equine athlete.
After receiving her veterinary degree in 2015 from the University of Bristol, UK, Dr. Acutt traveled to the University of California, Davis to undergo additional training in equine orthopedics and sports medicine. She was the first person to complete a residency specifically in equine diagnostic imaging, based at Colorado State University, and became a diplomate of the American College of Veterinary Radiologists (EDI) in 2022. She joined the faculty at Penn Vet in 2023.
Dr. Kathryn Bills
Dr. Bills is an associate professor of clinical large animal diagnostic imaging at the University of Pennsylvania’s New Bolton Center, having joined the faculty in 2016. Her work focuses on the clinical applications of advanced imaging systems, including CT, MRI, and novel standing imaging systems, including PET and a robotics-controlled cone beam CT.
Dr. Bills obtained her VMD from the University of Pennsylvania in 2012 after graduating from Tufts University with a degree in biochemistry. Following a rotating internship in equine medicine, surgery, and critical care at the New Bolton Center, Dr. Bills completed a diagnostic imaging residency at Tufts University’s Cummings School of Veterinary Medicine. She became board-certified in diagnostic imaging by the American College of Veterinary Radiology in 2016 and received additional board certification in equine diagnostic imaging (DACVR-EDI) in 2022.
Dr. Kara Brown
Dr. Brown is an assistant professor of equine sports medicine and rehabilitation at the University of Pennsylvania’s New Bolton Center, from which she received her veterinary degree in 2014. After graduation, she completed an equine internship at Woodside Equine Clinic, followed by a large animal internship, a clinical fellowship in large animal cardiology and ultrasound, and a residency training program in equine sports medicine and rehabilitation at New Bolton Center.
Dr. Brown is a boarded diplomate of the American College of Veterinary Sports Medicine and Rehabilitation and has a strong clinical and research interest in poor performance in the equine athlete, axial skeletal pain and regenerative medicine.
Upcoming Events
69th AAEP Annual Convention
All sessions are now available for purchase. View On Demand Here
Virtual Wednesday Round Table: Acupuncture in Sport Horses
This content is an exclusive benefit for AAEP members. If you’re a…
Virtual Wednesday Round Table: Stress & Distress in Equine Medicine: A Path Towards Wellbeing
This content is an exclusive benefit for AAEP members. If you’re a…
