Equine Staff

Equine Veterinarians

Martin G. Crabo, DVM
Co-Owner of Chaparral Veterinary Medical Center
Equine Sports Medicine
Equine General Practice

Dr. Crabo joined Chaparral Veterinary Medical Center in 1991. He graduated from the University of Minnesota, College of Veterinary Medicine in 1990 and subsequently completed an internship in Large Animal Medicine & Surgery at Washington State University. Dr. Crabo is married to Barbara, an Eventing Trainer having completed the prestigious Rolex Kentucky CCI****. Together they have a daughter named Jordan (also an avid Eventer), 14 horses, 3 dogs, 3 cats and a Cockatoo on their "ranch," Four Peaks Farm. When the family gets a rare chance to get away, the Crabos enjoy horse shows, snow skiing, and the ocean together. Professionally, Dr. Crabo's interests include equine sports medicine, lameness, and imaging as well general equine practice. He strives for an in-depth knowledge of equine ultrasound and anatomy through his membership in ISELP, the International Society of Equine Locomotor Pathology.
C. Renee Andrea, DVM, DACVS
Diplomate of the American College of Veterinary Surgeons (Large Animal)
Co-Owner of Chaparral Veterinary Medical Center
Equine Surgeon
Equine Sports Medicine
Dr. Andrea was born and raised in the state of Washington where she held her first job cleaning kennels at the Gig Harbor Veterinary Hospital. She obtained her Associates Degree in Animal Health Technology and worked her way through college as a Certified Veterinary Technician. She then attended Washington State University where she graduated with a B.S. in Animal Science in 1990, and her DVM, with honors, in 1994. Dr. Andrea came to Arizona to complete an internship at Arizona Equine and thereafter, completed a residency in equine surgery at the University of California, Davis. She earned her Diplomate status as a Board Certified Equine Surgeon in 1999. Dr. Andrea joined Chaparral as an equine surgeon in 2001 and became a partner in the practice in 2003. She was grateful to help build the referral and surgical portion of the practice and the transition into Chaparral Veterinary Medical Center in 2008 was a dream come true. She has enjoyed growing with the practice over the years and continues to be a huge part of the Chaparral team.
Dr. Andrea has published research in equine orthopedics, as well as soft tissue reconstructive surgery. She specializes in all areas of lameness, sports medicine, and surgical conditions of the horse. Training in the southwest solidified her love of the acute abdomen (surgical colic), but her true passion is orthopedic and reconstructive surgery. Dr. Andrea brings a unique perspective to diagnosing and treating conditions of the equine athlete, being a barrel racer herself and having years of experience working on horses from all disciplines with performance-limiting lameness issues. She strives to provide the most cutting edge treatment modalities to her patients, staying current with advances in regenerative medicine and combining these treatments with surgical therapy when needed.
Dr. Andrea and her family (husband Mike Freeland, and sons Canon and Shea) currently have 9 horses that complete their rodeo team. When not making a run herself, she is keeping the rope horses working.
Rachel Liepman, DVM, MS, DACVIM
Diplomate of the American College of Veterinary Internal Medicine (Large Animal)
​​​​​​​Equine Internal Medicine
​​​​​​​Neonatal Foal Care

Dr. Liepman joins Chaparral from the Midwest, hailing from Michigan. A Wolverine at heart (her alma mater), Dr. Liepman graduated in 2011 from Michigan State University, College of Veterinary Medicine with honors and a Doctorate of Veterinary Medicine. She then completed an internship in equine sports medicine, surgery and internal medicine at BW Furlong and Associates in New Jersey. Thereafter, she accepted a position at The Ohio State University, College of Veterinary Medicine for further training as an equine internal medicine specialist. She became board certified in equine internal medicine and dually received a master of science degree in comparative veterinary medicine from The Ohio State University, studying the effects of intravenous antibiotics on the gastrointestinal health of the horse. Dr. Liepman has published in several different areas in equine medicine including topics in neonatology and gastrointestinal health.
Dr. Liepman especially enjoys equine neonatal care, challenging cases and working up critical emergencies. She spends her free time exploring and enjoying the outdoors with her husband Daniel, her son, Quillen, and their dog, Penelope (blue heeler).
Wade Walker, DVM, DACVS
Diplomate of the American College of Veterinary Surgeons (Large Animal)
​​​​​​​Equine Surgeon
Equine Sports Medicine ​​​​​​​

