Waka Blair, DVM, CVA, CVBMA, CVFT, CCRP

Owner

Dr. Blair owns Acorn Veterinary Clinic. She first joined Acorn in 2002 as a receptionist and volunteer veterinary assistant.  Then she worked as a registered veterinary technician and Small Animal Renal Transplant Coordinator at UC Davis Veterinary Medical Teaching Hospital before entering UC Davis School of Veterinary Medicine, where she graduated with honors in 2010. Following graduation, she completed internships in small animal medicine and surgery at Texas A&M University and in emergency and critical care medicine at UC Davis. She furthered her studies in Traditional Chinese Veterinary Medicine (TCVM) at Chi University while working at a busy after-hour emergency clinic and rejoined Acorn as an associate veterinarian in 2015. Dr. Blair holds certifications in acupuncture (CVA), Balance Method acupuncture (CVBMA), food therapy (CVFT) through Chi University, and canine rehabilitation (CCRP) through University of Tennessee, and has additional training in Palliative and End-of-Life Care and veterinary Tui-na (Chinese medical manipulation). Her professional interests include animal physical rehabilitation and integrative medicine. Born and raised in Japan, she is fluent in both English and Japanese. Outside of work, she enjoys spending time with her husband, daughter and two furry children.  She also loves skiing, swimming, practicing Hapkido (a form of Korean martial art mentored by Master Rick Schubert), vegetable gardening, watching and reading Japanese anime and manga.

Read more: A Path of Purpose: How Dr. Blair Realized the American Dream at Acorn Veterinary Clinic

Amy Wolfe, DVM

Medical Director

Dr. Wolfe joined Acorn in early 2018. With roots in Hawaii and Canada, she came to Davis for veterinary school and decided to make it her home after graduating in 2009. Since then, she has worked in general practice, primarily in Fairfield, while also supporting clinics and shelters near Davis. Dr. Wolfe has a broad range of interests within general practice, from dermatology and dentistry to surgery, radiology, and ultrasound. Since joining Acorn, she has become an integral part of the team, overseeing medical operations, establishing protocols, and helping maintain quality of care across the clinic.

Outside of work, she enjoys spending time with her family, which currently includes two children and three pets (the number of four-legged members may vary!). She loves traveling with her family, especially relaxing on Hawaiian beaches, and enjoys watching sci-fi movies and cooking.

Andrea Kirsch, DVM

Education Director

Dr. Kirsch, from Ventura County, California, was inspired to pursue a career in veterinary medicine by her experience as an equestrienne in her youth. She graduated from the UC Davis School of Veterinary Medicine in 1988. During her undergraduate and first year of veterinary studies, she competed for the Cal Aggie Cyclists bike racing team, where she met her husband, Doug. They still enjoy weekend bike rides, swimming, and walks with their Jack Russell cross, “YoYo.”

Dr. Kirsch has practiced small animal medicine in Northern California since graduating and started Natomas Veterinary Hospital in Sacramento in 2006, which she owned for 15 years. She later worked with the Primary Care Service at UC Davis Veterinary Medical Teaching Hospital, mentoring fourth-year students with general practice cases. At Acorn, she plays an essential role in training and mentoring staff at all levels. Her professional interests include general wellness care, ultrasound, anesthesia, dentistry, and exotic animal medicine. Dr. Kirsch is passionate about providing high-quality veterinary care in a friendly, upbeat environment and loves educating clients about their pets’ health.

Kim Nixon, DVM, MPVM 

Dr. Nixon earned her veterinary degree from UC Davis in 1985, and her Masters in Preventive Medicine the following year. She has worked at Acorn since 2005. She has a special fondness for exotic pets, and enjoys treating birds, reptiles, and small mammals, in addition to cats and dogs. She loves her pets, her garden, cooking and quilting. She has three children and lives in Davis.

Tracy Alexander, DVM (she/her/hers)

Dr. Alexander grew up in Riverside and moved to Davis for her undergraduate studies in 2001. She ended up loving the town so much she made it her permanent home! She is twice a graduate of UC Davis (BS 2003, DVM 2010) and practiced in Shasta County and Rancho Cordova before joining the Acorn team in January 2019.  Dr. Alexander is interested in all aspects of general practice but especially likes focusing on preventive medicine, including heartworm disease prevention. In her recreational time, she and her husband love taking their two young sons backpacking in the Trinity Alps.

