Members of a veterinarians' Web site reported at least 471 cases of kidney failure among pets in the 10 days since a nationwide pet food recall and the founder of the site said the total could be in the thousands.
Paul Pion, the founder of the Veterinary Information Network, a Web site of 30,000 veterinarians and veterinary students, said Tuesday the number of reported cases had already grown higher than the 471, but he wouldn't have an updated tally for a few days.
Of the 471 cases reported, 104 animals died, 59 survived and the rest were still undergoing treatment, Pion said. The survey results were earlier reported by the Los Angeles Times.
Pion, a California veterinarian, said only 10 percent to 20 percent of his Web site's members had responded to a request for information.
"We are trying to do a more widespread survey in a more structured way," he said.
A spokesman for Menu Foods did not immediately return a call for comment.
Rat poison identified
Scientists at the New York State Food Laboratory last week identified the rodent poison aminopterin as the likely culprit in the scare that prompted the recall of 95 brands of "cuts and gravy" style dog and cat food by Menu Foods of Ontario, Canada.
Some pets that ate the recalled brands suffered kidney failure, and the company has confirmed the deaths of 15 cats and one dog. Aminopterin, a derivative of folic acid that was once used to induce abortions and is now banned as a rodent poison in the United States, can cause kidney damage in dogs and cats.
"I'm sure we haven't seen half the cases and if you double what we've seen, it's a thousand," Pion told The Associated Press Tuesday. "If we're only getting 10 percent of the veterinarians, you can do the math."
"The bottom line is, it's much more than 16," Pion said.
Veterinary Information Network provides a secure site where veterinarians share clinical information and other resources such as conference schedules and continuing education courses.
More attempts to pinpoint tainted ingredient
Researchers at the New York food lab, Cornell University and other labs continued Tuesday to try to pinpoint which individual ingredients were tainted with the poison, officials said. They also said there could still be undetected hazards in the food.
The U.S. Food and Drug Administration has said the investigation into the pet deaths was focused on wheat gluten.
Testing has not been easy.
Wheat gluten has "been a real difficult sample to work with," Daniel Rice, director of the state food lab, said. "It's real sticky, gummy. If you can imagine wet flour and you're trying to get that into solution and put that into an instrument."
Scientists so far have offered no theories on how aminopterin got into the products of Menu Foods, which makes pet food for most of North America's top retailers.
The company on March 16 recalled products packaged from Dec. 3 to March 6 and advised retailers last week to remove all the products from their shelves to verify the dates they were packaged. Products not made between those dates can still be sold.
The recall covered products carrying names of major brands including Iams, Nutro and Eukanuba. The food was distributed throughout the United States, Canada and Mexico by major retailers such as Wal-Mart, Kroger and Safeway.