(The influential Institute of Medicine (IOM) has labeled nearly all chimpanzee research as scientifically unjustified. | AP)

Tan belly pressed to glass, Torian, a thigh-high, four-year-old chimpanzee with a freckled face, wants to be scratched.

When his veterinarian pretends to tickle Torian through the thick pane, the chimp bounds onto a hanging chain, squealing. Showing off, his cagemate Tiffany performs a handstand, pressing her butt to the glass. With the endless energy of children, they swing and climb, roll on the floor, and chew blankets and rubber balls.

The pair are, in a sense, the last of their kind: Just four chimps remain at this controversial research facility near Interstate 270 in Rockville. Called Bioqual, the company’s 30-year run of chimpanzee research is ending, victim of a historic shift away from using apes in medical experiments.

On Monday morning, a truck hauled six chimps from Bioqual. Last week, five others were removed. The last four, including Tiffany and Torian, will depart later this summer.

They are returning to where they were born — the much larger New Iberia Research Center, part of the University of Louisiana at Lafayette — where they will be available for more research before they’re retired — someday — to a sanctuary.

“This is another indication that chimpanzee research is on the decline,” said Kathleen Conlee of the Humane Society of the United States, which has painted Bioqual’s chimp research as unethical.

While about 1,000 research chimps live in the United States — down from 1,500 in 1997 — a landmark report from the influential Institute of Medicine (IOM) last December labeled nearly all chimpanzee research as scientifically unjustified.

The final National Institutes of Health-funded experiments at Bioqual tested vaccines against norovirus and respiratory syncytial virus, two studies pointedly called out in the IOM report as unnecessary. Chimps are no longer needed for such work, the report said.

Drug companies, which also fund some chimp research, are also backing away from the practice as lower-cost, higher-tech alternatives emerge.

Video spurs change

For animal-rights activists, the departure of the Bioqual chimps represents a victory; they’ve been agitating to close the facility for decades.

In 1986, activists calling themselves “True Friends” broke into the unmarked, single-story building and stole four infant chimpanzees. They filmed chimps and monkeys stuffed into metal cages the size of ovens — stark footage soon seen by millions on the national nightly news.

The ensuing public outcry galvanized the burgeoning animal rights movement, said Kathy Guillermo of PETA. “The exposure of those horrors led to so much of the reform we’ve seen today.”

John Landon, who had just taken over the company — then called SEMA Inc. — endured a year of protests at his house and threatening late-night phone calls.

Under intense pressure from activists and the Agriculture Department, which regulates animal research, Landon invited Jane Goodall — that human face of the plight of the chimp — to the lab.

She visited. She cried.

Then she worked with Landon to improve the lives of the Bioqual chimps.

In the late 1980s, Bioqual tore out the small metal cages and built roomier, nine-foot-tall enclosures, whose glass walls allowed the great apes to see, gesture at and vocalize with their neighbors — and their keepers. The staff added toys and swings on plastic-covered safety chains. They moved two TVs outside the 26 enclosures — TV’s that are still there. Next to one rests an old VHS tape of an animated Tom Sawyer and Huck Finn tale.

“Some of them like animal shows and cartoons,” said a Bioqual veterinarian, who’s worked at the company for a decade. He asked for his name to be withheld to avoid harassment from activists.

“It’s like child care,” said Landon, who invited a Washington Post reporter to the facility this week but prohibited photography.

As Torian pulled himself head-first into a hanging red bucket, feet flopping out, Landon sarcastically remarked, “They look miserable, don’t they?”

During a half-hour visit, though, the young ape also behaved like a caged animal — banging on the glass walls, tearing around in circles, pressing his back into a corner.

Brought in as youngsters

The hundreds of chimps that passed through here typically arrived as two- or three-year-olds. (Wild chimps, in contrast, nurse until age five or six). They were routinely sedated; injected with experimental vaccines; and stuck for blood and swabbed for mucus.

Younger chimps were trained to present a thigh for injections. Older, stronger chimps sometimes needed to be “squeezed,” the veterinarian said — drawn into a cage with collapsible sides.

