Ear problems in dogs are estimated to affect up to 20% of our canine friends. They are one of the most common reasons dogs are presented to our veterinary clinic
There are lots of causes of ear problems in the dog, but to understand the problems we must first look at the anatomy of the dogs’ ears.
The external ear of the human (the part of the ear that extends from the eardrum to the outside) is short, straight, and horizontal. This allows any fluid that might accumulate to drain straight out and air to circulate. The dogs ear canal, however, is very different and is shaped like the funnel of the old gramophone player. The purpose of this is to amplify sound. The first part of the canal is vertical, then after a 90-degree turn, the narrower horizontal canal ends at the ear drum. The canal is lined by cells that produce wax and help to fight infection. The canal anatomy makes it difficult for fluid in the ear to drain out, because it must fight gravity and travel upwards through the vertical canal to exit. Additionally, it is difficult to get medication all the way down to the ear drum when treating infections. Many dog breeds also have floppy ears eg Spaniels; excessively hairy ear canals eg poodles; or narrow ear canals e.g bulldogs, which causes increased warmth, darkness and a moist environment that bacteria and yeast absolutely love.
Ear infections occur when bacteria and yeast from the skin can work their way into a weakened ear canal usually from the above causes, but it can also happen if your dogs' immune system is compromised for example with an under active thyroid (hypothyroid). The canal can also become weakened from excessive moisture with dogs that swim frequently.
These are usually found in young pets as the mite is passed from the mother when feeding her puppies. The saliva from the mite causes intense irritation and frantic itching. Inside the ear canal we often seen a dark crumbly mass full of mites, eggs, dried blood and ear wax. This condition is easily diagnosed by the vet as the mites are visible when looking down the ear canal or seen on a microscope slide.
This is a very common cause of external ear infections (otitis externa). Often one of the first signs of allergies in the dog is inflammation and redness of the ear flap or external ear canal. This causes the canal to become swollen and itchy leading to self-trauma and often secondary infection due to damage to the lining of the canal, allowing bacteria and yeast to invade. Allergies are very common and can be from airborne allergens eg pollen, food allergies or contact allergies.
One of the most common we see is barley grasses and seeds. This is especially a problem with dogs with hairy ears eg Spaniels, as the seeds stick to the fur and then enters the canal. Dog can often present very acutely with a sudden onset in head shaking after running in long grasses, especially during the summer months.
Less commonly older dogs may develop tumours or benign polyps in their external ear canal. This can cause the accumulation of wax and limit air flow which predisposes them to infection.
A vet needs to assess your dog with a suspected ear problem, as the causes are numerous. Your veterinarian may quiz you about where your dog walks, the food he/she eats, if they swim frequently, if the ear problems seem to be seasonal problem or if your dog has any other underlying health problems that may predispose them to ear problems. Examination of the dogs’ ears with a specialised instrument called an otoscope, is imperative to visualise grass seeds, debris, ear mites or tumours, plus it is important to ensure the ear drum is intact. A small swab of the ear contents is often taken, to check under the microscope for bacteria, yeast or ear mites – this is called cytology. Swabs may need to be taken to send to the lab to culture the bacteria and find out which antibiotics may be best to treat the infection. Some dogs can be so painful and inflamed. that we may need to sedate or anaesthetise your dog to properly examine the ear canal. In extreme cases, referral to a specialist may be required for your dog to have further imagine such as a CT examination, to check for disease in the middle ear as well.
Early veterinary intervention is very important to help relieve pain and prevent ongoing complications. Treatment is best aimed at the specific cause eg Ears mites are easily treated with ear drops or topical therapies; Foreign bodies eg grass seeds can be removed; allergy therapy needs to be instigated if needed to decrease ear canal inflammation. With ear infections it is initially important to clean the canal and remove wax and debris, so we can visualise the ear drum and treatment drops can then penetrate the canal. Occasionally, if the ears are really sore, we need to sedate or anaesthetise the dog in order to do this. Depending on the cause and the organisms present, your dog may be prescribed a topical ear drop, oral medications, or both. Anti-inflammatories are also often needed to decrease inflammation and pain. In addition, your vet may require you to clean the ears regularly with a specific cleaner to prevent wax build up.
In some cases, your dog may respond rapidly to treatment and the problem is resolved, however, with many causes eg allergies or certain breeds, it may be a recurrent problem with lifelong management. In some circumstances your dog may be referred to a specialist dermatologist to help develop an ongoing treatment plan.
Left un-treated not only will your beloved pet remain uncomfortable, but the canal can become more thickened and inflamed, the cartilage lining the canal can become hard and calcified and the ear drum can rupture causing infection in the middle ear and loss of hearing - extensive surgery would then be the only treatment.
Regular cleaning with a specific dog ear cleaner which prevents wax build up, and early veterinary intervention when you notice a problem can help to prevent this!
Animal Care Vets is actively involved in our local community. We support a number of charities, including the SPCA. We also care for the Hawkes Bay Police dogs. Our customers know by experience that they can rely on us for sound advice on treatment options and that their pet is in the very best hands with our team.
