PETA Undercover at the Cleveland Clinic: Skulls Cut Open, Prolapsed Organs

Animals were injected with toxins that damaged their bodies, cut open with minimal pain relief, deliberately bred so that their internal organs would protrude outside their bodies, and kept in severely crowded cages. A worker even described preventable animal deaths there as “acceptable-ish.”

All this took place in the laboratories of one of the best-known and largest taxpayer-funded research facilities in the country.

PETA has conducted a six-month undercover investigation into the laboratories of the Cleveland Clinic, which, in 2019 alone, received more than $100 million in taxpayer money through the National Institutes of Health (NIH).

Skulls Cut Open

Experimenters at the Cleveland Clinic call it a “cranial window.” Less euphemistically, it’s a hole in a mouse’s skull exposing the brain and covered by a pane of glass.

Experimenters cut into the head, drill into the skull to expose the brain, and use suction to remove portions of it, exposing the hippocampus. A glass coverslip is placed over the exposed portion of the brain, and a stainless steel “head cap” is glued onto the mouse’s skull. The mouse receives pain relief only on the day of the surgery and the next day. These painful, invasive experiments are ostensibly carried out to monitor what happens to “the brain condition.” However, the “structure, function, and behavior” of the mouse brain has little relevance to the human brain.

Experimenters cut into the skulls of mice like this one and placed a glass coverslip with metal handles over the gaping wound.

Animals With their Insides Hanging Out

Experimenters at the Cleveland Clinic deliberately breed mice who are prone to pelvic organ prolapse—in which the uterus, bladder, or rectal tissue falls out of place and even protrudes outside the body. One mouse, named Daisy by PETA’s investigator, had a bloody rectal prolapse—a very painful condition in which part of the rectum protrudes from the anus. She had to drag her protruding rectal tissue through her bedding for at least 10 weeks, and she walked with her back legs unnaturally spread, appearing not to want to put pressure on her lower abdomen.

Daisy and other mice, some of whom had “enormous” prolapses, according to the experimenter’s aide, were bred repeatedly and denied pain relief. Asked about giving Daisy something to make her more comfortable, the aide replied, “No, there’s nothing.” She added that when mice like Daisy “just linger” and stop breeding, after a year of such misery, only then would they be gassed to death—which was ultimately Daisy’s fate.

An experimenter bred mice, like this one, to develop pelvic organ prolapse, a painful condition in which the uterus or rectum falls out of place and protrudes from the body. This mouse was denied any pain relief for at least 10 weeks.

Another mouse, named Lily, walked slowly and leaned forward with her legs spread widely apart because of her painful, untreated condition. Imagine a dog or cat being treated this way. But of course, mice suffer just as much as they do—the extent of their pain isn’t proportional to their diminutive size.

Paralyzed Mice Drag Themselves Along to Eat

Experimenters injected mice with a chemical that caused an inflammatory disease of the central nervous system, which left them struggling to walk and dragging their hind legs. Apparently, this is done to “model” multiple sclerosis—even though what happens in mice bears little resemblance to what happens in humans with the disease. The mice’s painful condition was expected, so, according to one worker, their agony went unreported to veterinary staff unless their paralysis also affected their front legs or they developed a skin condition such as urine scalding caused by the inability to move their back end.

PETA’s investigator saw that some mice suffering in this experiment lost strength in their lower limbs and could not walk at all. They had no choice but to try to crawl and drag themselves along in order to reach their food.

Experimenters cut into their backs and separated their muscles from their vertebrae so they could take images of their spinal cords.

Experimenters cut into the backs of mice like this one and separated their muscles from their vertebrae in order to take pictures of their spinal cords.

Kill Them 'Because They're Ugly'

Mice used in a kidney disease experiment developed raw, red, massive skin growths and lesions. One mouse scratched continuously at a growth that covered nearly half her face and kept pushing at her eye. When veterinary technicians told the experimenter that these mice were in pain, the experimenter apparently replied that they wanted to “kill” the mice “just because they’re ugly.”

One mouse had a sore stretching across his entire back, about 3 inches long. His hair was gone, and his skin was red. Another mouse had a thumb-size sore on her lower back covered by a thick scab. Yet another mouse had a 2-inch-long sore on his right side.

Experimenters manipulated the genes of these and other mice to make them prone to kidney disease. They also suffered from massive raw growths and sores on their skin.

A veterinary technician said that these mice were “scratching and biting the crap out of” the lesions, as mice used in the experiment “always” did.

But PETA’s investigator never saw these mice receive any treatment or relief for their wounds, such as anti-itch ointment or painkillers.

This mouse, who may have suffered from a misalignment of his teeth that made it difficult for him to eat but nevertheless went unnoticed, was found dead.

Animals Driven Mad by Extreme Crowding

Mice at the Cleveland Clinic were crammed into shoebox-size cages—up to five adult mice apiece or two adults with a litter of babies. Those housed alone in a cage fared no better—instead of companionship, they were given little more than a single paper towel.

Some mice at the Cleveland Clinic, like this one, who are highly social animals, were kept in isolation, without the companionship they need.

Staff often failed to remove litters or additional adults from cages before new litters were born. This led to trampling and even cannibalizing of the babies by their severely stressed parents in the intolerably unnatural conditions.

A veterinary technician at the Cleveland Clinic said that “in the grand scheme of things,” such deaths were “acceptable-ish.”

Other mice were simply left somewhere and forgotten.

Three mice were abandoned with no food or water in a cardboard bucket for hours. When no experimenter’s group took responsibility for them, a supervisor said that “it isn’t like they would get in trouble for it” anyway.

Six more mice were found abandoned in another bucket. Two were found in a cage bound for the garbage. One experimenter’s aide left a mouse gasping and laboring to breathe for more than an hour before she was finally euthanized.

Staff often failed to remove litters of ups from cages, which caused extreme crowding and stress, resulting in the deaths of newborns.

Pigs Used as Living, Breathing Practice Dummies

Other species at the Cleveland Clinic also suffered. Social, playful pigs were kept alone in barren pens. A worker said that some were used as “practice for new doctors,” while others were subjected to experimental rectal surgery.

In addition to rats and mice, the Cleveland Clinic imprisons rabbits, monkeys, pigs, hamsters, and other animals in its laboratories.

You Can Help these Animals!

PETA has submitted these findings to NIH and has requested an investigation. Please join PETA in calling on NIH to stop funding cruel experiments at the Cleveland Clinic, beginning with the Frankensteinian cranial window experiments.

PETA Undercover at the Cleveland Clinic: Skulls Cut Open, Prolapsed Organs

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