Bioqual never performed more invasive procedures like surgery, said the veterinarian.

The staff raised the chimps, rolling around with them in the now-fallow playroom. Landon pulls back the curtain to the room for a few seconds. It’s like a day-care center: Balls and toys lay scattered on the floor, while bright paintings of Scooby Doo and other characters adorn the walls.

But animal-rights activists have long argued that keeping chimps in the facility is cruel. After the release of the IOM report last year, the battle heated up. PETA bought $1,000 in Bioqual stock to get a seat at shareholders’ meetings. The Humane Society of the United States posted ads in Metro trains displaying the face of a chimp and the line, “Bioqual . . . conducts experiments using young chimpanzees. If you have witnessed poor animal treatment there, call” the Humane Society.

Then in May, another activist group, the Physicians Committee for Responsible Medicine, escalated the fight: They filed a petition with the Agriculture Department, asking for an investigation into alleged violations of the Animal Welfare Act, which requires labs to “promote the psychological well-being” of chimpanzees. The enclosures were still too small, the group said: about the footprint of an office cubicle, 64 square feet. The chimps had no access to the outdoors. And they were often housed alone.

Landon responded by inviting representatives of the Humane Society and PCRM to the facility.

In late May, a surprise visit from USDA inspectors found only one minor issue, said Dave Sacks, spokesman for the agency’s enforcement office: Too many cockroaches.

Two years ago, though, NIH found more serious problems. Bioqual was housing too many of its primates — social animals — alone, instead of in pairs or groups as generally required by the Animal Welfare Act and NIH regulations.

Patricia Brown, director of NIH’s Office of Laboratory Animal Welfare, said the agency had been concerned about inadequate housing of Bioqual’s 1,000-plus rhesus macaques, schnauzer-sized monkeys heavily used for medical research.

“We never had a concern about the chimpanzees,” said Brown. By 2011, Bioqual had fixed the macaque housing, she said. “We accepted the changes they made and gave them a quite commendable response at the end.”

No room to run

During a visit this week, two of Bioqual’s four chimps were housed alone. Ricky, a brawny eight-year-old male, lolled on a table, listless, while a younger, smaller chimp, Loretta, climbed around her enclosure next door.

“If we put [Ricky] in with Loretta, he’ll beat up on her,” said the veterinarian. “They have to assert their dominance. In the wild they have room to run. Here they don’t.”

Brown said NIH accepted Bioqual’s reasons for housing some of its chimps singly.

While the housing issue is closed, the USDA does have an open investigation of Bioqual.

In May 2011, an eight-year-old chimp died during transport from Rockville to New Iberia Research Center in Louisiana, which owns the chimps housed at Bioqual.

“He was fine when he went out of here,” Landon said. He points to the shipping company, Stone Oak Farms and Transports, of Opelousas, La., and NIH, which hired the firm, as responsible. “This is totally NIH’s problem,” he said.

Officials at Stone Oak Farms and Transports did not return calls.

NIH responded to the death by switching trucking companies.

The truck that hauled six chimps away on Monday carried a technician and a veterinarian, said Landon, who watched the transfer. It was also equipped with a camera to view the cages in the back.

Bioqual’s veterinarian said he confirmed the health of the six chimps before sedating them and moving them to the truck on a cart. Then, he made sure all six chimps were “up” — awake after sedation — before the truck left.

“There’s been tears in the past week, make no mistake,” the veterinarian said of the recent departures.

Landon jokes that after the last of the chimps leaves, he’ll turn the 26 glass-and-steel enclosures into offices. “No one has taken me up on it,” he said of his 140 workers.

Instead, the staff will scrape the colorful, marker-drawn “Tiffany” and “Torian” name tags off the plate glass. Then, Landon said, “I’ll probably dismantle it.”

The Bioqual chimps, meanwhile, will join some 350 others of their kind at the much larger Louisiana lab. There, some chimpanzees are kept indoors, in enclosures similar to Bioqual’s. But others get to roam outside, under geodesic domes, in groups, with fresh air to breathe and trees to climb.