When the topic of microchipping comes up, it is always accompanied by numerous questions: Is microchipping more effective than a tattoo? How much does it cost? Which microchip should I chose for my Boxer? Is one chip better than another?

Peggy Sorensen, D.V.M. in Phoenix, Arizona (VCA Northern Animal Hospital), authored an article published in the "Journal of the American Veterinary Medicine Association" - a retrospective study of microchipping. She graciously consented to share her knowledge - and opinions - with the Boxer Mailing List.

HOW DOES A CHIP WORK?

The chip is an antenna - there is no battery. The scanners used to detect a chip use radio waves. Each chip has an identification number which is registered with the microchip company registry. If a Boxer, for example, was scanned at a shelter and found to have a chip, the number would then be traced to the dog's owner.

HOW IS A CHIP IMPLANTED?

The chip itself is about the size of a grain of wild rice. It is implanted with a 12-guage needle and should be placed in the muscle or fat between the shoulder blades. Dr. Sorensen says the newer chip technology is extremely effective in preventing migration of the chip "if the chip is implanted properly." She implants at a 45-degree angle and buries the needle, making sure the chip is lodged in the muscle or fat, not the sub-Q space. She puts it like this: "Think of what happens when you inject subcutaneous fluids - the fluids move down. The same will happen with a chip if it isn't implanted properly." Dr. Sorensen has found only a few chips that migrated and they were the older chips - chips without a protective coating or cap.

According to Dr. Sorensen, most animals react very little to the implant procedure - in fact, she says most - in her experience -- react more to vaccinations than microchipping.

CHIPS ON THE MARKET

Today, there are two major chips being implanted in the United States: AVID and Home Again. There are some differences between the two, but Dr. Sorensen is quick to say, "Both of these chips are good. The companies are competing against each other, but they are also trying to work together because we all have the same goal: reuniting people and their animals."

AVID

* Manufactured and marketed by the same company; sells to vets and vets can act as reps for the company * Features total tracking of their chips so a chip can be located even before it is implanted * Chips are coated with the same material used to coat pacemakers; prevents migration if implanted properly * Stands behind chips implanted in exotics such as ferrets, rabbits, snakes, birds * Offers a multi-animal discount fee (can register 8 animals for a $40 fee) * Scanner will read the numbers of all chips * Chip numbers are numbers only

Home Again

* Marketed by a large pharmaceutical company * Does not track chips until one is registered after implantation * Chips feature an anti-migration cap; effective in preventing migration if implanted properly * Stands behind chips implanted in dogs and cats only * Fee for chip registration is not discounted for multiple animals * Scanner will signal the presence of a chip and identify the kind of chip - will read the number for Home Again chips only * Chip numbers are alphanumeric

Based on her experience and research, Dr. Sorensen prefers the AVID chip. She says, "In my personal opinion, there are simply more positives to AVID." She particularly likes the tracking system which can help locate an owner through the vet or vet clinic - perhaps even before the number registration has been received. She also likes the fact that AVID stands behind chips implanted in exotics.

Should you worry if you have a different kind of chip? According to Dr. Sorensen, if you have your Boxer chipped with Home Again, he or she will be found because Home Again is a good chip and the number can be read by an Avid scanner.

Dr. Sorensen says AVID is more widely used. In Arizona, for example, 85% of the vet hospitals have AVID scanners and so do all the shelters. Home Again has made scanners available to shelters at no cost, but they still aren't as prevalent. Some shelters are using "universal scanners."

AVID is active in countries outside the United States and the registry goes beyond U.S. borders as well. Dr. Sorensen does not know the status of Home Again in countries other than the U.S.

Dr. Sorensen notes there is another brand of chip which amounts to less than 1% of the market. The InfoPet chip can be read by a universal scanner or an InfoPet scanner.

SHOULD YOU GET YOUR BOXER MICROCHIPPED?

Dr. Sorensen is a firm believer in the effectiveness of chipping, and says there's a much better chance you will be reunited with your Boxer if he or she has the chip. Many people tattoo their dogs, but tattoos fade - and what good is a tattoo if it isn't listed in a national registry?

TIPS FROM DR. SORENSEN

* Make sure the chip is scanned before it is implanted in your Boxer. * Make sure the dog is scanned immediately after implantation to make sure it is working. * When you visit your veterinarian, ASK that the chip be scanned to make sure it is working and has not migrated. * If you have your Boxer at a dog show or event that features microchipping, ask to have your dog scanned to provide yet another check of the chip.

Author's note: Dr. Sorensen estimates she has chipped over 400 animals including dogs, cats, horses, cattle, snakes, birds, ferrets, rabbits, and an iguana. She clearly stated a bias in favor of the AVID chip prior to the interview - and she says she is a rep for AVID. At this time, however, she is not an active rep because, as she put it, "My veterinary practice comes first." Dr. Sorensen feels it is important for you to have this information so you can form your own opinions about the different chips that are available - and microchipping in general.

COMMENTS FROM A SHELTER SUPERVISOR

Debbie Nichols is a kennel supervisor at the Maricopa County Animal Control Shelters in the Phoenix area. She wishes more pet owners would chip their animals.

According to Ms. Nichols, the shelters she oversees take in 60 to 160 animals a day in the busy season (cats and dogs). From November through March, the number goes down to 30 to 80 animals per day. Most are strays. "Very few dogs are microchipped," says Ms. Nichols. In fact, she says it is rare to find a chipped pet. All animals brought to the Maricopa County Animal Control Shelters are scanned when they first arrive; they are scanned again just prior to being euthanized.

These shelters have AVID, Home Again, and InfoPet scanners. Of the dogs that were chipped, most had AVID chips.

Several times a year, Rabies/Animal Control conducts clinics for vaccination, neutering, and microchipping - at a minimal cost. Ms. Nichols says she is always disappointed at the turnout.

"We could save so many dogs from death if only their owners had gotten them chipped."

Copyright 1997 Maryann Watkins and the Boxer Mailing List