PORTLAND (AP) - Oregon veterinarians say they suspect 13 pets have died among 47 sickened after eating tainted food.

“The more people know about it, the more we're going to hear about new cases,” said Emilio DeBess, Oregon's public health veterinarian. “This may grow a little bit more as time goes on.”

Oregon's toll has grown as veterinarians statewide have examined their records.

The latest figures include 31 cats and 15 dogs. DeBess is waiting to learn the species of the 47th. The fatalities consist of seven cats and six dogs.

DeBess said the 47 cases include animals of varying breeds from all over the state, ranging in age from 6 months to 17 years. Most of the dogs were younger - the oldest was 12 - while most of the cats were older than 10, DeBess said.

Cats tend to be susceptible to kidney disease as they age, while dogs typically develop other health problems. “Kidney disease is very low on their list,” DeBess said.

New York scientists have identified aminopterin, used as a rodent poison in some countries, as the likely culprit of disease that prompted the recall of 95 brands of “cuts and gravy” style dog and cat food.

Scientists so far have offered no theories on how the poison got into the products of Menu Foods, which makes pet food for most of North America's top retailers.