(KXAN) - Six beagles that have spent their entire lives in cages for laboratory research took their first steps of freedom on Tuesday.

For these dogs, the ground has never felt so good, and the air has never been this crisp.

"They've never touched grass, they've never seen the sun," said Monica Holmes. "They've never known a human that hasn't done something painful to them."

Holmes traveled to Hutto, Texas from Fort Worth to foster one of the dogs.

Beagle Freedom Project, a national non-profit rescue organization, has saved more than 250 former "research beagles" and other animals from laboratories across the country. In the United States, animal testing is legal. Once labs are done with the testing, they typically euthanize the animals.

"They are the industries' dirty little secret, people don't know that dogs are being tested on for their products," founder and president of the organization Shannon Keith said.

Keith says that 96 percent of dogs used in lab testing are beagles because they are docile and don’t tend to bite. Often they’re de-barked so they don’t bother technicians.

Angela Palmer learned about the Beagle Project and adopted a dog last year.

“He has nightmares almost every day and I think, ‘What are you having a nightmare about?’” said Palmer. “Probably something pretty horrible.”

Many household products you may be using have been tested on these dogs.

Some of them include: laundry detergent, dish soap, toothpaste, make-up and pharmaceuticals

The Beagle Project has created an app to help you determine the animal-testing status of a product, available now for iPhones and soon on Android.

Read more at KXAN’s website.