When searching for a lost dog, it is SO much easier to tell area vet's, shelters, and add to posters, flyers, ads, etc. that the dog is tattooed. Helps to differentiate from the thousand other black labs in the pound!!! I was just at my vets office this morning when a lady brought in a mutt found running down the road. The shelters wouldn't take her (in heat and a brindle color so I am sure they thought "pit" mix) so the lady brought her in for vaccinations and to check for microchip, as well as to place a chip. I helped scan the dog to see if one was present and then we used same scanner on the chip that the lady brought in to use. The scanner did not show chip present in the dog, AND it couldn't read the Home Again chip that the lady brought- this is the same type of scanner that most of the shelters and vets use. Vet wasn't sure why the scanner wasn't reading the chip in the syringe (it worked on chips that the vet sold because we tested it) until I told her that some chips that Home Again and some other big name brands cannot be read on "normal" scanners due to the number of digits used. This chip was a 15 digit number!!! Most scanners only read 9-10 characters (numbers and letters).
So the moral of the story is: I believe in a backup!!!! One visible and permanent, one detectable and reliable (for the most part)and easily read by vets and shelters. Since my dogs go "naked" at home and when not on lead, tags and collars won't work for me and they are too easily removed and could get a dog hung up on something. When wearing a collar, the collar does have phone info for me and vet as well as the word "microchipped" on it. I will probably be adding "needs meds,special diet" as well