By Steve Bittenbender

LOUISVILLE, Ky. (Reuters) - A male monkey captured earlier this week in eastern Kentucky, remained in quarantine Thursday but how the adult Rhesus made it to the region is unknown, his current caretaker said.

April Truitt, executive director of the Primate Rescue Center, received a call late Tuesday from someone in Bath County, about 45 miles east of Lexington, who reported spotting the monkey near their home. Truitt then called Kentucky Fish and Wildlife officials.

Less than 12 hours later, officials tranquilized the monkey and brought it to Truitt’s facility near Nicholasville. Truitt said the monkey was found close to the location of the caller’s home, indicating it was probably being fed by someone in the area.

"He was not in good health," she said.

Truitt noticed the monkey had a chest tattoo, which is typical for laboratory animals, but believes that somehow the monkey became a pet. The monkey’s tattoo indicates he was born in August 2005, which is when Kentucky banned owning a monkey as a pet.

Because of the attention the case has received, Truitt does not believe the people who lost the monkey will come forward.

"That should never have happened,” she said, regarding his departure from a lab.

The monkey came to Truitt weighing 9.7 pounds, which is less than half the weight of an adult male, she said. However, Rhesus monkeys are considered a hardy breed.

While in quarantine, Truitt said she is feeding the monkey peanut butter sandwiches to help it gain weight, and she hopes it will feel better within a week.

Located on 40 acres about 15 miles southwest of Lexington, the rescue center is home to 11 chimpanzees and about 40 monkeys. It is one of eight sanctuaries belonging to the North American Primate Sanctuary Alliance, which cares for about 600 animals in the U.S. and Canada.

(Reporting by Steve Bittenbender; Editing by Ben Klayman and Bill Trott)