Pets that are microchipped have a better chance of being returned to their owner after entering an animal shelter than those that are not, according to a recent study by Linda Lord, DVM, Ph.D., assistant professor in the College of Veterinary Medicine at Ohio State and service head for Community Practice, Outreach and Shelter Medicine.
Specifically, the return-to-owner rate for cats was 20 times higher and for dogs 2.5 times higher for microchipped pets than were the rates of return for all stray cats and dogs that had entered the shelter.
“This is the first time there has been good data about the success of shelters finding the owners of pets with microchips,” Dr. Lord said. “We found that shelters did much better than they thought they did at returning animals with microchips to their owners.”
For the study, 53 shelters in 23 states agreed to maintain monthly records about microchipped animals brought to the facilities. Only shelters that automatically conduct scans for microchips on all animals were eligible to participate.
Collectively, there were 7,704 microchipped animals that entered the shelters for the duration of the study: August 2007 to March 2008.
Strays made up slightly more than half of the animals tracked in the study, or 53 percent. About 42 percent of the animals had been surrendered by their owners and were not factored into the return-to-owner rate.
About 87 percent of microchips were detected during a scan when the animals entered the shelter; about 10 percent were detected during a medical evaluation and about 2.5 percent were detected just before the animals were scheduled for euthanasia or at some other time.
“We were able to backtrack this data and determine that 12 percent of microchips would have been missed without multiple scans,” Lord said. “We know from a prior study that there are good scanners on the market that can read all microchip frequencies out there. But like any technology, it’s not 100 percent. Many shelters now scan multiple times.”
In all, owners were found for 72.7 percent of microchipped animals. Among those found, 73.9 percent of the owners wanted the animals back in their homes.
Although the study supports micochipping as a valuable permanent pet identification modality, issues related to registration may undermine its overall potential, according to Lord.
“In the study, the biggest reason owners couldn’t be found was because of an incorrect or disconnected phone number in the registration database,” she said. “The chip is only as good as my ability as a pet owner to keep my information up to date in the registry.”
In the cases in which owners were not found, 35.4 percent was attributed to incorrect or disconnected phone numbers, 24.3 percent was owners’ failure to return phone calls or respond to letters, 9.8 percent was attributed to unregistered microchips and 17.2 percent because microchips were registered in a database that differed from the manufacturer.
Most people who obtain a microchip for their pet register their contact information with the chip’s manufacturer, Lord said. However, a pet owner can also register with another company. In addition, many animal shelters keep their own microchip registry databases.
In response to the multiple registration options, the American Animal Hospital Association recently launched its AAHA Universal Pet Microchip Lookup Tool, which performs a real-time lookup of a microchip number and determines which company has a registry for that microchip.
“The site will tell users that a microchip is registered with a specific database and list the registry number to call,” Lord said. “And then you know you’ve got a hit. This is an important development because it’s an easy-to-access, single place to find out where microchips are registered.”
Still, veterinarians can further help in the recovery process by telling clients about the importance of registration, according to Lord.
“We really need to focus on not separating the microchip implantation process from registration,” she said. “Veterinarians have a great opportunity at an annual wellness exam to scan a microchip and remind the owner of the need to keep information up to date in the registry. Likewise, when shelters implant microchips, they need to tell an adopter how it works and make sure information is in the registry before the animal leaves the building.”
Lord also noted that no animal identification is more effective than a tag on a collar that includes the pet’s name and the owner’s phone number.
Lord conducted the study with co-authors Walter Ingwersen, DVM, DVSc, Dipl. ACVIM, of Boehringer Ingelheim Canada’s Vetmedica Division; Janet Gray, DVM, a veterinarian in Redmond, Wash.; and David Wintz of the Larimer Humane Society in Fort Collins, Colo.
Dr. Ingwersen is a consultant for PetHealth Inc., the parent company of 24PetWatch, which offers a microchip program throughout North America.
Lord has also been a sponsored speaker at veterinary meetings by Bayer Animal Health, which offers the microchip system resQ, and Intervet Schering-Plough Inc., which heads the microchip identification and recovery HomeAgain.
The study was published in the July 15, 2009 issue of the Journal of the American Veterinary Medical Association. <HOME>