As of Jan. 22, 2002, hogs within a single production system can move interstate without individual identification, according to the U.S. Department of Agriculture (USDA).

Participants must sign an agreement with USDA's Animal and Plant Health Inspection Service (APHIS) and affected state governments.

The advent of multi-site production systems means animals often cross state lines without changing ownership.

Hogs must test free of communicable diseases to participate in the new program.

Contact APHIS senior staff veterinarian Arnold Taft for details, (301) 734-4916, or log on the APHIS Web site,