Dr. Walker is a southern California native and comes from a long lineage of veterinarians. He attended Colorado State University for both his undergraduate and veterinary degrees, where he graduated with honors. During this time Dr. Walker was on staff at the Equine Orthopaedic Research Center and was involved in numerous studies investigating the progression and prevention of equine osteoarthritis using different medical therapeutics and surgical interventions. Following completion of veterinary school, he completed an internship at Arizona Equine Medical and Surgical Centre in Gilbert, Arizona. He accepted a position at Cornell University for a three-year Large Animal Surgical Residency. Dr. Walker worked as an Associate Surgeon at San Luis Rey Equine Hospital prior to joining the team at Chaparral Veterinary Medical Center. Currently, Dr. Walker is a board certified equine surgeon with a special interest in sports medicine. Dr. Walker has published several scientific manuscripts in veterinary orthopedics, upper respiratory surgery, traumatology, and colic and presented his research nationally at several conferences. A list of selected publications can be accessed at the following link (https://www.researchgate.net/profile/Wade_Walker/contributions). His clinical interests include orthopedic, upper respiratory, and oncologic surgery, as well as regenerative and sports medicine. In his spare time, Dr. Walker enjoys outdoor sports with his family and pets.
Christine Moyer, DVM, MS
Equine Surgery and Critical Care interest
Dr. Moyer grew up in Kansas showing hunter/jumper horses, and continued to ride on the Kansas State University NCAA Equestrian Team. She completed her undergraduate degree and veterinary school at Kansas State University, graduating summa cum laude in 2013. Dr. Moyer completed her internship at Rood and Riddle Equine Hospital in Lexington, Kentucky focusing in surgery, internal medicine, and anesthesia. She then completed a second internship in internal medicine at Marion duPont Scott Equine Medical Center in Leesburg, Virginia. She stayed at Marion duPont Scott EMC for her surgical residency until its completion in the summer of 2018. Concurrent with her surgery specialty training, she completed a master's degree focused in equine wound healing. Dr. Moyer has been a part of the team at Chaparral Veterinary Medical Center since July of 2018 and is eager to be a part of the Arizona community. Her clinical interests include a wide variety of emergency, critical care and surgical conditions, with a special interest in critical emergencies and triage care. She also has an interest in equine sinus pathologies and lameness. In her spare time, Dr. Moyer enjoys spending time with her husband, Chance, and German Shepherd, Docker.
Karin Thomasson, DVM
Equine General Practice

Dr. Karin Thomasson was raised on a farm in the great state of Minnesota, where her love for horses and the outdoors began. She waited seven long years to get her first horse and then spent much of her time growing up horseback—training, trail riding, showing, and roping. Dr. Thomasson attended North Dakota State University as an undergraduate, majoring in Animal & Range Science and Equine Studies. To gain additional experience, she worked as an intern at Peterson & Smith’s Equine Reproduction Center in Ocala, Florida, which clinched her desire to pursue equine veterinary medicine. Dr. Thomasson then attended Kansas State University for veterinary school. Go Wildcats! Upon graduation she moved to Glenwood Springs, Colorado completing an equine veterinary internship at Glenwood Veterinary Clinic. She joined the team at Chaparral Veterinary Medical Center in 2015 as an Associate Veterinarian. She enjoys all aspects of equine practice, especially, dentistry and sports medicine. In 2017, Dr. Thomasson pursued a rigorous training program in animal acupuncture and is excited to now offer acupuncture services for horses and small animals. In her free time, Dr. Thomasson enjoys horseback riding and training, hiking, traveling, and anything outdoors.

