Little Rock, AR – Tyson Foods is asking federal officials to help control potential economic damage after mad cow disease was discovered in a cow in Washington state. Tyson is one of the world's largest beef producers. Even though the cow was not in Tyson's system, the company is reporting a drop in its share prices. Several nations already have banned U-S beef imports, and a Tyson spokesperson says it's still too early to know how much the company's export business will be damaged. In last year's annual report, Tyson's overseas beef sales amounted to one-point-four billion dollars. The company operates five processing plants in north Alabama.