Pet Microchipping 

Dr. Vishal Sharma *    

Nowadays pet microchipping is a common practice. Most of us, however, do not know what exactly the microchip is and what it is used for; let alone how to implant them and if there are side effects of this procedure. The following is an overview of pet microchipping.

The Microchip: Microchips are about the size of a large grain of rice and are based on a passive RFID (radio frequency identification) technology. Each microchip has a unique identification number. Microchips are a passive or inert, RFID device, and contain no internal power source. They are designed so that they do not act until acted upon. They only become active and start sending information when a scanner is used. The rest of the time they are totally inactive.

Most microchips comprise three basic elements – a silicon chip (integrated circuit), a coil inductor, or a core of ferrite wrapped in copper wire and a capacitor. The silicon chip contains the identification number plus the electronic circuit to transmit that information to the scanner. The inductor acts as a radio antenna, ready to receive electrical power from the scanner. The capacitor and inductor act as a tuner, forming an LC circuit. The scanner presents an inductive field that excites the coil and charges the capacitor, which in turn energizes and powers the IC. The IC then transmits the data via the coil to the scanner.

These components are encased in a special biocompatible glass made from soda lime, and hermetically sealed to prevent any moisture or fluid from entering the unit. Barring rare complications, dogs and cats are not affected physically or behaviorally by the presence of a chip in their bodies.

A microchip scanner is required to scan the microchip. When the scanner is used over the body of a microchipped animal, it shows a unique identification number encoded in the microchip.

Where microchips are implanted: In dogs and cats, chips are usually inserted below the skin at the back of the neck, between the shoulder blades on the dorsal midline. Continental European pets may be an exception; they get the implant in the left side of the neck. The chip can often be manually detected by the owner by gently feeling the skin in that area. It stays in place as thin layers of connective tissue form around the biocompatible glass which encases it.

Horses are microchipped on the left side of the neck, half the distance between the poll and withers, and approximately one inch below the midline of the mane, into the nuchal ligament. Bird microchips are injected into their breast muscles. Proper restraint is necessary; therefore, the operation either requires two people (an avian veterinarian and a veterinary technician), or else a general anesthesia is administered.

Uses and Benefits: Microchipping is mainly useful in recovery of lost pets. They can also help in disputes over animal ownership. Animal shelters and animal control centers can save their time and money if an animal is microchipped because identification becomes easy and the animal can be returned to their owners. Nowadays, microchipping is becoming a standard in shelters as they are providing it as a part of adoption packages. Animal control officers are trained and equipped to scan the animals.

Now not only shelters but kennels, breeders, brokers, trainers, registries, rescue groups, humane societies, clinics, farms, stables, animal clubs and associations, researchers, and pet stores also have started using microchipping.

Many countries have made a microchip implant mandatory when importing an animal to prove that the animal and the vaccination record match. Microchip tagging may also be required for CITED regulated international trade in certain rare animals. For example Asian Arowana are so tagged in order to ensure that only captive-bred fish are imported.

Animals Recovery with the help of a Microchip: Effective pet identification and recovery depends on the following:

• A pet owner either adopts a pet at a shelter that microchips some or all adoptee animals or the owner with an existing pet brings it to a veterinarian (or a shelter) that provides the service.
   

• The shelter or veterinarian does a pre-scan to verify that the animal initially does not have a chip. Then he selects a microchip from their stock, makes a note of that chip's unique ID and inserts the chip into the animal with a syringe. The injection requires no anesthesia.
   

• Before sending the animal home, the vet or shelter performs a test scan on the animal. This helps ensure that the chip will be picked up by a scanner, and that its unique identifying number will be read correctly.
   

• An enrollment form is completed with the chip number, the pet owner's contact information, the name and description of the pet, the shelter's and/or veterinarian's contact information, and an alternate emergency contact designated by the pet owner. (Some shelters or vets, however, choose to designate themselves as the primary contact, and take the responsibility of contacting the owner directly. This allows them to be kept informed about possible problems with the animals they place.) The form is then sent to a registry keeper to be entered into its database. Depending on regional custom, selected chip brand, and the pet owner's preference, this registry keeper might be the chip's manufacturer or distributor, or an independent provider. In some countries a single official national database may be used. After receiving a registration fee, the registry keeper typically provides a 24-hour, toll-free telephone service for pet recovery, good for the life of the pet.
   

