Microchips
There was a recent thread talking about having ID on pets. People finding dogs sometimes remove a collar and will just keep a dog. There's more out there than you think. I've seen it many, many tim...
Forum Discussion
Q: What are some of the problems associated with microchips? How common are they?
A: The British Small Animal Veterinary Association (BSAVA) maintains a database of adverse reactions to microchips. Since the database was started in 1996, over 4 million animals have been microchipped and only 391 adverse reactions have been reported. Of these reactions, migration of the microchip from its original implantation site is the most common problem reported. Other problems, such as failure of the microchip, hair loss, infection, swelling, and tumor formation, were reported in much lower numbers. For a chart summarizing the BSAVA reports, read the AVMA's literature review on Microchipping of Animals.
Q: I've heard lately that microchips cause cancer. Do they?
A: There have been reports that mice and rats developed cancer associated with implanted microchips. However, the majority of these mice and rats were being used for cancer studies when the tumors were found, and the rat and mice strains used in the studies are known to be more likely to develop cancer. Tumors associated with microchips in two dogs and two cats have been reported, but in at least one dog and one cat the tumor could not be directly linked to the microchip itself (and may have been caused by something else). For more details on the studies, read the AVMA's literature review on Microchipping of Animals.
Q: I don't want my pet to get cancer. Should I have my pet's microchip removed?
A: We do not recommend that you have your pet's microchip removed, for two reasons. First, based on our review of the studies, the risk that your animal will develop cancer due to its microchip is very, very low, and is far outweighed by the improved likelihood that you will get your animal back if it becomes lost. Second, although implanting a microchip is a very simple and quick procedure, removing one is more involved and may require general anesthesia and surgery.
Current thinking now is that any insult to tissue (injection, bite, repeated trauma, etc.) causes the release of substances that in some individuals (very, very small percentage) may set up the circumstances where specific types of tumors could develop. There seems to be a familial (genetic) tendency. This is thought to be the mechanism where vaccine induced sarcomas develop in some cats.
There are ongoing investigations to try to pin down the exact mechanism, but the chances of developing cancer from an RFID chip are just about nil. Much greater chance of getting away, lost and no ID without the chip.
