OTTAWA - The Canadian government has confirmed a new case of mad cow disease. 

The Canadian Food Inspection Agency said Tuesday the brain wasting disease showed up in an Alberta cow under seven years old. 

Officials say no part of the animal has entered the human or animal feed system. Agency officials were to hold a news conference Tuesday afternoon to discuss the new case, the second case of bovine spongiform encephalopathy found in Canada this year. 

The age of the cow means it was born after a 1997 feed ban in Canada removed the use of ruminants in feed, commonly believed to be the cause of the disease. That could make the cause much more difficult to trace. 

The new case comes as the U.S. Department of Agriculture showed signs it is looking to withdraw its plan to allow imports of young live cattle from Canada. 

The trade ban has depressed Canadian prices and crippled ranches and feedlots. Cattle farmers have lost an estimated C$5 billion ($4.1 billion) since the first home-grown case was found in May 2003. 

The USDA had announced plans to restart trade on March 7, after it learned about Canada's second case of the disease, which was confirmed on Jan. 2. 

U.S. cattle farmers have said in recent days they thought the plan should be delayed. 

A U.S. industry source said the USDA's Animal and Plant Health Inspection Service was reconsidering the move on Tuesday. 

"Career folks at APHIS are saying they are going to kill the rule," the industry source said. 

A USDA spokesman declined comment.