On October 11, 2018, at 8:30 pm, a truck carrying 29 rhesus macaques arrived at a research facility in New Jersey. The monkeys began their journey at a National Primate Research Center (NPRC) in Oregon, one of seven federally funded laboratories and breeding centers located across the U.S. They were destined to be used in laboratory experiments, a practice that has been considered controversial for decades.
The NPRCs were created in the 1960s, using taxpayer money, to maintain a ready supply of primates for biomedical experiments. However, critics of these Centers assert that they have become increasingly out of step with scientific progress and the ethical concerns regarding primate use. Instead, they’ve become host to experiments with little relevance to human conditions, despite receiving millions of dollars in federal grants paid to individual researchers and costing thousands of nonhuman primate lives.
The facilities have been under scrutiny for years. Since the late 1990s, the NPRCs have been cited for ongoing lapses in animal care, as well as the overall welfare of the animals. In one instance in 2013, a veterinary inspector found multiple welfare violations at the Wisconsin NPRC—including 36 instances of monkeys escaping from their enclosure, five of which led to serious injury.
The inspector also documented numerous incidents in which monkeys were injured in laboratory housing. On June 4, 2013, a 2-year-old macaque was found dead in her cage. Medical records indicate that the animal’s head had been caught in “one of the chains attached to an enrichment device on the cage.” The year prior, a 7-month-old macaque died with their head stuck between the bars.
From the Breeder to the Laboratory
By the time they reached the New Jersey facility, the macaques had been confined in the dimly lit trailer for two days. When their crates were finally removed, one monkey was found collapsed and unresponsive.
The monkey, known as ID number 34597, later died of dehydration, prompting the U.S. Department of Agriculture (USDA) to issue a critical violation of animal welfare regulations to the transporter, JKL Secure Freight, according to documents obtained by Sentient Media. When the transport records were examined, they revealed that the monkeys had not been observed in over 10 hours.
This type of neglect is not unusual. From the breeder to the laboratory, the welfare of monkeys is repeatedly compromised, resulting in suffering, injury, and death. Another primate transporter, Stone Oak Farms and Transports, received a warning from the USDA in 2013 when they transported primates without first ensuring they had been given food and water.
Federal records of animal welfare violations at the NPRCs reveal that it’s not just the experiments that kill monkeys, but also widespread negligence. According to documents obtained by People for the Ethical Treatment of Animals (PETA), between January 2016 and December 2020, the NPRCs violated animal welfare regulations and guidelines 94 times. In one incident, seven baby monkeys died of anaphylaxis and sepsis after being exposed to a toxic dye used to mark identification numbers on their mothers.
In another, two monkeys were left in their cages and put through a high-pressure cage washer. One monkey was scalded to death; the other succumbed soon after. Staff caring for monkeys at these facilities have forgotten to feed them for extended periods of time, given the wrong medications resulting in death, and failed to provide pain medications for painful procedures.
There are currently seven NPRCs active in the U.S., located in Washington, Oregon, California, Texas, Louisiana, Wisconsin, and Georgia. For years, PETA and other animal rights organizations have been campaigning to end the “immeasurable pain, misery, and death” that PETA says monkeys face at these research centers.
Many of the monkeys raised in these facilities will experience transport and relocation throughout their lives, in what amounts to a lifetime of upheavals, disrupted social relationships, and unnatural physical and psychological stresses.
Suffering in the Monkey Supply Chain
For the past three months, Amy Meyer, PETA’s Manager of Primate Experimentation Campaigns, has pored through hundreds of veterinary inspection records obtained via Freedom of Information Act requests in order to better understand how and why primates suffer before arriving at testing facilities. The records document monkey transports all over the U.S. to numerous federal and privately funded laboratories, including from the NPRCs.
According to Meyer’s estimates, over 17,000 monkeys have been trucked to various laboratories in the U.S. between 2018 and 2021. Meyer points out this number is likely much higher, since the records PETA has received don’t document monkeys leaving states, but only those entering—and not all states retain copies of veterinary inspection records. For states like Florida and Texas with major monkey breeding facilities, the numbers of primates leaving these states are not always accounted for.
Meyer says these monkeys experience a never-ending “horror show” before they even reach the experimentation facility. “They are taken out of one cage, away from the only other monkeys they know, and shoved into a truck without a clue as to where they’re going. They’re trucked for hours until they get to a laboratory where they’re crammed into an even smaller cage, often completely by themselves,” she says. ”Just imagine what that does to these individuals.”
Transport is not only stressful for the monkeys. It also has profound physiological effects. Studies have shown that transporting monkeys by road results in negative effects on their immune systems, including suppression of T-cells and B-cells, which are crucial for the body to fight off infections. Monkeys transported between 21 and 24 hours have high levels of the hormone cortisol, indicating severe stress, and their immune systems don’t return to normal functioning even after 30 days at their new locations, which was the duration of the study. Negative effects could potentially persist for even longer.
