Pus Filled Bump On Dog. Pus on a dog’s skin or fur is usually indicative of an infection or other skin problem. Warts are often referred to as papillomas, since they are caused by papillomaviruses.
The most important thing for you to do is stay alert to any lumps on your pooch and let your veterinarian know about them; When bacteria is introduced into the body, it can cause an infection. They're usually nothing to worry about but it may not go away.