The retina is a thin, delicate membrane that lines the back of the eye and is actually an extension of the optic nerve. In a healthy cat, the retina receives light, processes it, and passes it on to the brain. If the cells are damaged, it can’t send anything on. In a cat with retinal disease, the retinal cells are damaged and the eye is no longer able to properly transmit information regarding the light it receives. The visual image may be blurred, and part or all of the visual field may be blacked...
A discharge from both nostrils, often accompanied by fever, loss of appetite, eye discharge, drooling, coughing, or sores in the mouth suggests a feline viral respiratory disease. When both nostrils are blocked by swollen membranes, the cat sniffles, breathes noisily, and may breathe through his mouth. Because cats avoid mouth breathing whenever possible, you may see this sign only when the cat exercises. Any cat who is breathing through the mouth should be examined by a veterinarian.
Foreign bodies usually cause a discharge from just one nostril. This discharge can range from bloody to purulent. Allergic rhinitis usually affects both nostrils and the discharge is often serous.
Tumors, fungal infections, and chronic bacterial infections erode the nasal membranes producing a blood-tinged or bloody discharge. One or both nostrils may be involved. Cryptococcus is the most common fungal infection in the nose of cats. When there is blood in the discharge, the cat needs to see a veterinarian.
Bacterial infections become established when the lining of the nose has been injured by a foreign body or nasal trauma or by a prior viral respiratory disease. Nasal infections can cause sneezing, nasal discharge, noisy breathing, and mouth breathing. When nasal congestion interferes with the ability to smell, the cat loses his appetite and stops eating.
On occasion, infection spreads to the nasal cavity from the frontal sinus. This is often associated with an infected tooth root. Nasal infections can also be secondary to tumors in the nasal cavity. The chief sign of bacterial involvement is a nasal discharge that is mucoid, creamy yellow, or puslike. A bloody discharge indicates deep involvement with ulceration of the nasal membrane. The cat may also have a fever and may not be eating well.