I'm Dr. Jo and I'm here to help you with your question about Coley's feet. I'm so sorry he's having this problem, but glad you're looking for the information you need. You may join the conversation at any time by typing in what you want to say then clicking REPLY. That way we can chat back and forth until you're satisfied with the information I've provided.
By far the most common thing to cause this to happen is that Coley's feet are being exposed to some kind of irritant. Skin response to chronic irritation and inflammation by turning darker. This can certainly affect the skin and base of the nails
, as well as anywhere else on the body. Sometimes it's the result of exposure to some outside irritant; sometimes it's from the dog himself licking
a lot. Eliminating exposure to whatever is irritating the skin is how to fix this problem, although it may take some time.
It's important to note that once the skin is irritated and unhealthy, secondary opportunistic infections can develop. These infections can be bacterial or fungal, and your vet can make this diagnosis. If a secondary infection is also present, your vet can prescribe the necessary treatment to make the problem go away.
While bathing him is not likely to make the dark color go away (you are correct) it can help to remove any irritating substance. So bathing is still a good start.
Yes, urine is irritating enough to cause this kind of problem. But he would have to leave his feet soaking in it for a long time.
One final consideration is that this may be due to allergies. Dogs with allergies can lick their feet so much that they become discolored.
I hope this information helps.