Nestle Purina PetCare Co.’s Waggin’ Train and Canyon Creek Ranch jerky treats or tenders, and the Del Monte Corp.’s Milo’s Kitchen Home-style Dog Treats were the brand names most often cited by pet owners and veterinarians in complaints to the U.S. Food and Drug Administration about illnesses possibly linked to dog treats made from chicken, according to a report Tuesday by said those brands were implicated in an FDA report obtained through a public records request.

The FDA had declined to identify specific brands, saying repeated tests have shown no definitive link to any brand or manufacturer. Nestle Purina and Del Monte have said their treats are safe. There have been no recalls.

Since pet owners first raised the issue in September 2007, the FDA says it has run numerous chemical and microbial tests on Chinese chicken jerky samples but found nothing conclusive to link the treats to a growing number of problems in dogs, including kidney failure, liver disease and Fanconi syndrome.

In November last year, the FDA issued a warning, saying pet owners should be aware that chicken jerky products from China could be associated with reports of Fanconi-like syndrome in dogs, and to watch for signs of decreased appetite, vomiting, diarrhea, increased water consumption and urination in dogs that had eaten jerky products.

Last week, FDA spokesperson confirmed to Food Safety News that the agency has recently received more than 600 reports from dog owners who say their pets have fallen ill or died after eating jerky treats.

Thousands of pet owners have now organized on the Internet asking the government to force a recall of chicken jerky dog treats manufactured from Chinese chicken. 

After receiving pressure from U.S. Sen. Sherrod Brown (D-Ohio) and U.S. Rep. Dennis Kucinich (D-Ohio), the FDA agreed to inspect four Chinese facilities along the chicken jerky supply chain and expedite further tests in an effort to discover the cause of the illnesses.