Katy Siquig, DVM, MPVM

Dr. Siquig grew up in northern California and graduated from Princeton University, obtaining a degree in cultural anthropology.  After a few years of work, she attended vet school at the University of California at Davis, graduating in 2010.  She has worked in and around the Sacramento region in small animal practice for over a decade.  She also returned to UC Davis in 2018 and obtained a Masters of Preventive Veterinary Medicine (MPVM) in 2020, completing a project that focused on a time series analysis of seabird strandings along the California coast.  In practice, Dr. Siquig has a particular interest in feline medicine, pain management, and geriatric care for both cats and dogs.  She is a member of both AVMA and CVMA. She enjoys any time spent outside, particularly backpacking in the Sierra mountains and visiting the California coastline. Travel highlights include trips to New Zealand to kayak and several trips to Ladakh in northern India for trekking, as well as a rim-to-rim hike of the Grand Canyon in 2021. Other interests include gardening, swimming, and reading a wide range of fiction.

Carla Weinberg, DVM

Dr. Carla Weinberg is a true "California Girl"-- raised in the Fresno area and attended Occidental college in Los Angeles.  Wanting to try something different, she moved to Illinois for graduate school in Physiology and received a Master’s degree there but realized her heart was in California so she returned home.  She received her Doctor of Veterinary Medicine from UC Davis in 1997 with a focus on small and exotic medicine.  Dr. Weinberg lives with her husband, 2 dogs, 3 cats and 1 cockatoo (Bobby).  She is interested in the human/pet bond and quality of life for the owner and their furry, feathered and scaled family members.   She loves time with her kids and husband, water sports, bike-riding, reading and traveling.  She can't wait to meet you and your pets!

Rick Bertsch, DVM

Dr. Bertsch earned his veterinary degree from UC Davis in 1986 and has been a member of Acorn Veterinary Clinic since 2005. With a primary focus on surgery, he has also contributed his skills to the Humane Society and Yolo Shelter. A longtime Davis resident, Dr. Bertsch shares his home with a diverse array of animals, including cats, dogs, guinea pigs, rabbits, tortoises, and donkeys. He holds an undergraduate degree in Earth Science from UC Berkeley, where he studied geology, paleontology, and anthropology. Passionate about understanding and addressing climate change, Dr. Bertsch spends his free time reading about history and anthropology and enjoys time with his daughter.

Addison Cheng, DVM

Dr. Cheng grew up in Arcadia, California where his love for animals was first introduced by his mom. In high school he decided to pursue a career in veterinary medicine and moved to Davis in 2016 to study Animal Science. He obtained his B.S. in 2020 and went on to earn his doctorate at the UC Davis School of Veterinary Medicine in 2024. Dr. Cheng's professional interests include cardiology, surgery, and dentistry. He is passionate about building relationships with clients and partnering with them to meet the needs of their pets. Addison is excited to start his career at Acorn and to serve the local community of pets and their owners.

Outside of the clinic, Addison enjoys serving at his church with his wife. He also enjoys playing music and spending time with friends.

Ronald Koh, DVM, MS, DACVSMR, FACVBM, CVA, CCRV, CCRP, CVMMP, CVCH, CVFT, CVPP, CHPV

Dr. Koh, a Malaysia native, earned his veterinary degree in Taiwan and has been practicing in the United States since 2009. He is a board-certified specialist in veterinary sports medicine and rehabilitation with extensive expertise in pain management and integrative medicine. He is deeply passionate about improving animal mobility, managing pain, and enhancing quality of life through rehabilitation and multi-modal holistic approaches. Dr. Koh holds multiple certifications, including veterinary acupuncture, rehabilitation, pain management, medical manipulation, herbal therapy, food therapy, as well as hospice and palliative care. He is currently a full professor at Chi University. Previously, he served as a clinical associate professor and chief of the Integrative Medicine Service at the UC Davis School of Veterinary Medicine. Dr. Koh has authored numerous book chapters and peer-reviewed publications on topics such as acupuncture, Traditional Chinese Veterinary Medicine (TCVM), rehabilitation, pain management, laser therapy, and integrative medicine. He is fluent in multiple languages, including English, Mandarin, Hakka, Cantonese, and Malay. In his personal time, Dr. Koh enjoys traveling and exploring new places and cultures. 

Joy Jackman, DVM

Retired

Sally Borges, DVM, MSc

Retired