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Understanding Your Pet’s Microchip

August 13, 2016
by Ellen F. Houser

Despite a caregiver’s best intentions, sometimes a dog or cat will get outside by accident. This can be as frightening for the pet as it is for the owner. The American Humane Association (AHA) recommends that pets wear collars with tags that include the owner’s name, address, and telephone number, along with the pet’s name. The Association suggests that even indoor-only cats be tagged because they could slip through an open door and become lost. A safety collar with a short piece of elastic sewn into it will allow a cat to escape if it gets caught on window blinds, furniture, fencing, or other objects ( Seeing a cat outside that is wearing a collar helps to make people aware that it is owned and possibly lost, not stray or feral.

If you have adopted a dog or cat from PAWS, your pet has a HomeAgain Microchip Implant that includes services such as 24/7 Emergency Medical Hotline Care, Found Pet Travel Assistance, and Lost Pet Posters. The microchip provides permanent ID that cannot fall off, be removed, or become impossible to read ( If your pet does not have a microchip, you can have one implanted at a veterinarian’s office for about $50 (

How microchips work

According to the American Medical Veterinary Association (AMVA), “a microchip is a small, electronic chip enclosed in a glass cylinder that is about the size of a grain of rice” ( It is injected using a hypodermic needle under the loose skin between the shoulder blades ( No anesthesia is needed, as it is no more painful than other types of injections. The chip itself contains identification numbers, and passing a hand-held scanner over the microchip transmits the numbers to the scanner’s display. The chip uses radio frequency identification, which does not require a battery and will not wear out. Note, however, that a pet’s microchip does not contain a tracking device and cannot be used to determine the location of an animal (

Benefits of microchipping

Most shelters and veterinary clinics have microchip scanners, and when an apparently lost pet is found and taken to such a facility, the animal will be scanned for a microchip. If one is found and if the microchip registry information is up-to-date, the pet and its caregiver can be reunited.

Dog behind fence and sorrowful cat The AHA estimates that over 10 million dogs and cats are lost or stolen each year in the United States. A study published in the Journal of the American Veterinary Medical Association underscored the importance of microchip registration with the following statistics:

For dogs

  • Only about 22% of lost dogs entering animal shelters were reunited with their families.
  • The return-to-owner rate for microchipped dogs was over 52% or nearly 2.5 times better than for non-microchipped canines.

For cats

  • Less than 2% of lost cats entering animal shelters were reunited with their families.
  • The return-to-owner rate for microchipped cats was dramatically higher at over 38%, nearly 20 times better than for non-microchipped felines (

“In all, owners were found for 72.7% of microchipped animals” (

Pet owner responsibilities

The study cited above also found that only 58% of the microchipped animals’ chips were registered with the pet owner’s current contact information. Having an animal microchipped is just the first step. In addition, every caregiver should:

Create an account with the microchip manufacturer,

Enter key information such as the owner’s name, address, and telephone number(s),

Update information with the registry each time his/her address or phone number changes (, and

Ask the veterinarian to scan the pet’s microchip at each yearly check-up to make sure the microchip is still functioning and can be detected (

The AMVA and the American Animal Hospital Association have designated August 15 as “Check the Chip Day” to remind pet caregivers to keep registration data current. You can increase the likelihood that a lost pet will be returned to you by using a collar and tags, even for indoor-only pets, as well as by making sure that the contact information associated with your pet’s microchip is up to date.