The U.S. Agriculture Department said on Friday as many as 20 million chickens currently on U.S. farms in several states may have been fed contaminated feed.
A USDA official said the birds must be held until the government can complete a risk assessment to determine if they can be processed. The results could come as early as Monday.
The birds were among those believed to have been given contaminated feed with pet food containing melamine, a chemical used in plastics and fertilizer. It is uncertain how many
chickens have been processed.