WASHINGTON – A U.S. company asked customers Monday to return dog food that may have come from a Canadian cow that tested positive for mad cow disease, the Food and Drug Administration said.

Pet Pantry International, of Carson City, Nev., said customers should search for two products: “Maintenance Diet” with a “use by” date of “17FEB04” and “Beef with Barley” with a date of “05MAR04.”

If found, the food should be held for pickup. The company’s products are purchased by phone or e-mail and delivered by franchises to consumers’ homes.

There is no known risk to dogs and no evidence that dogs could transmit the disease to humans, the FDA said. The voluntary return is a precaution to prevent discarded dog food from getting mixed with feed for cattle, goats or sheep.

Customers who purchased dog food since February should check their supplies and, if found, should call the company at 1-800-381-7387. Pet Pantry is using sales records to contact consumers.

The suspect food, in 50-pound bags, was produced in Canada by Champion Pet Food of Morinville, Alberta.

The Canadian government already has prevented meat from the single diseased cow to be processed for human food.

Test results have cleared all other cattle in the original herd linked to North America’s first mad cow case in a decade, Canadian officials said Sunday.