A group that represents about two-thirds of Ontario's veterinarians has invited its members to report incidents they think may be related to poisoned pet food.

At least 16 pet deaths and as many as 104 resulting from kidney failure have been reported in North America among animals that ate tainted food produced by Menu Foods of Streetsville, Ont.

The Ontario Veterinary Medical Association on Wednesday invited its 2,300 members — out of about 3,300 vets in the province — to report any cases that they had seen.

"We pretty well left it up to them" what they chose to report, said Nadia Vercillo, manager of communications and public relations. "It's just a really informal survey of our members."

The group took the step because its members were concerned about the food, she said. "Veterinarians are as upset as the pet owners out there."

The association may publish the results, but does not expect to have any data before next week at the earliest, she said.

The group does not want to hear from pet owners, only from vets, because they have the expertise to analyze what is wrong with an animal.

Menu Foods on Tuesday confirmed 16 deaths. The U.S. Veterinary Information Network reported 104 the same day, and it had been told about 471 cases of kidney failure by its members, including vets, students and people in the pet industry.

U.S. agriculture officials confirmed Friday that some Menu Foods products contained traces of aminopterin, a type of rat poison.

Menu Foods issued a North America-wide recalls of 95 brands of "cuts and gravy" style cat and dog food after reports of animal deaths and illness.

The recalls involve food manufactured between Dec. 3, 2006, and March 6, 2007.