Veterinarians, animal shelters and rescue groups recommend getting your dog microchipped. Microchips serve as a permanent identification tag that contain owner contact information. The chip is a small device -- about the size of a grain of rice -- inserted under the skin between the shoulder blades where it stays for the entirety of the dog's life. The risks of microchip implantation are minimal, but many dog owners have concerns when it comes to reactions.
Most people have their dogs microchipped at a veterinarian. The procedure is simple, and requires no anaesthesia. The microchip is inserted with a twelve-bore needle. The injection of the microchip is usually painless, though it can cause some dogs slight discomfort. However, the American Veterinary Medical Association's 2009 microchipping report documents a few cases of life-threatening reactions. There have been reports of microchips being implanted in the spinal canal of small-breed puppies. The puppies suffered from weakness of all four limbs and recovered gradually after removing the chip surgically.
Swelling and Infection
Implanting the microchip causes minor swelling at the injection site between the dog's shoulder blades. Swelling should subside quickly but if it doesn't or you notice any other abnormalities such as oozing and possible infection or bleeding, contact your veterinarian.
Microchip migration is common. Ideally, the microchip should stay between the shoulder blades; however, it is possible for the chip to move, or migrate, to another location as it is under loose skin. If you are concerned, you can ask your veterinarian to scan your dog with the microchip scanner to find the location of the microchip.
There is some debate as to whether or not microchips cause cancer. The report "Microchip-Induced Tumors in Laboratory Rodents and Dogs: A Review of the Literature 1990--2006" written by Katherine Albrecht, Ed.D, a microchip expert and researcher, explains incidents where dogs have developed cancerous tumours at the implant site. This is becoming a widespread concern for many pet owners. Talk to your vet about any concerns you have with microchipping.