Fort Lauderdale, Fla. ? Federal regulators said Friday they are investigating potential contaminants in dog treats made in China as the nation’s leading veterinarian association posted a warning to pet owners that the products might be making animals sick.

The American Veterinary Medical Association, which represents 75,000 vets, issued the statement prompted by members’ reports of numerous unusual cases of dogs suffering from a rare kidney ailment after consuming the treats. Most of the products were chicken flavored.

“We want people to know what we are hearing, to pay attention and to monitor their pet’s health,” said association spokesman Michael San Filippo. “We can’t stay quiet, putting our fingers in our ears and ignoring the situation.”

While the association stopped short of advising pet owners not to buy Chinese-made dog treats, San Filippo said: “I would be leery, especially if it was something I had not given my pet before.”

Food and Drug Administration spokesman Mike Herndon said the agency is trying to determine whether the jerky treats pose a threat, but has not singled out individual brands or requested any recalls. Several veterinarians said they first reported their cases to the FDA about three weeks ago.

Investigators advised pet owners not to panic. Initial tests of the most likely toxic ingredients – including melamine, a component in plastics that was behind the massive Menu Foods recall earlier this year – have come back negative, “and we are continuing to investigate,” Herndon said.

Dr. Richard Goldstein, associate professor of veterinary medicine at Cornell University and part of the team assisting the FDA in its investigation, said most of the affected dogs are small breeds that had developed renal problems. Symptoms include vomiting, lethargy and lack of appetite.