About Our Training and Veterinary Practice

Welcome to Mertens Mammals! We are the home of behavioral health for horses and other animals, created by equine and small animal veterinarian, Katharine Mertens. We are the only equine practice in the Pacific NW to combine veterinary expertise with positive reinforcement training for horses and dogs. We are based in Boring, OR and serve horses in Clackamas County and the greater Portland area.

Mertens Mammals aims to help all horse and dog owners improve the mental and emotional health of their animals, with a special emphasis on overcoming problem behaviors as may be encountered during veterinary procedures, handling and day to day life.

We offer clicker training instruction for you and/or your 4-legged friends–together or separately–for basic handling, and for solving behavior problems. Our methods are rooted in animal behavior science. If you have a challenging behavior dilemma, please don’t hesitate to call or text (503) 663-6400. We look forward to helping you find science-based, ethical, and effective solutions.

We know that with behavior science–not myths–miraculous results are truly possible.

Veterinarian Kath Mertens standing with horse.

Kath Mertens, DVM – Veterinarian; Practice Owner

Dr. Mertens earned her DVM from the Purdue University School of Veterinary Medicine in 2000, and also holds a degree in English from Harvard.

Kath’s interest in horses has taken her across the ocean and the continent, working at internships in Ireland and France and hitting the trails in Long Island, NY; Wyoming, Montana, and now Oregon. She is a dedicated student of the horse and enjoys studying equines from both a medical and horsemanship perspective. Her primary riding interests are back-country trail riding, three day eventing, and dressage.

Kath enjoys leisure time with her son and their black Labrador, Makai, and a recently adopted cat. She also enjoys training her 10 yro OTTB mare, Luna; reading, writing, long-distance running, and yoga.

Sammi Jones, R+ trainer

Sammi Jones joined Mertens Mammals as a trainer in the Winter of 2022. She has had a lifelong passion for animals, especially horses. Learning about positive reinforcement training in 2019, Sammi was instantly hooked by the ability to train animals with empathy and without force. Sammi has used positive reinforcement to train horses—from Percheron Draft to American Miniature—as well as dogs, donkeys, llamas, alpacas, and house cats.

Outside of training, Sammi spends her down time playing sports (ultimate frisbee is a favorite), reading, and enjoying friends and family. Sammi lives in Gresham, OR with her husband and two cats.

Positive reinforcement training allows the animal to have choice and control. The relationship this training builds between animal and human is truly special. –Sammi Jones