A Shooting Times reader was concerned about their dog's ears and the possibility of dog ear mites. Tony Buckwell had some advice.

Q: My German shorthaired pointer has recently started scratching her ears and shaking her head. Both ears are dirty and, when I clean them out, there appears to be an excessive amount of dark wax inside. There is no particularly bad smell, so I don’t think the ears are infected. What could be the problem?

Tony Buckwell is a veterinary surgeon with a special interest in gundogs. He had this advice about dog ear mites: As you might have noticed, the dog’s ear canal  first descends vertically before turning at right angles to continue horizontally to the eardrum. This anatomical configuration tends to make dogs particularly prone to ear problems.

Any foreign material, particularly grass awns, entering the ear has a tendency to descend this vertical canal where they become lodged and cause irritation. Typically, only one ear is affected — it would be unusual to find both ears affected simultaneously if this were the problem.

This anatomical arrangement also impedes drainage, so wax and other normal detritus can consequently build up in the vertical canal, where it acts as a focus for infection. This is much more likely to occur in dogs that have particularly narrow ear canals. Spaniels with heavily coated pendulous ears are also prone because this type of ear further inhibits ventilation.

Dogs can also become infested with parasitic ear mites, Otodectes cyanosis. This mite also infests other animals, especially cats (where they cause little or no problem). In dogs, however, ear mites stimulate the production of a dark brown waxy discharge and tend to cause intense irritation. Sometimes, if you look carefully, the tiny adult mites can be seen on the surface of this debris as tiny white spots. Secondary bacterial infection will usually occur and ear mites represent a major cause of external ear disease in the dog.

Take your dog to the vet so that they can examine the ears, diagnose the cause and treat it appropriately. Mention any other animals in the household, or if your dog otherwise comes into close contact with other animals, because if ear mites are the cause, these could represent a reservoir of infection and may need to be treated as well.