Respiratory problems may also be due to obstruction of airways e.g. with discharge from an infection, swelling from an injury, inhalation of clumping cat litter. If the obstruction is immediately obvious and visible you may be able to remove it yourself by bathing the nasal area. Obstructions inside the nose or windpipe require veterinary treatment. Some short nosed breeds may show respiratory signs related to their altered facial proportions.
Nasal discharges indicate various problems. Pus indicates an infection or foreign object inside the nose. Trickles or bubbles of milk indicate cleft palate. A bloody discharge may indicate serious lung problems and, unless the blood is obviously from a superficial wound, bloody nasal discharge requires immediate veterinary attention.