Forty male beagles raised inside a laboratory in Spain have been freed from captivity for the first time.
It was the first time the beagles saw the sun and walked on grass.
The dogs arrived in Los Angeles on November 23, where they will be put up for adoption after being released from captivity by the Beagle Freedom Project.
The rescue mission was the largest yet for the group Animal Rescue Media Education (ARME). A total of 72 dogs were rescued in the endeavour, 32 of them having already been adopted in Europe, according to a report by NBC Los Angeles.
During Thanksgiving weekend, volunteers in North Hollywood commenced nursing the remaining 40 dogs back to good health.
The beagles were all between the ages of four and seven and had lived in cages their entire lives, said ARME spokesperson Gary Smith.
"We've been told they lived one per cage in rooms of 10 beagles, but they never had any physical interaction with one another," Smith told the NBC. "They've been in kennels since they were rescued about a week ago, but aside from that, they've spent most of their lives locked up."
According to the Beagle Freedom Project's website, beagles are the breed of choice for lab testing of pharmaceutical, household, and cosmetic products due to their "friendly, docile, trusting, forgiving, people-pleasing personalities, their ability to adapt to life in a cage and the fact that they are relatively inexpensive to feed."
When the beagles are no longer require for research, some labs contact organisations such as ARME who then work to find homes for the dogs.
In June 2011, the organisation gave nine lab beagles a second chance at life and filmed their first steps out of their cages.
ARME is a non-profit advocacy group funded by tax-deductible donations. To find out how to make a donation or adopt a beagle, visit the organisation's website for further information.
"To be able to give these dogs a chance at life after living a life so horrendous none of us can imagine, its perfect timing to think gratitude," Smith told the NBC.
To see the beagles released from captivity for the first time, view the video below.