Another study in the U.K. found that male long-tailed macaques exhibited disturbing behavioral changes immediately following international air travel, including displaying more negative behaviors and spending less time moving around. The monkeys, who were housed as a group in the study, also spent significantly more time hugging each other, a sign that researchers say means they were stressed and insecure. Additionally, the study found that some of the negative effects of transport were long-lasting, and the monkeys never returned to their normal, pre-travel behaviors.
According to Dr. Lisa Jones-Engel, a former primate field researcher at the Washington NPRC with decades of experience observing macaques in the wild, the animals that primate research facilities move around most frequently are young males because they are considered surplus, while females are valuable for breeding.
Under natural circumstances, Jones-Engel explains, these young males would leave their birth families and form bonds with other young male monkeys. These groups of tight-knit young males would then find another troop to accept them—an evolutionary strategy to ensure genetic diversity. But within the laboratory supply chain, those natural behaviors are disrupted.
“Emotionally, these young males are some of the most vulnerable,” Jones-Engel says. “And they were just miserable.”
Monkeys enter the U.S. laboratory supply chain in one of two ways: they are born at a breeding center, or they are either wild-caught or bred in overseas breeding facilities in countries like China, Laos, Vietnam, and Cambodia. Thousands of primates–over 26,000 per year according to Cruelty Free International–are imported into the U.S. to be used in laboratories, and they face long and harrowing transport from their countries of origin. Some don’t survive the trip or arrive weakened and ill.
In November 2021, an unknown number of long-tailed macaques died in the cargo of a Wamos Air plane carrying monkeys from Cambodia to the U.S. The monkeys were apparently destined for Envigo, a contract research laboratory, and had been on the plane for over 24 hours. Prior to their flight, they endured hours in small crates as they were driven to the airport.
“This example—only one of many—highlights that it’s not only the hours of invasive experiments that so-called ‘lab animals’ must endure,” says anthropologist Barbara J. King, author of Animals’ Best Friends: Putting Compassion to Work for Animals in Captivity and in the Wild. “It’s the whole horrible sequence starting right from the first moment of transport and then continuing day by day in captivity that tears their lives completely apart.”
Wringing Out the Last Bit of Life
In 2019, 68,257 primates were used in experiments in the U.S., including macaques, marmosets, squirrel monkeys, and baboons, according to the most recent numbers available from the USDA. An additional 40,269 were kept in research facilities but not used in experiments, for a total of 108,256 primates. More than 22,000 of these monkeys are held in the NPRCs.
Rhesus macaques represent over half of all macaque species used in research. They are often used in infectious disease research, obesity and nutrition experiments, and neuropsychological research, including experiments that induce stress and fear in both infants and adults. Most of them never get to retire. They are recycled into one experiment after another, moved from bonded pairs and social groups to solitary confinement, subjected to surgeries, drug injections, starvation, loneliness, and anxiety, and used until the last drop of vitality is squeezed from them.
Dorothy was one such monkey. Known as J353 or A15378, Dorothy was a rhesus macaque born in 1993 at a Texas breeding facility. She was kept in an outdoor enclosure with other monkeys and, for most of her life, she was repeatedly bred and gave birth to babies who were used for experiments. In 2010, she had surgery to remove a dead fetus from her uterus. In 2014, she experienced a painful, difficult birth that left her in shock and required medical treatment. Over 20 years, Dorothy had 13 infants taken away from her.
Dorothy’s veterinary records document repeated severe injuries during the years she was in the breeding facility. She was missing the tip of her tongue, both of her ear flaps were lacerated and torn, and she was missing the first digits of two of her fingers. Her body was covered in scars and her right hand had been fractured. Employees of the facility noted on one occasion that Dorothy was hunched on a crate and not moving, with wounds all over her body.
Jones-Engel explains that Dorothy’s frequent injuries were the result of “inhumane and uninformed management practices” at the facility that didn’t meet the social needs of monkeys. In their natural habitat, female monkeys form groups made up of family members—mothers, grandmothers, daughters. These related females band together for mutual protection and support. But monkey breeders often throw together unrelated females, which results in frequent fighting and victimization of low-ranking females like Dorothy.
“The whole system is just so screwed up,” says Jones-Engel. “There’s never going to be enough monkeys to maintain adequate genetic diversity, and the way they try to do it by having heterogeneous females in a breeding group completely destroys the social structure and leads to really bad outcomes for the moms and for the newborns.”
At 22 years old, Dorothy was taken from the only home she’d known and put into an experiment at the Washington NPRC led by Elizabeth Buffalo, professor and chair of the Department of Physiology and Biophysics at the University of Washington. Jones-Engel points out that previously at the breeding facility, Dorothy lived outside with some access to sunlight and air. Then, she was loaded onto a truck and hauled up to Washington, where “for the first time in her life,” Jones-Engel says, “she was placed in an indoor cage.”
