Santa Barbara Zoo Euthanizes Capybara Antonio
The zoo humanely euthanized Antonio after his health sharply declined while he was being treated for multiple myeloma, a rare blood cancer.
Updated on Nov. 1, 2026 in Pet Health
The Santa Barbara Zoo has humanely euthanized Antonio, a capybara who was battling multiple myeloma, a rare blood cancer that begins in bone marrow plasma cells. Antonio showed some signs of improvement over recent months, but his health declined sharply in his final days.
Why it matters
Antonio's case highlights the difficulty of treating cancer in exotic animals, where veterinary oncology protocols are still being adapted for species outside common companion pets. For Santa Barbara residents, it is a local reminder of the specialized medical care the zoo provides to its animals.
Antonio was born at the Montgomery Zoo and Mann Wildlife Museum on July 26, 2022, and joined the Santa Barbara Zoo in February 2023. The zoo has not released details on the specific chemotherapy regimen beyond its development with a local veterinary oncologist.
The players
Santa Barbara Zoo
The Santa Barbara Zoo is a Southern California zoo that houses a wide range of animals and maintains an in-house veterinary team for their medical care.
The details
The zoo's veterinary team developed a chemotherapy regimen with a local veterinary oncologist to treat Antonio's multiple myeloma. Antonio also faced progressive limb weakness that severely affected his quality of life before the zoo decided to humanely euthanize him.
Timeline
July 26, 2022: Antonio is born at the Montgomery Zoo and Mann Wildlife Museum.
February 2023: Antonio joins the Santa Barbara Zoo.
August: KSBY reports that Antonio is battling multiple myeloma.
Over the past few months: Antonio shows some signs of improvement under chemotherapy.
In his final days: Antonio's health sharply declines and he is euthanized.
Health Landscape
Antonio's case reflects the broader veterinary oncology work accredited zoos now undertake, where chemotherapy protocols built for companion animals are adapted for exotic species. Such efforts remain experimental, and outcomes vary widely across species and cancer types.
For Santa Barbara residents who visit the zoo, the story is a reminder that the institution maintains advanced in-house veterinary care for its animals. Families planning visits may see the zoo's medical work reflected in its ongoing animal care programs.
The takeaway
Animal cancer treatment is often more complex than it appears, and zoos rely on specialized partnerships to pursue it. Readers interested in animal health can follow how accredited institutions balance treatment hopes with quality-of-life decisions.
Further reading
Explore more on Pet Health in Santa Barbara for related coverage of animal care.
