One of North America's largest pet-food suppliers said Friday it'srecallingsome of the premium dog and cat food it sells through stores such as Wal-Mart and Safeway at a cost of up to $40 million after several animal deaths in the United States.

Menu Foods based in Streetsville, west of Toronto, called the recall of its products sold in cans and pouches precautionary.

CEO Paul Henderson told the Canadian Press that exhaustive tests by both internal and external specialists had failed to identify the problem.

"We're not entirely sure what has happened," Henderson said. "We've undertaken a battery of technical tests… and all of those tests have failed to identify any issues at all with our product."

Only U.S. pets affected

One dog and a "small number" of cats in the U.S. are reported to have died from kidney failure after eating the food, Henderson said.

There had been no complaints from Canadian pet owners.

The company said it had also beefed up the testing of all raw materials and finished goods.

Menu Foods, one of the leading North American private-label and contract manufacturer of wet pet-food products, produced more than one billion containers last year.

It supplies its products to 17 of the top 20 retailers in North America for sale under store labels such as Master Choice, Compliments and Select, and it manufactures for several national brands.

Starting in December, concerns began filtering back to the company through toll-free customer lines about its "cuts and gravy"-style pet food.

Callers complained their animals had fallen ill although no direct link to the food was established.

Menu Foodshas posted a list of productsaffected by the recall on its website.

The company said itdiscovered that "timing of the production associated with these complaints coincides with the introduction of an ingredient from a new supplier." It says it stopped using this ingredient shortly after this discovery.

The recall affects products made between Dec. 3, 2006, and March 6 at two of its American facilities in Emporia, Kan., and Pennsauken, N.J.

Menu's other plants are in North Sioux City, S.D., and Streetsville.

The Menu Foods customer service hotline can be reached at 866-463-6738for more information on what brands were affected.