The saliva of a dog can stain it's fur. Your dog would have red staining on its beard from drooling and on his feet from licking. It's nothing serious.
The schnauzer could be having an allergic reaction to something (food, a chew toy) or could be licking an injured paw. Check with your vet to be certain.
You can but that sounds like the dog has lost the pigment in it's hair and that is nothing wrong with the dog. Or if the dog has a nerve condition and it lays and licks its feet it will lick the pigment out of its hair and the hair will turn a funny red color.
No, dogs suffer from heartburn and indigestion, their saliva becomes acidic, witch happens with the teardrops too, it paints the hair of the beard, the paw(licked), and around the eyes.
Lick stains are popular from eating colored morsel dog food either wet or dry. It can leave a pets face and feet looking redish or brown in color from the food dies in the morsels.
Your dog has been licking it's feet and the staining on the beard is caused my saliva also. You could try a whitening shampoo. I would be more concerned about WHY he's licking his feet. Dogs lick when they are bored, stressed, or anxious. They also lick if they have allergies or may be overdue for his grooming appointment.
I have 2 mini schnauzers and they both get red/brown stains on there face from licking thier beards after eating. It is from thier saliva. I use a whiteing shampoo and it dose the trick. One of our schnauzers licks her paws, which will cause the stain as well.
i own a schnauser and a high percentage have red beard and staining on their feet from licking. ive never seen anyone who can eliminate it. its natural and doesnt mean they have any medical problems.