The agency has spent years trying to find out why 3,600 dogs and 10 cats in the U.S. were sickened by different brands of the treats since the agency first started getting complaints in 2007.
Of the thousands affected, approximately 580 animals died.
"This is one of the most elusive and mysterious outbreaks we've encountered," FDA Center for Veterinary Medicine Director Bernadette Dunham said.
Some pets developed symptoms after ingesting the jerky treats and the severe cases included kidney failure, gastrointestinal bleeding, and a rare kidney disorder.
The agency has conducted more than 1,200 tests including checks for Salmonella, metals, pesticides and other poisonous compounds in different brands of the treats but has been unable to decipher what is causing the infection.
The FDA is asking that anyone who suspects their pet may have gotten sick after eating tainted jerky to contact the agency immediately.