Anastasia Keyser, DVM
Equine General Practice

Dr. Anastasia Keyser joins Chaparral from Texas. Although she did not get the opportunity to grow up on a ranch, her family always had horses. She was riding before she could walk and continues to maintain that passion for horses. Dr. Keyser initially received a BA in business administration majoring in business management. Her decision to pursue veterinary medicine followed a few years later after realizing that she wanted to do even more to help horses besides training them and running a 501(c)3 horse rescue. She attended Texas A&M University’s College of Veterinary Medicine and Biomedical Sciences. During her time in College Station, she was employed in the large animal ICU at Texas A&M Veterinary Medical Teaching Hospital. After veterinary school, she completed an internship at Reata Equine Hospital in Weatherford, TX. Dr. Keyser is an equine general practitioner who provides ambulatory and in-clinic services. Dr. Keyser enjoys all aspects of equine medicine with a special interest in dentistry, reproduction, and sports medicine/podiatry. She currently owns 7 horses and 3 dogs. Dr. Keyser often spends her free time trail riding, hiking, camping, scuba diving, skiing, traveling, and competing in horse shows.
Teresa Duthie, DVM, MS
Equine General Practice

Dr. Duthie grew up a beach kid along the Treasure Coast in Stuart, FL. Her active involvement in the 4H Youth Organization and AQHYA further cultivated her love for horses. Growing up, she showed her horse in hunter competitions and later came full circle to serve as a riding instructor at the 4H Horsemanship School during her college summers. Dr. Duthie attended the University of Florida for all her academic training and received her B.S., B.A., MS, and D.V.M. from Gator nation. She was a musician in the UF Marching Band where she enjoyed playing and traveling to bowl games and championships. Can’t deny she bleeds orange and blue! In 2015, Dr. Duthie spent time at Rossdales Veterinary Hospital in Newmarket, England where her passion to work with horse athletes grew even more. Following completion of veterinary school, she completed an equine internship at Equine Medical Center of Ocala in Ocala, FL.

Her clinical interests include sports medicine and surgery, with a focus on orthopedic and upper airway disease. Outside of work, she enjoys staying active with running, swimming, hiking and extreme sports with friends like skydiving and bungee jumping.

Chelsea Linehan, DVM
Equine Intern

Chelsea Linehan grew up in Pheonix and received a Bachelors of Veterinary Science from The University of Arizona in Decemeber of 2013. She completed Veterinary School at Washington State University, earning a Doctorate of Veterinary Medicine in May of 2018. Chelsea has always loved veterinary medicine because it combines her love of animals and life sciences. This has grown over time to a love of being able to work with animals while also giving back. Horses have been very impactful on her life and she sees it every day in the lives of others. She loves giving back to both animals and their people, every day.

Chelsea is most interested in internal medicine, especially working with neonatal foals. In her free time she enjoys creative writing, cooking and watching too much television. She has a Paint mare named Sassafras (Sassy for short, Sassy-Pants for fun) who she has owned for 11 years. In that time, she has taught her patience, persistence, and how to keep balance when the ride gets rocky. She loves working with the team at Chaparral because she felt at home at the clinic. Combining great medicine, compassion, and mentorship - it is a wonderful place to continue growing as a doctor.

J Brent Rollins, DVM Emeritus
Dr. Rollins originally founded Chaparral in 1971 and retired at the end of 2012 after 45 years as an active practicing veterinarian. He is a 1967 graduate of Colorado State University where he received his DVM. He grew up in Phoenix, attending Osborn grade school, Washington High School and Arizona State University. His interest in horses came from his dad's Thoroughbred Racing Business (started on the end of a pitchfork and ended up with a trainer's license before Vet School).

After receiving his DVM, he served for three years as a captain in the US Army in Fort Detrick, MD. After the service, Dr. Rollins completed an Equine Internship at the University of California, Davis, Veterinary Teaching Hospital. In July 1971, he entered private equine practice in North Phoenix.
Dr. Rollins feels his greatest accomplishment is his family. Brent and Francie have been married since June 1st, 1963. They have five children and 25 grandchildren (at last count) and his days of retirement were spent keeping up with all their activities.

Dr. Rollins will be missed and forever memorialized as a part of our team at Chaparral. He passed away on January 27, 2018 surrounded by his loved ones.

