Cattle older than 30 months soon may be rolling back across the border. Bush administration officials said they plan to lift the remaining trade restrictions on Canadian cattle, including older cattle and breeding stock. A notice was to be published in the Jan. 8 Federal Register.

The United States first closed the border to all Canadian cattle for two years when an Alberta cow was diagnosed with bovine spongiform encephalopathy, commonly known as “mad cow disease,” in May 2003. The United States then lifted the ban in July 2005 for animals younger than 30 months after winning a court battle with American protectionist groups.

Since then, subsequent mad cow cases in Alberta, British Columbia and Manitoba, as well as ongoing disputes with groups such as R-CALF USA — which says older cattle present a greater risk of mad cow — have delayed the U.S. Department of Agriculture lifting the remaining import restrictions.

Canadian cattle farmers, feedlots and livestock trucking companies have suffered for the past three years as the herd north of the border has swelled, although the number has been falling slowly since the ban was relaxed in 2005.

The U.S. imports about 12 percent of its beef; in 2005, Canada accounted for nearly a quarter of those imports.

The USDA plan will go through 60 days of public comment ending March 1.