By law all cats and dogs must be microchipped between the ages of 8 and 12 weeks. To accommodate animals that 'came of age' prior to the introduction of this legislation it also states that "all dogs and cats born after 10 April 2009 must be microchipped before they are sold or given away". In addition, it states that all regulated dogs (ie dangerous breeds or declared dangerous dogs) must be microchipped regardless of when they were born. This has made a fantastic difference to how quickly and easily animals are returned to their homes, it is especially important when lost animals are injured, by allowing their owners to be contacted and involved with life changing decisions.
So what are microchips and how do they work?
Microchips are a radio-frequency identification transponder contained within bio-glass. They way they work is really quite amazing. They contain no internal energy source, rather, they are powered by a magnetic field that is generated by a microchip reader. When activated the microchip to emits a radio frequency signal that informs the scanner of the unique code which is in turn linked with the details of an animal's owner on a database that can be accessed by vet clinics and animal shelters.
Microchips are commonly referred to as being similar to 'the size of a grain of rice' this is pretty vague and in fact they are usually a bit bigger. We use "Back Home Mini Transponders" - one of the smallest on the market and these have a diameter of 1.4mm and a length of 18mm.
In cats and dogs, microchips are implanted in the fascia/connective tissue at the base of the neck. However, they do not always stay there and it is not uncommon to find that they have migrated over to one side or even all the way down to an animals chest. Happily, we have never seen them migrate anywhere else and after some research on our online veterinary forum has found that neither have any of the other vets, so it seems thankfully, that the awful stories about microchips migrating into the spinal cord is a myth. Sadly there are a couple of reported cases of microchips being implanted into spinal cords. If you watch Magnus and Liv carefully, you may notice their technique involves picking up a large amount of skin and holding the microchip implanter parallel to the spinal cord. This makes implantation into the spinal cord impossible.
So, if migration into the spinal cord is not a potential side effect from a chip what is? Apart from discomfort when the chip is introduced through the skin, neither Liv nor Magnus have ever seen any side effects, not even pain following implanation! However, there are a few reported cases of fibrosarcoma (a malignant cancer) at the site of a microchip and an even lower number of animals that have developed a 'foreign body reaction' to the chip and extrude it from their bodies. Interestingly, if this occurs it is most likely to happen years later.
Microchips make a huge difference to lost pets lives, so long as the details that are linked to them are up to date. It is incredibly frustrating, and sadly quite common, to find that the details are out of date – either linked to old details or even a previous owner/the breeder! If you are unsure whether your pets details are current go to www.petaddress.com.au and enter your pet's microchip number (call us if you don't know it, we may have it on file otherwise we can scan your pet to find it). This will help you identify which database your details are held on, you can then follow the link to their website and follow the prompts to check/change the information.