Ever wonder why a dog’s coloring sometimes looks like rust around the eyes? It can happen when there’s an increase in the flow of tears, say, when hairs are rubbing into the cornea or there’s an infection or a foreign body that has gotten into the eye. Tears contain proteins that bind to iron, and when the tears reach the outside of the body and are hit by oxygen, they literally rust.
If you see a rust color on the legs, it’s due to licking. Saliva, like tears, can bring on the staining. Causes of excess licking include a psychological trigger or allergies.
If a rust color persists anywhere on your dog’s body, it’s a good idea to take him to the vet for a workup to see if there’s an infection that needs to be treated, an allergy that needs tending, or perhaps anxiety that leads to compulsive licking and requires a behavioral solution.
