Causes of Dog Ear Infections

Dog ear infections can affect the internal and external ear and mat be caused by bacteria, yeast or ear mites. Dogs are more frequently affected by otitis externa, the external ear infection, but this may easily evolve into an internal ear infection, should the dog not receive medication. It is important to know the causes of dog ear infection, to be able to prevent the infections.


The ear canals are populated by a healthy number of harmless bacteria. However, when new bacteria occur, the normal balance is disrupted and the dog will have an ear infection. Bacterial ear infections are recognized by the yellow-brownish discharge.


The ear also features yeast cells, besides the bacteria. The yeast cells can also overgrow and this will lead to a yeast infection, which is very common in canines. The vet may detect if the infection is caused by yeast cells by analyzing the ear discharge, but typically, you can also tell if the infection is fungal if the discharge is pinkish or creamy white.

Ear Mites

Ear mites may lead to the occurrence of dog ear infections. This is due to the fact that the ear is not protected as the immune system has to fight off the mites and the dog will also scratch, which can facilitate the gathering of bacteria. In addition, the normal balance of yeast and harmless bacteria cells will be disrupted by the presence of the ear mites and the excessive production of ear wax.

Addition symptoms that indicate the presence of ear mites in your dog include fervent head shaking, a black or dark brown discharge, excessive ear wax production, visible ear mites and foul odor.

Factors Facilitating Ear Infections

There are a few factors that can facilitate the occurrence of bacteria and the overgrowth of yeast cells. These factors include:

  • Ears that are not cleaned on a regular basis. You need an ear dropper and a saline solution, a few cotton swabs and you can clean the dog’s ears once or twice per week.
  • Water trapped the dog’s ears
  • Moisture in the ear area, which will help the bacteria thrive
  • Injuries in the ear canal or ear area
  • A weakened immune system
  • Allergies, which cause scratching and the disruption of the normal bacterial and yeast cell balance in the ears

Some dog breeds are more prone to developing ear infections, due to the fact that they have longer ears that cover the ear canal, not allowing the air to circulate. Such dog breeds include Cocker Spaniels, Beagles, Poodles or Basset Hounds. However, all dog breeds may get ear infections.

Watch out for symptoms such as:

  • red, inflamed ears
  • head shaking
  • scratching of ears
  • discharges (black or yellow)
  • foul odor coming from the dog’s ears

Get help immediately, as the ear canals can shut completely and this may only be solved with surgery. An infection that advances can also affect the ear drums and cause temporary or permanent deafness.