Microchips give animals identity

PHILADELPHIA — Each day, Patrick McCallion takes his 13-month-old dog Stewart to the corner park, where the exuberant yellow Lab mix can run loose with his pooch pals. But the park isn't enclosed.

So McCallion took out a bit of disappearance insurance, getting a microchip the size of a grain of rice implanted under the dog's skin, between the shoulder blades.

In the last few years, millions of dogs and cats — as well as tigers and other unusual pets — have been implanted with these microchips, which are encoded with unique numbers to make identifying lost, stolen or abandoned animals a snap.

When a lost pet is brought to a shelter or clinic, workers can use a hand-held scanner to read the chip's number. A computer database then matches the number with the pet's owner, medical history and other pertinent information.

At Queen Village Animal Clinic, where Stewart got his chip, the injection costs about $30, plus a one-time registration fee of $12.

"Probably every day at least one dog runs away from that park," said McCallion, 28, of Philadelphia. "You always see the 'missing' posters on trees and poles around the city."

The chips have been used to reunite thousands of lost pets with their owners. In northeastern Pennsylvania, LeeAnn Perry's dog, a yellow Lab named Sara, has run away three times since getting the chip a year-and-a-half ago.

The pooch last disappeared in November, but was back home two weeks later.

"I know when she takes off, one way or another she'll be back because she's chipped," said Perry, 32, of Dunmore, Pa.

Microchip implantation has been around since the 1980s but was relatively rare until the mid-1990s, when chipmakers introduced a universal scanner that could read every model.

Scanners are now found in most shelters and animal control agencies across the country, according to Mary Madsen, a customer service supervisor for AVID Identification Systems Inc.

Norco, Calif.-based AVID is one of two dominant chipmakers. As of last year, 2.5 million pets were listed in the company database.

The American Kennel Club operates the other database, which contains more than 1.1 million pets and is affiliated with Schering-Plough Animal Health, distributor of the HomeAgain chip.