Several years ago, I was in a duck blind with a classmate from veterinary school. The ducks were slow, so we started talking about veterinary medicine, our practices, and life in general. I told my friend "I need to be a specialist in something; some problem that no one can solve." He replied "Labrador Retriever ears". We both laughed but there was a thread of truth in his assessment.
Chronic ear problems in hounds, pointers, setters, and retrievers can be frustrating for the owner and the doctor. I did not "specialize" in this area but I have learned some tips over the years that may help others deal with this frustration.
Ear infections can be broadly lumped into three categories: parasites, allergies, and infections. Infections can be further divided into yeast and bacterial infections.
The most common parasite is the well known ear mite. We used to see ear mites on a daily basis but currently, the use of topical flea products plus heartworm preventions has decrease the incidence of the little mite. The classic signs of ear mite infestations are head shaking and a dark brown discharge in the ear. Veterinarians can easily diagnose the mites with an otoscope or a microscope. Treatment is straight forward with one of several ear mite medicines available. The newer ones are three times stronger than the over-the-counter products and we have actually seen cases of ear mites resolve in 2-3 days with the right medicine.
If a dog has skin allergies they tend to have ear problems. The ear is lined with a type of "skin", so it follows that these allergic situations cause problems in the ear. The most common allergy in hunting dogs is called "atopy". Much like hay fever in people, atopy is the result of an allergy-causing molecule being inhaled in the nose! It is rarely something the dog is in contact with but occasionally, it can be a food allergy to something they are eating. The treatments for atopy are wide ranging and variable from doctor to doctor. But, they fall into two basic approaches: blood testing the dog and "vaccinating" the dog for the allergy (called "hyposensitization") or controling the situation with anti-inflammatory drugs, e.g. cortisone. Hyposensitization is the gold standard but it is expensive and takes weeks or months to complete. Many owners elect to just give the dog something to control the allergies. This can be cortisone type drugs via an injection or tablets given at home. Another, non-cortisone drug called cyclosporine is also useful in these dogs. It costs more but has fewer side effects. Regardless of your doctor's approach, these anti-inflammatory drugs decrease itching, redness, etc. helping reduce the irritation in the ears.
Yeast infections are very common in all hunting dogs' ears. These infections can be diagnosed with a simple examination under the microscope of a swab of the goop in the ear. Treatment varies from doctor to doctor but there are several excellent medications for treating yeast infections and, typically, the clear up readily. Alas, they are notorious for recurring, especially if the underlying allergy problems are not addressed. (Yeast infections are often secondary to those allergies mentioned above.)
In the past, we saw a lot of bacterial infections in hunting dog ears. In retrospect, most of those infections were probably yeast because thirty years ago, we did not know much about yeast infections in the ear. Regardless, there are a number of topical ear medicines that treat bacterial infections in the ear. Ideally, the doctor will take a swab of the pus and culture it to determine the exact germ causing the problem and also determine the best antibiotic to use for the infection. At times, we use the "shotgun approach" using a broad-spectrum drug that will successfully treat a wide range of bacteria but, again, the optimal approach is the lab work to determine the best course of treatment.
Prevention of ear problems in hunting dogs is, of course, the best approach. There are lots of old home remedies like white vinegar (lowers the pH of the ear via the mild acetic acid level) to plain old alcohol (not recommended). Personally, I clean my dogs ears once per month (I am lazy) but every week would be much better. Use a piece of cotton (no Q-Tip), a product like Aurocin (available from your vet but cheap) to physically clean the ear. Splash a bunch of the liquid down in the ear; rub the ear a bit, and let it dry the ear up.
One other thing: look in your dog's ears once weekly to catch problems before they get serious. Takes a second and saves you money and the dog discomfort.