Dorothy was so mistrustful that when she was introduced to other monkeys within the confines of a tiny cage, she became defensive. “It’s like putting two of us who’ve never met in seats on a plane. And you’re there forever—you eat there, you eliminate there, you spend all your time in that row with that other person. It’s no wonder it’s chaos,” says Jones-Engel.
Eventually, the Washington NPRC gave up on finding companionship for Dorothy, and she spent her remaining two-and-a-half years alone. During the course of Buffalo’s experiments, she wore a heavy metal collar, spent hours in restraint, and was refused food and water until she performed certain tasks. A titanium head post was permanently glued to her skull so she could be held immobile in a restraint chair. Despite Dorothy not eating, pulling out most of her hair, experiencing bloating and lethargy, and losing 20 percent of her body weight, the experiments continued.
Dorothy’s condition became so dire that she was finally euthanized after she endured months of debilitating illness in addition to the experimental harms.
The Failure of Primate Experiments
Though considered a cornerstone of biomedical research for decades, experiments in nonhuman primates have failed to yield promised results, and there is a growing ethical concern among the U.S. public regarding the use of animals in experiments. Over 50 percent of respondents surveyed by the Pew Research Center in 2018 opposed animal experimentation.
The scientific community has been slow to adapt. In 2015, under rising public pressure, the National Institutes of Health (NIH) announced it would no longer fund research using chimpanzees. This decision finalized the process of phasing out chimpanzee research based on recommendations from a 2011 commissioned report that concluded most of the current uses of chimpanzees in experiments were “unnecessary.”
That same year, after multiple incidents demonstrating systemic neglect and mistreatment of monkeys, including the death of a monkey from dehydration when employees forgot to provide water, Harvard University also decided to close the New England NPRC. However, research on other primates, like macaques and marmosets, continues unabated, despite raising many of the same ethical and scientific concerns.
Primates have complex social, psychological, and physical needs that are not met in laboratories, and experiments on ailing, stressed, and physiologically compromised monkeys have failed repeatedly to yield clinically useful vaccines and treatments.
Primate models of human diseases have fallen short due in large part to the many physiological and genetic differences between humans and other primates.“When you’re using animals as so-called models for human disease, they’re already by nature artificial models because diseases are artificially induced in animals and are not the same as what naturally occurs in humans,” says Dr. Aysha Akhtar, co-founder and CEO of the Center for Contemporary Sciences. “We shouldn’t even use animal models as a term. We should always be saying artificial animal models because that’s what they are.”
Akhtar also points out that the differences between humans and other primates are profound. “The main rationale for using nonhuman primates is that they’re our closest genetic cousin. Well, closest genetic cousin isn’t close enough,” she says. “There’s a reason why a monkey looks like a monkey. What we see in outward appearance alone is a result of numerous, sometimes very subtle differences in genetic expression, biochemistry, and molecular biology.”
Akhtar cites HIV vaccines and Parkinson’s disease treatments as just two examples of the failures of primate use. In the case of HIV vaccines, more than 30 candidates had been developed in primates that were subsequently ineffective in humans. Two of the vaccines actually increased HIV risk in humans. Similarly, for Parkinson’s disease, primate research has not yielded any significant treatments that address the fundamental disease. She explains that nonhuman primates don’t get Parkinson’s disease, and experimenters must artificially induce the disease in monkeys, which just mimics some of the symptoms that humans get.
“Researchers have again and again used taxpayer money and a lot of animal lives for research that ends up being incredibly fruitless,” says Akhtar. “In the meantime, we have people with Parkinson’s disease and people who are at risk of HIV, who arguably could have been better treated if we stopped using these ineffective and artificial animal testing methods.”
After witnessing the treatment of monkeys in laboratories at the Washington NPRC and the failure of the University of Washington’s animal oversight committee to ensure the highest standards of welfare and scientific integrity, Jones-Engel resigned from her position and joined PETA as a senior science advisor. She believes that getting rid of the NPRCs is a crucial step in improving biomedical research, cutting out financial waste, and creating a more humane system of scientific inquiry. She is confident that, like the defunct New England NPRC, the other NPRCs will soon be closed down.
Akhtar agrees that primate experimentation is on its last legs and questions why biomedical research would continue on a path doomed to failure, rather than embracing animal-free methods. “Fortunately, there is a growing momentum within the scientific community itself,” she says. “More and more scientists are calling out the unreliability of animal experiments and saying we need to get back to studying human biology.”
Disclosure: Ingrid L. Taylor is a former veterinary science advisor at PETA. The Washington and Oregon NPRCs were also contacted but declined to comment on the investigation.
Ingrid L. Taylor is a writer, poet, and veterinarian whose work explores strategies for fostering multispecies solidarity and deconstructing speciesism. She has worked in clinical veterinary medicine and public health.