PHOENIX -- The FDA is asking for the public's help in solving a mystery that has left them stumped for years.
The agency is looking for pet owners who have fed their dog or cat jerky treats made in China and as a result, their animal has fallen ill or died.
Since 2007, there have been 3,600 cases of illness, resulting in 600 pet deaths.
"We don't know. That's why we are enlisting the help of licensed veterinary practitioners and consumers through a letter we sent out today asking for help or more information," said FDA spokeswoman Shelly Burgess.
According to Burgess, the FDA's Center for Veterinary Medicine has "conducted more than 1,200 tests, visited jerky pet treat manufacturers in China and collaborated with colleagues in academia, industry, state labs and foreign governments, yet the exact cause of the illnesses remains elusive."
The FDA reports that within hours of eating the treats, sold as jerky tenders or strips made of chicken, duck, sweet potatoes and/or dried fruit, some pets have exhibited decreased appetite, decreased activity, vomiting, diarrhea (sometimes with blood or mucus), increased water consumption and/or increased urination. Severe cases have involved kidney failure, gastrointestinal bleeding and a rare kidney disorder.
About 60 percent of cases involved gastrointestinal illness and about 30 percent involved kidney and urinary systems. The remaining cases reported various symptoms, such as collapse, convulsions or skin issues.