Why is my Dog's Tongue Discolored?
Hi - my yorkie "Gretchen" has no teeth - so her tongue hangs out all the time - and I noticed that along the edge of the front of the tongue is somewhat rough and dry and has a thin black line - like drawn with a marker - it hasn't changed except the first time I noticed it, it seemed as if she had licked something black or dirty, but now it remains just a line - is there something I can use to keep her tongue moist? or should I be concerned and take her into her vet? - oh yes she is 7.5 years old - thanks,
I have met many dogs whose tongues lolled permanently out of their mouths. Most, like yours, had lost their front teeth. This disrupts the natural barrier that holds the tongue inside the mouth. Several others were brachycephalic dogs (Pugs, Bulldogs, Shih Tzus and the like) whose teeth and mouth simply weren't up to the task of restraining the tongue.
When a portion of the tongue sits continuously outside of the mouth it will become dry. After a while, the tissue may become firm, scaly, or discolored. The discoloration is a form of pigmentation that results from chronic mild irritation.
It is possible to moisten the protuberant portion of the tongue with a few drops of water at regular intervals. However, I'm not convinced that's necessary. I have yet to meet a dog who seemed to be suffering due to his dry or discolored tongue. Since the situation does not appear to be painful or to cause harm, it probably does not require intervention.
That said, I cannot make a definitive judgement about this matter since I haven't actually evaluated your dog. You should go to the vet. Hopefully she will confirm what I believe.