There are two reasons that this topic might be of interest to you. Either you and your dog travel within the United States and you are concerned about the possibility that your dog will be lost, or you plan to travel abroad and need to microchip your dog to meet the import requirements of certain countries (e.g., the E.U., the U.K., Japan).

Either way, the situation should be simple: you go to the vet, they inject a microchip under the skin at the base of your dog’s neck, and later on someone with a scanner (an animal shelter, a vet’s office, a customs agent) can read her chip and access your contact information. Instead, it turns out to be extremely — and unnecessarily — complicated. Here is a useful Wikipedia entry that provides detailed information about the microchip mess.

First, there are multiple types of chips. The various chips differ in the frequencies they operate on (125kHz, 128 kHz, and 134.2 kHz) and whether or not they’re encrypted. The International Standards Organization (ISO) selected 134.2 kHz as the international standard, and it is indeed the standard for everywhere except the U.S., where the leading chip manufacturers chose to stay with 125 kHz (AVID, with nearly all of the market share, was particularly resistant to adopting the 134.2 kHz standard).

Second, scanners are made that read all four types of chip, but for a long time they were not widely distributed (so you could not be sure that the chip you chose for your dog would be read by the scanner of the particular shelter she found herself in). Bayer/ResQ and HomeAgain are making a new effort to make a “universal” scanner universally available in the U.S., and Dog Jaunt certainly hopes they’ll succeed.

In this interim period, what should you do? Dog Jaunt recommends that (1) if your dog already has a 9-digit, 125 kHz chip and you want to travel abroad, consider adding another, ISO-compliant chip; and (2) if your dog hasn’t been chipped at all and you want to travel abroad, consider where you travel in the U.S., and choose either to double-chip your dog or go with the rapidly-spreading ISO-compliant chip. Here’s why:

The chip that is still most common in the U.S. is 125 kHz, and many shelters (especially those away from metropolitan areas) may still have scanners that read or detect only those chips. The standard chip abroad, however, is 134.2 kHz.

Some on-line guides suggest that if you want to go to France with your dog, she must have a 15-digit, 134.2 kHz chip that is fully-compliant with ISO standard 11784, not one of the chips that were grandfathered in under Annex A ISO standard 11785 (the Annex essentially grandfathered in some established chips to the new standard, including the 10-digit “FECAVA” type of chip — the leading examples are the AVID Euro Chip and HomeAgain’s 10-digit chip). This notion is supported by the fact that the transition period for Annex A microchips ended in 1998; since 1998, technically, only 15-digit, 134.2 kHz chips are “true” ISO standard microchips.

However, the French embassy sent me its policy regarding the private importation of dogs, cats and ferrets, and the relevant portion states that “every animal must be identified by a microchip (standard ISO 11784 or annex A ISO standard 11785).” I confirmed that French customs will accept either a 15-digit ISO standard 11784 chip or a 10-digit FECAVA chip. The 15-digit chip, however, is “the recognized and recommended one,” my embassy contact said.

In fact, France, like many other countries, will allow you to import your pet with a 125 kHz, 9-digit chip, but only if you buy your own scanner and bring it with you so that customs can verify that your dog is implanted with the chip that’s referenced in all your import papers. Dog Jaunt can’t love this idea. First, scanners are expensive ($100-$200) and they’re one more object to keep track of (or lose). Second, if your dog is lost in that country, no one but you will have the scanner that’s needed to read her chip. If she has an ISO-compliant chip, on the other hand, the foreign shelter that finds her will detect that she’s chipped and recover your contact information. If your dog already has a 9-digit chip and you want to travel abroad, it seems like a better idea to buy a $50 ISO-compliant chip for your dog instead of buying a scanner.

Indeed, many people have chosen to double-chip their dogs. The procedure is no more painful for your dog than an injection, and while some concerns have been raised about microchips causing cancer, the risk appears to be negligible. Also, the presence of one chip does not prevent the other from being read. [10/25/10 I spoke recently with a very knowledgeable USDA inspector here in the State of Washington, and he strongly suggested that if you double-chip your dog, be sure that your veterinarian mentions that fact on your dog’s international health certificate, and provides a brief explanation of why that was done, so that a customs officer can refer to that explanation when a scan reveals two chips but can only read one.]

If you want your dog to be chipped with a chip that your particular vet doesn’t carry, you can buy it on-line and bring it to the vet for implantation. Fully-compliant, 15-digit ISO chips are marketed in the U.S. under the brand names ResQ and Datamars (Crystal Tag). The ResQ chip is only available through a vet, but you can buy the Datamars (Crystal Tag) chip from PetTravelStore.com. (Please note that do-it-yourself directions were included in the Datamars (Crystal Tag) chip I bought, but positioning the chip is a bit tricky and is best left to a vet.)

Chloe recently got microchipped, by the way. We chose the fully-ISO-compliant ResQ chip for her, because we typically travel to places in the U.S. where the shelters are likely to have received a universal scanner by now; we plan to visit Europe with her as soon as we have two euros to rub together; and our vet had the ResQ chip in hand (our Datamars chip hadn’t yet arrived).