Equine Technicians

Brooke Taranton
Inventory Manager
Equine Anesthesia Technician

Originally from San Diego, Brooke is a veteran member of the Chaparral team and has been with us since October 2008. Brooke is our lead equine technician and also performs anesthesia on horses and foals for a plethora of surgical procedures. Her love of horses began at the age of 3 and she has made horses her life. In her work life, she most enjoys the challenges of anesthesia and surgery. She loves to ride her horses and enjoys the comic relief of her donkey, Amos. She also has a soft heart for dogs. Needless to say, furry creatures have stolen her heart.
Krista Dupree
Imaging and Equipment Specialist
Equine Anesthesia Technician

Krista is an Arizona Native with a passion for horses as long as she can remember.  Krista has been with Chaparral since 2011.  She is an Equine Anesthesia Technician.  She is married and has three dogs and a horse.  She loves caring for rescue animals and every year she heads the Holiday Pet Festival hosted by Tranquility Trail Animal Sanctuary.
Emily Barrett
Clinical Coordinator
Equine Surgery and Medicine Technician
Emily grew up in the small town of Bull Valley, IL. She's been involved in the horse industry since she was 6 years old, starting with riding lessons and eventually spending every free second at the barn. Emily graduated in 2014 from William Woods University with a B.S. in Equine Science Equestrian Administration. She went back to Illinois after graduation and worked as an assistant barn manager at a local lesson barn, training horses on the side. In November of 2016, she found herself moving out to Arizona and got a job as a large animal technician at Chaparral. She spent some time as an ambulatory tech before moving in the hospital as the medicine technician. In her free time, Emily enjoys spending time with her Paint horse, Cruise, and her German Shepherd, Zazu. During the months when it's tolerable to be outside, you can find Emily hiking, trail riding, or just spending time outdoors.
Camila Reyes
Barn Nurse
Equine Anesthesia Technician

Camila was born and raised in Caborca, Sonora, Mexico. She attended veterinary school at Universidad del Valle de Mexico in Hermosillo, Sonora and graduated in December of 2017. She has always loved animals, mostly dogs and horses. She completed an equine externship at CVMC for 20 weeks over a year ago and we couldn't let her leave, we loved her so much. She has two dogs: a Shih-Tzu, and a Scottish Terrier (Sushi and Renata). She enjoys many aspects of equine medicine and has worked extensively with neonatal foals, surgical cases and she is now able to run equine anesthesia as well. In her free time, she likes to travel and spend time with friends and family.
Gina Stratton
Equine Ambulatory Technician

Gina was born in Big Spring, Texas. She grew up riding and showing in 4H and spent most of her life on racetracks, holding different positions at each one. This allowed her to travel to new places quite frequently. She misses the racetrack every single day, but when her son started high school, it was time to stop the nomad life. She took the opportunity to become an equine ambulatory technician at CVMC starting in 2016. It's a new experience for Gina and she hopes for more to come but still spend many weekends at the track. For Gina, there is nothing like making a difference in a horse's life. 
Victoria Ofstedahl
Equine Ambulatory Technician

Victoria is native to Phoenix, AZ. She has been involved with horses since she was 5 years old by riding, taking lessons, competing and participating in 4H. She has 5 horses of her own that she spends all her free time with. Victoria does local barrel races all over Arizona. She used to be a small animal technician but is now getting experience with large animals as an ambulatory technician. Victoria is attending Scottsdale Community College to get her certification through the Equine Science program and obtained her Associates Degree at Glendale Community College. Victoria loves spending time outside and spending time with friends. It has always been a dream of hers to be working at Chaparral and be able to help horses and their owners.


