Julia Winter wrote:Hi Willy,
Border Collies do tend towards obsession, so you might want to try increasing his brain stimulation any way you can (I'm sure he'd be great at agility. Have you seen Treibball? Search on YouTube to see cool videos--it's herding without the sheep.) If you do that and the licking continues, it could be allergies.
My cat developed urine crystals that put him in the hospital. He is now on nothing but (grain-free) canned food, in order to maximize the water in his diet. We also had to get a completely new litter box, because he became convinced his litter box was evil once it started to hurt when he peed.