Inspection of UC Davis facility reveals monkey fights, one sparked an amputation
Animal rights activists are questioning the University of California, Davis, after potentially preventable fights among monkeys kept at the California National Primate Research Center were highlighted in a routine federal inspection report.
The U.S. Department of Agriculture discovered that several fights between macaque monkeys were potentially caused by human error during its routine inspection on March 4, according to the inspection report.
A 14-year-old male monkey suffered lacerations to his face and shoulders, according to the inspection report, requiring stitches. The injuries occurred after a staff member opened the door between two enclosures with monkeys that were not compatible, causing the fight.
In another case, a female monkey escaped her cage due to a welding failure, according to the inspection report. That monkey then fought with another monkey, causing injuries to the monkey’s face and hands that required amputations. The injured monkey was monitored in the hospital after the incident and ultimately released to its enclosure.
The facility was also found in violation of the Animal Welfare Act, according to the inspection report, by placing animals in cages smaller than required by federal regulations. The USDA inspection found that UC Davis at times kept two monkeys in an 8.6-square-foot space when a 10.3-square-foot enclosure was required.
The March inspection was the first USDA report documenting violations at the facility since July 2025, according to federal inspection records. Since inspections resumed following COVID-19 disruptions in 2021, UC Davis has received 15 violations across nine inspections, including critical violations involving animal injuries and enclosure failures.
People for the Ethical Treatment of Animals criticized the UC Davis facility after reviewing the latest report, which was published April 8, saying the conditions caused “terror and suffering.”
“The bloody fights and serious wounds these monkeys sustained represent more than regulatory breaches — they lay bare the reality that monkeys are crammed into small cages and forced to live under conditions so oppressive that injury, terror and suffering are unavoidable,” PETA spokesperson Tas Bruner wrote in a statement Wednesday.
In a statement, UC Davis spokesperson Andy Fell said the institution aims to provide the best care possible.
“Animal research benefits human health and is strictly regulated,” Fell wrote in a statement. “We strive to provide the best possible care to animals in our charge.”
The university uses primates to research HIV/SIV, Zika virus, aging and Alzheimer’s disease and respiratory diseases, according to Fell. These macaque monkeys are native to Asia and North Africa.
Such experimentation on primates is controversial, but researchers see it as necessary given the animals’ similarity to humans. Treatments for diseases such as polio and measles were first tested and developed using primates.
This story was originally published May 7, 2026 at 8:58 AM.
