By Theresa A. Fuess, Ph.D.
Information Specialist
University of Illinois
College of Veterinary Medicine

"Normal ears of dogs and cats have a relatively smooth inner lining with a minimal amount of wax buildup," says Dr. Sandra Manfra, small animal veterinarian at the University of Illinois Veterinary Medicine Teaching Hospital
in Urbana. "Any one of several problems can cause the ear canal to become filled with odoriferous debris. Your pet will probably tell you its ears are uncomfortable by excessive scratching and head shaking. Early treatment of ear
problems is important to prevent complications such as damage to the inner ear and hearing loss."

Ear mites (Otodectes) are a common cause of ear irritation and frequent ear scratching in cats. Ears infected with mites are often filled with dark brown, flaky debris. The mites can be seen when the debris is examined under a
microscope.

Allergies are a common cause of ear irritation in dogs. Allergies can be caused by pollens, molds, plants, fleas, and a variety of other substances. In addition to scratching their ears, dogs with allergies often lick their feet and rub their face.

Trauma to the ear from foreign objects, such as plant seeds or burrs, or from aggressive cleaning with cotton-tipped applicators can also cause pain and inflammation in a pet's ears.

Any of these conditions, if left untreated, can lead to additional and more complicated problems, such as yeast or bacterial infections. These infectious agents grow best in warm, humid ears that have little air flow. Thus, breeds that have very long or very narrow ear canals, animals that enjoy swimming, and those that live in hot, humid environments will be predisposed to ear infections.

Yeast (Malassezia pachydermatitis) is a normal inhabitant of the ear in small numbers. Inflammation of the ear, from any of the above causes, allows the yeast to grow in excessive numbers. Yeast-infected ears have a smelly waxy buildup. Bacterial infections can result in smelly pus-like drainage from the ear and can be extremely painful.

Your veterinarian can examine your pet's ear canal; test a sample of the discharge for bacteria, yeast, or mites; and choose the most effective treatment.
Your veterinarian can show you the proper way to clean and medicate the ears.

To prevent ear problems, keep your pet's ears clean and dry. It is more important to check your pet's ears regularly for dirt and discharge than it is to clean them. Look in your pet's ears once a week or whenever you are petting
it. Should they need cleaning, use only products and methods recommended by your veterinarian. Never clean with a cotton-tipped applicator any deeper than you can see. Finally, if your pet's ears require frequent cleaning, see your
veterinarian and treat the cause before complications develop.

For more information on pet care, contact your local veterinarian.