Seems like a no brainer to me:

http://www.agcenter.com/Documents%20links%20and%20slide%20shows/The%20Case%20for%20National%20ID%20for%20Cattle.htm

With the many problems existing in the livestock business, many producers find designing and implementing an ID program for the national herd something that falls well down the priority lists. The U.S has fallen behind Canada, Mexico, Australia, New Zealand, and most of South America in the required identification of their national herds. The U.S. sells less beef globally because it lacks a national ID program. Inaction on our part of the domestic cattle industry costs U.S. producers hundreds of millions of dollars annually of improved pricing to our national cattle herd and improved production efficiencies at all levels crossing all sectors.

Identifying the animals in the nation's herd with an internationally recognized number hosted in an national database is the beginning and the foundation for resolving the obstacles preventing the world’s recognition of our proper place as the world’s leading producer of quality beef. The rationale for animal identification is unassailable