WASHINGTON — Initiating a mandatory national animal identification system is supported by the U.S. pork industry, said David Kempen, a Poteet, Texas pork producer, during a U.S. Department of Agriculture listening session held recently in Austin.

Mr. Kempen, who presented comments on behalf of the National Pork Producers Council and the Texas Pork Producers Association, told U.S.D.A. officials, "Until animal identification is made mandatory and all premises are registered, it will never have the intended effects of improving the animal-health infrastructure, aiding in the control and eradication of highly contagious foreign and domestic animal diseases and, ultimately, protecting the U.S. livestock industry, its producers, processors and hundreds of related businesses and more than a half-million mostly rural jobs for Americans."

Concerns issued by critics of U.S.D.A.’s National Animal Identification System were addressed by Mr. Kempen, including cost, privacy, liability and logistics.

In 1988 the U.S. pork industry established a swine I.D. system, which helped eradicate pseudorabies from the commercial herd. Industry has since enhanced its system and made it consistent with the N.A.I.S. by registering swine premises and asking pork packers to require premises registration as a condition of sale.

More than 54,000, or 80%, of the estimated 67,300 hog farms have been registered by the N.P.P.C. and the National Pork Board. Premises-registration data includes the physical location of a farm, a contact telephone number and other publicly available information.