Brandt Cassel
Practice Administrator​​​​​​​

Brandt is originally from Southern California and has spent many years in healthcare management and operations positions. He has a BS in Organizational Management from the University of La Verne, and an MBA in Healthcare Administration from the University of Saint Mary. Brandt enjoys spending time with his dogs Loki and Elvira, and Lemmy the Cockatiel. He and his beautiful wife, Heather, enjoy beach camping and spending time with their two lovely granddaughters.
Holly Taranton
Practice Representative

Holly recently joined the Chaparral team and is enjoying our clients and her colleagues. She has a long history of administrative work in the legal, real estate development, construction and shopping center management industries and has always had a love of animals. She started off her oldest daughter at the age of 3 riding horses and her love of horses continued with her other 2 daughters. She now enjoys spending time with her husband, 3 grown daughters, her grandson and their many rescue dogs and horses. She, her husband, middle daughter, and grandson recently moved back to the United States from living in Melbourne Australia.
Nikki Fox
Practice Representative

Nikki has lived in Arizona her entire life. She always dreamed about working at Chaparral and was added to the team in June 2018. Growing up as a barrel racer she eventually added English riding to the mix. While learning to ride English, she found her heart horse named Money. Money was trained for saddle-seat but also shared her passion for barrel racing. When she is not with her horse or spending time with her 2 dogs, she usually can be found studying for school or with friends at a concert.
Tina Brea
Practice Representative

Tina moved to the Phoenix area in 1988 from the east coast with her husband. She has owned horses for most of her life and working for an equine veterinarian was always a dream of hers. Joining the team at CVMC in July of 2017 made that dream come true. Tina worked in the security/law enforcement industry until graduating from Long Medical's vet assistant program in 1993, which sparked her love of the veterinary field. She worked for the Maricopa County Sheriff's office in the Animal Cruelty MASH Unit for 7 years and one other local veterinarian for over 20 years.

In her free time, Tina's hobbies are spending time with her three fur babies: 2 toy Aussies and 1 Tibetan Spaniel, pet photography, flying her drone, driving her sports car and off-road trips in her Unimog with her husband.

Suzan Rockvam
Accounts Receivable Specialist

Suzan is originally from central California, but she has lived in the Scottsdale area for decades. She has always had a passion for animals and raised poodles and Lhasa Apsos in the past. She satisfied her equine passion by completing the Equine Science program at Scottsdale Community College resulting in a degree in Equine Science. Suzan spent many years as the office manager at Southwest Equine Hospital in Scottsdale. She was also employed in administrative positions in retail, real estate, health care and she now has returned to the veterinary world. She is the proud owner of 2 rescue dogs: Sally (a jet-black corgi mix,) & Sunny (a buff cockapoo mix.) Her many hobbies include fitness, music, and travel, but she spends most of her time enjoying her home and teenage son, Robert.
Merle Black

Merle recently came to Chaparral Veterinary Medical Center as our new bookkeeper. She recently moved to Arizona from Southern California after many years working in the non-profit sector. The need to assist our fellow man and four-legged friends never leaves our heart, which makes Chaparral a perfect fit for her.
Amy Goda-Dieguez
Barn Assistant​​​​​​​

Amy has been working with horses for 29 years in many different venues and has been fortunate to have traveled around the United States and the world. She started out working with and riding racehorses and her dream has always been to help care for horses. Amy also loves working with a passionate group of people who love what they do. She enjoys spending time with her wonderful daughter, Mae, and husband, Wilson, who also works at CVMC. 

Consulting Veterinarians

Zoe ReedEyeshine Veterinary
Eyeshine Veterinary

Dr. Reed is one of less than five-hundred veterinary ophthalmologists certified by the American College of Veterinary Ophthalmology in the world. Dr. Reed recently opened Eyeshine Veterinary: Arizona’s only locally-owned, independent ophthalmology-only practice treating ‘anything with eyes’ in Phoenix. She treats small patients at Eyeshine and provides ophthalmology services for horses both at local equine hospitals and in-the-field. In addition to seeing patients, she has authored a number of journal articles and continues to participate in clinically-focused research. Dr. Reed attended UC Davis for her DVM degree and completed her comparative ophthalmology residency here in the Valley of the Sun. Experience working in various ophthalmology practices and multi-specialty veterinary hospitals in the western United States inspired Dr. Reed to start her own veterinary ophthalmology practice where she can create an environment focused on caring for animals and the people who love them.