• The pet owner is also provided the chip ID and the contact information of the recovery service. This is often in the form of a collar tag imprinted with the chip ID and the recovery service's toll-free number, to be worn by the animal along with a certified registration certificate that can be sold/transferred with the pet. This ensures proper identification when an animal is transferred. A microchipped animal being transferred without a matching certificate could be a stolen animal.
   

• If the pet is lost or stolen, and is found by local authorities or taken to a shelter, it is scanned during intake to see if a chip exists. If one is detected, authorities call the recovery service and provide them the ID number, the pet's description, and the location of the animal. If the pet is wearing the collar tag, anyone who finds the pet can call the toll-free number, making it unnecessary to involve the authorities. (The owner can also preemptively notify the recovery service directly if a pet disappears. This is useful if the pet is stolen, and is taken to a vet who scans it and checks with the recovery service.)
   

• The recovery service notifies the owner that the pet has been found, and where to go to recover the animal.
  
  

Many veterinarians perform test scans on microchipped animals every time the animal is brought in for care. This ensures the chip still performs properly. Vets sometimes use the chip ID as the pet's ID in their databases, and print this number on all outgoing paperwork associated with its services, such as receipts, test results, vaccination certifications, and descriptions of medical or surgical procedures.

Animal species in which microchipping can be done: Many species of animals have been microchipped, including cockatiels and other parrots, horses, llamas, alpacas, goats, sheep, miniature pigs, rabbits, deer, ferrets, penguins, snakes, lizards, alligators, turtles, toads, frogs, rare fish, mice, and prairie dogs – even whales and elephants. The US Fish and Wildlife Service uses microchipping in its research of wild bison, black-footed ferrets, grizzly bears, elk, white-tailed deer, giant land tortoises and armadillos.

Worldwide use: Microchips are not in universal use, but there are legal requirements in some jurisdictions, such as the state of New South Wales, Australia. Some countries, such as Japan, require ISO-compliant microchips on dogs and cats being brought into the country, or for the person bringing the pet into the country to also bring a microchip reader that can read the non-ISO-compliant microchip.

In New Zealand, all dogs first registered after 1 July 2006 are to be microchipped. Farmers protested that farm dogs should be exempt, drawing a parallel to the Dog Tax War of 1898. Farm dogs were exempted from microchipping in an amendment to the legislation passed in June 2006. A National Animal Identification and Tracing scheme in New Zealand is currently being developed for tracking livestock.Australia has a National Livestock Identification System.

The National Animal Identification System is used in the United States. (It is applicable to farm and ranch animals rather than dogs and cats, and in most species other than horses, an external eartag device is typically used rather than an implant microchip. Eartags with microchips or those having only a visible stamped number can be used; either way, the 15 digit numbering scheme of the ISO type microchips is followed, using the U.S. country code of 840.)

Reported side effects or adverse reactions: RFID chips are used in animal research, and tumors at the site of implantation have been reported in laboratory mice and rats. Noted veterinary associations responded with continued support for the procedure as reasonably safe for cats and dogs, pointing to rates of serious complications on the order of one in a million in the U.K., which has a system for tracking such adverse reactions and has chipped over 3.7 million pet dogs.

Manufacturers: AVID and HOME AGAIN are the world’s largest sellers of microchips. AVID claims that its microchips help reunite as many as 1,400 pets with their owners every day, and HomeAgain touts a growing total of more than 400,000 pet recoveries. In India Kennel Club of India provides microchips with dog registration at a very nominal cost. The Kennel Club can be contacted on www.thekci.org.

Digital Angel Corporation has developed a microchip that will not only provide an ID number, but also take the temperature of an animal. The corporation claims that this device, which it calls the Bio-Thermo microchip, uses a specially programmed microchip to read and relate an animal's temperature. The microchip is touted as an easier alternative to the rectal temperature-taking method. DigitalAngel is also working on technology that will accurately measure such things as glucose levels, pulse oxygen levels and blood pressure.