Know Your Microchips
Pet parents know there are several ways to help a wayward animal get returned home. The most popular are collars with ID tags and microchipping. If I were a gambler, I'd bet on the use of both. Collars with the vital ID tag attached can slip off or wear off. All brands of microchips are not yet able to be scanned by all available scanners. The following article from Cats Walk, Volume 5, No. 04 - May, 2007, should be read by those who have chosen microchips for their pets.
by Dr. Jean Hofve & Jackson Galaxy
Bayer Animal Health introduced a new microchip and scanner called resQ Pet Tracking System. The new chip is ISO (International Organization for Standardization) compliant and features a no-cost pet registration database. The microchips by Avid and HomeAgain, which have been around for many years, are much more common in pets and shelters usually have the scanners for them, though they are not in compliance with ISO. Banfield, The Pet Hospital created a huge stir when it introduced its ISO-compliant chip, because shelters didn't have scanners for it, and several pets with Banfield chips are known to have been euthanized as strays after standard scanners failed to recognize the chip. Bayer is Banfield's partner.
The advantage to the ISO-compliant chip is that it can be recognized in Europe. Isn't that nice for our globetrotting pets? Bayer and Banfield plan to donate 20,000 scanners to shelters. But animals carrying the still-uncommon Bayer chips may still go undetected in the US. In the shelters that do have both, will they will keep both scanners handy, and train their staff and volunteers on how to use both systems? And how many harried shelter employees and volunteers will remember to use both scanners - even if they can find both of them at the same time - on every animal?
Thumbs down to Bayer and Banfield for 1. trying to force their chips into the market, attempting to bankrupt the other two companies who pioneered the use of microchips and who donated scanners to many more shelters, 2. ignoring the massive database kept by AKC of the other chips, and 3. for giving people a completely false sense of security while happily taking their money, knowing that until those 20,000 scanners are in every shelter in the US and every worker knows how to use them, and does, that pets with the Banfield chips have been for years and still are completely unprotected.
In a different view of the same subject, there has been an interesting warning going around the internet about microchips causing cancer. Here's the deal: in animals, especially cats, any trauma can cause a fibrosarcoma, including injections of any kind (although the risk is much higher with killed adjuvanted vaccines like rabies, feline leukemia, and FIV). The mice in the studies were strains that have a high propensity for tumor formation, so one would expect a much higher reaction rate for those mice than for dogs or cats. In all the years microchips have been used in the US (since I was in vet school!) there have been 2 reports of fibrosarcoma formation around a microchip in a dog (one in the US and one in Italy).
While there is a remote risk of injection-site tumor with any injection including microchips, I still believe that microchipping is a valuable safeguard for your pet, preferably in addition to a well-fitted collar and tag - breakaway collars only for cats! The chances of an indoor cat slipping out or a dog finding a way out of its yard are much higher, and without identification, few pets ever make it home (only about 2% of cats coming in to a shelter are ever reclaimed). Personally, I microchip all of my pets, despite my own cat being the rare one who reacted badly - a sterile abscess from his shoulder to his elbow.
Do ask the (experienced) person inserting the microchip to make sure it is placed just under the skin and not in deeper tissue. One person managed to force the chip straight down between two vertebrae and into the spinal cord of a cat. Not an easy feat! It paralyzed the cat, who recovered after spinal surgery. The chip should be placed well away from the area where a collar would ride, and very slightly off the midline to avoid important acupuncture meridians. And give one dose of homeopathic Ledum 30C by mouth afterward, to prevent reactions.