An animal welfare group wants federal regulators to fine Duke University over the deaths last October of four rare aye-ayes at the Duke Lemur Center.
The group, Stop Animal Exploitation Now, said Thursday it’d filed a complaint with the U.S. Department of Agriculture. Spokeswoman Stacey Ellison said it believes the incident, attributed to poisoning from a natural toxin in avocados center staff fed to the lemurs, was preventable.
Animals in captivity “should only be fed things [their keepers] know won’t hurt them and that they eat in the wild,” Ellison said.
Ellison’s group was reacting to regulatory filings by Duke and the National Institutes of Health, whose Office of Laboratory Animal Welfare helps the U.S. government keep tabs on the treatment of animals at federally-funded universities.
The four aye-ayes died suddenly in late October. The incident, shocking to Lemur Center staff and Duke officials generally, prompted an investigation into its causes that roped in experts at Duke, Michigan State University, N.C. State University and the U.S. Centers for Disease Control.
All four of the victims, and a fifth aye-aye who took sick but survived, had similar symptoms. Necroscopies of the dead animals showed they had fluid around their hearts, and tissue samples showed they had damage to their heart muscles.
Lab tests at Michigan State found the avocado toxin, persin, in samples of the stomach contents of three of the four victims.
Persin is known to harm several kinds of birds and mammals, including some common farm animals. But until the Duke incident there was no sign in the literature that it could similarly affect primates, the order that includes lemurs, apes and humans.
“This was an unanticipated reaction, as avocados have been fed to captive lemurs around the world for many years and were fed to other aye-ayes at Duke that day who remained unaffected,” said Michael Schoenfeld, Duke vice president for public affairs and government relations.
Schoenfeld noted that center staff have since removed the fruit from the lemurs’ menu. He also objected to the characterization, by Ellison’s group, that the incident was the result of “negligence.”
“The aye-ayes and other endangered lemurs in Duke’s care are here for three purposes: conservation, education and non-invasive research,” he said. “Duke’s commitment to preserving and protecting these animals and their native habitats in Madagascar dates back more than 50 years at this point. Any suggestion that Duke is willfully or even negligently harming the lemurs in our care is deeply misguided.”
Duke reported the incident to federal regulatory in December. On Jan. 5, NIH staffer Neera Gopee wrote back to say her agency’s Office of Laboratory Animal Welfare “found no cause for further action” by the government.
In taking avocado off the lemurs’ menu, the university took “appropriate measures to correct and prevent recurrence of this adverse event” said Gopee, a veterinarian and University of Georgia-trained toxicologist.
She added that Duke’s “prompt and thorough resolution of this matter is commendable” and consistent with the NIH’s expectation that universities like it police their staff’s treatment of animals.
In December, Lemur Center veterinarian Cathy Williams said that while avocado had “been introduced to Madagascar as a [non-native] food item,” there was “really no information as to whether wild aye-ayes would eat” it.
At the Lemur Center, avocado had been part of their feed since at least 2013.
Based in Cincinnati, Ohio, Stop Animal Exploitation Now is one of several animal-welfare groups that monitors federal filings to watch for unexpected animal deaths or cases of mistreatment.
Its previously filed complaints against UNC-Chapel Hill, and on Thursday said its complaint about the lemurs also addressed the deaths at Duke of a macaque and a mouse, and a non-fatal injury to a second macaque.