Lack of pigment around end of muzzle.

Question
We have two puppies, both one year old now ( What the heck were we thinking, huh???  lol ). A boxer, who is doing well and my rottweiler. He is of normal size and weight and has a normal appetite. The problem is that he  developed a distinct loss of pigment at the end of his muzzle at about the age of six months. We have had to change his diet to correct a digestive problem, after much trial and error, ( constant diarrhea- he now eats an easily  digestible food- Nature's Recipe - Lamb/Rice/Barley mix ). He's been to our vet to have a biopsy of the area , which came back inconclusive, nothing out of the ordinary found. We think that he may have an allergy to something in our soil as the area is inflamed after being out in the back two acres for exercise. Any ideas what we can do? Like I said, his diet is normal, this condition doesn't seem to be affecting
his appetite.

Answer
Sometimes this is as simple as changing food bowls. Dogs have often lost pigmentation from eating out of plastic bowls and some lose it from eating out of steel bowls. Some people switch to big glass bowls for this reason.

But what I am reading is that he has more than pigmentation loss if the area is inflamed. It could be a contact dermatitis from grasses or dirt. You can try some Benedryl for that but I would keep a log of what it looks like after he gets into the dirt, or the grasses.

Sometimes these things are a mystery. What you want to watch for is a distinct cracking appearance or dryness on the nose. That would be the signs of an auto-immune problem.

Otherwise I cannot tell you what it might be. If it were my dog I would change out the bowls and watch it.