Our Careteam

Dr. Susan Olivas
Owner, Veterinarian
By the time she was 12, Susan had grown too tall to be a jockey. She considered what else she could do with her love of animals and her scholastic abilities, and a career as a veterinarian was the perfect answer! From then on she focused on becoming a veterinary professional.

Dr. Olivas attended the University of California Davis to obtain her Bachelor’s in Animal Science. After working at the University’s Teaching and Research Facility, she was accepted into the School of Veterinary Medicine, where she chose the Large Animal Medicine tract. After graduating in 1989, she focused on Equine medicine for the first 10 years of her career. When she was ready to start a family with her husband Mike, she switched to small-animal medicine and has been working in that field for the past 20 years. In 2012, she purchased Ceres Veterinary Clinic.

Dr. Olivas’s family consists of her husband and their three boys, Aaron, Daniel, and Jacob, who are involved in soccer and basketball. The family also has three cats, two horses, an assortment of chickens, sheep, and their newest addition is an Australian Cattle Dog named Happy.

As a busy working mother, Susan’s spare time is spent following her children’s sports and hobbies. When she does get a few moments to herself, she likes reading and going on walks.
Dr. Ingrid Judge
Dr. Ingrid Judge is a graduate of the UC Davis School of Veterinary Medicine. Dr. Judge first became interested in emergency medicine while completing her PhD degree in Comparative Pathology at UC Davis. Dr. Judge trained in emergency medicine in the West Los Angeles area and then worked in a Level 1 emergency facility for many years. Dr. Judge enjoys spending her spare time with her family on a cattle ranch in the Sierra foothills.
Dr. Erin Cassiday
Associate Veterinarian
Erin Cassiday’s veterinary medicine career path began when she was six years old. Even at that young age, young Erin was virtually certain she wanted to become a veterinarian someday. To get a taste of the profession, Erin happily accompanied her equine veterinarian on local farm calls, and those experiences cemented her desire to work with animals. Today, Dr. Erin Cassiday has achieved her childhood veterinary medicine goal. She loves helping her furry patients to live longer, healthier lives with their pet parents!

Erin spent her early childhood in Florida with her sister and mother, and moved to Arizona when she was 11 years old. A confirmed animal lover, Erin acquired cats, dogs, horses, a pot-bellied pig, and birds as her companions. Her family’s property also contained numerous cattle and buffalo. When the family veterinarian visited Erin’s farm to examine and treat the animals, Erin often “played veterinarian” right along with him. She also “rescued” numerous animals who seemed like they needed a helping hand. Erin’s veterinary medicine dream was still very much alive.

After Erin graduated from high school, she attended Arizona State University, majoring in both biology and agribusiness. After her graduation, Erin entered veterinary school, and after much hard work graduated in the top 15 percent of her class. Dr. Cassiday credits her family and friends, along with her former equine veterinary mentor, for encouraging her to achieve the career she had dreamed about.

With her Doctorate of Veterinary Medicine in hand, Dr. Erin Cassiday joined a mixed animal practice, a hectic job that required many on-call emergency shifts. Desiring a more normal schedule, Dr. Cassiday joined the Ceres Veterinary Clinic care team in April 2014. She loves helping her clients to keep their pets healthy; and she also enjoys using her diagnostic tools and treatments to resolve her furry patients’ medical problems.

Away from the hospital, Dr. Cassiday and her boyfriend, Ronny, enjoy camping with his large family. The couple also indulges their love for good food and wine on frequent trips to the California coast. Dr. Cassiday thrives on travel to new places, and she often seeks ways to share her veterinary medicine knowledge at her destination. Most recently, she traveled to Nicaragua with World Vets, teaching veterinary students valuable surgical and general medicine skills while also helping to care for residents’ animals.

Dr. Cassiday also shares her home with two much-loved furry family members. In 2017, she rescued Mr. Moustachio, a handsome but playful cat who has a very distinctive moustache. He fit right in with the family and loves his dog “sister” Hallie. Hallie, a Queensland Heeler with a hobby of “stalking” people through the house, provides great entertainment for Dr. Cassiday and Ronny. While Hallie has her playful side, she has also helped to save several animals’ lives as a canine blood donor.
Dr. Anita Roussell
Associate Veterinarian
Dr. Anita Roussell began her collegiate career studying communications, and worked in the human resources field for several years after graduating with her degree. Eventually, she started to realize it wasn’t her true calling. When Dr. Roussell thought back to what made her truly happy, she had a realization: she wanted to spend her days bettering the lives of animals as a veterinary professional!

Dr. Roussell grew up in Turlock, California and started veterinary school in 2006 at the University of Illinois, Urbana-Champaign. Upon graduation in 2010, she moved back to California with her husband in order to be closer to family. Having known Dr. Olivas from her time working with her at another clinic, Dr. Roussell jumped at the chance to team up with her again—she joined the Ceres Veterinary Clinic family in 2019 and hasn’t looked back since.

Around the hospital, Dr. Roussell enjoys educating pet owners about their companions’ health and behavior. She also loves to build meaningful relationships with the area’s pet owners, her four-legged patients, and her talented coworkers.

Outside of work, Dr. Roussell likes traveling, reading, gardening, baking, practicing yoga, and spending time with her friends and family. She and her husband have one dog, Cooper, who loves every single person or animal he comes across.
  • 57
  • Pet Cartoons
  • Pet Portal Login
    • Jennifer Purdom FortuneJennifer Purdom Fortune

      Dr. Cassiday and the rest of the staff are amazing!! One of my dogs suffers from seizures. Originally he was having 2-3 seizures every 3-4 weeks and there was a point last year where we didn't think he was going to make it. Dr. Cassiday worked hard to find a combination of medications that would work for our little guy. We just got home from our annual check up. I am happy to report Kilo is doing great and is 3.5 months seizure free. I can't thank everyone at Ceres Vet enough for everything they do!

    • Leona BreckLeona Breck

      Wonderful caring staff! Very good with nervous animals. Excellent treatment.

    • Beth SlavinBeth Slavin

      when we got our 6 week old Bassett hound we thought we had a healthy pup four days of having her she was sick and no vet would take us in Dr Cassidy welcomed us. none of us thought she would survive but here it is 2 years later and miss copper is healthy. Then we had to bring in our english mastiff with possibilities of having to either amputate or put her down. today miss molly mae is fully recovered with all four legs.

    • Leslie TaylorLeslie Taylor

      Best vet around. Wonderful, caring staff, and doctors are great!

    • Sherry BallietSherry Balliet

      Very loving and caring staff
      I absolutely love Dvm Susan Olivia’s

    • Sam MendoncaSam Mendonca

      I have found the staff has always been very friendly and helpful. THEY CARE about the animals that are brought into the clinic.

      I would never take my dog anywhere else.

    • Josephine RodriguezJosephine Rodriguez

      The staff was very friendly and helpful.