Like humans dogs and cats also have staph living on their skin. Staph is a generally occurring bacterium. It creates problems when it is introduced into a wound or begins emerging in a region that is destabilized because of a cut or disease. A staph infection is a colony of staph bacteria that is not being destroyed by our typical immune system. You can find its symptoms like inflammation, necrosis, and pus-filled abscesses. Few diseases like Osteomyelitis (infection of the bone and associated tissues), pyoderma (pus-associated skin infection), and pyometra (pus in the uterus) are caused by staphylococci.