(Wilmington, Delaware-AP) -- Agriculture officials in Delaware and Maryland have issued emergency orders prohibiting farmers from cleaning out chicken houses in an effort to prevent the spread of avian influenza.

The emergency orders forbid any clean-out, movement, transportation, or field application of poultry litter on farms in Delaware and most of Maryland's Eastern Shore until at least March 10.

Delaware's order also prohibits the transportation of live poultry within the state or across state lines. But it includes an exemption for the four large poultry companies with integrated operations on the Delmarva peninsula.

In Maryland, transportation of live poultry within the restricted area is prohibited unless the flock has tested negative for avian influenza and the state's agriculture secretary has given permission.

(Copyright 2004 by The Associated Press. All Rights Reserved.)