Ear canker can be an extremely painful and irritating condition for your rabbit. Signs of this condition tend to appear 2-3 weeks after the animal is first infested with mites, therefore early detection of the mites that cause ear canker is important when trying to prevent this condition from taking hold.
What is ear canker?
Ear canker is a condition of the rabbit's ears caused by the ear mite Psoroptes cuniculi. Psoroptes cuniculi is a fairly common parasite of rabbits and occurs worldwide. The mites irritate the lining of the ear which causes oozing serum and thick crusts to accumulate within the ear canal. Lesions can spread to the face and neck and perforate through the eardrum leading to middle ear disease (otitis media) if the condition is allowed to progress without treatment.
How will I know if my rabbit has ear canker?
Ear mites very often cause the rabbit intense irritation, so you will notice your rabbit headshaking, ear flapping and scratching at the ears more often than usual. More severe signs may include twisting of the head (torticollis), spasms of the eye muscles and seizures. The rabbit may self-mutilate by the excessive scratching of the ears so you may also see cuts and scratches around the ears and the top of the head.
If you look down the rabbits ears you may notice crusts and scabs down the ear canal. The rabbit may resent you touching the ears as the condition is also very painful.
Long-term suffering can lead to further problems where the rabbit may lose skin from the ears and succumb to secondary infections which can damage the inner ear and may reach the central nervous system (CNS) so it is important to get veterinary treatment as soon as possible.
Can my rabbit be treated?
If you suspect your rabbit has ear canker, you should take it to see your vet as soon as possible, since the longer you leave it before treatment, the more serious it will get, and the longer the rabbit will suffer.
The recommended treatment is a course of ivermectin injections once every 10-14 days for three treatments, or topical selamectin or moxidectin. Your vet will advise on the best treatment course. All in-contact animals should be treated even if they are showing no symptoms as the infected rabbit will pass the mites by direct contact with another rabbit or when shaking their head, which allows the eggs and mites to contaminate the environment.
It is important NOT to manually remove the crusts from the ears. Once the mites have been killed with the treatment prescribed by your vet, the crusts will resolve on their own. Attempting to remove them is painful for the rabbit and can cause damage to the sensitive lining in the ear canal.
Painkillers (analgesia) in the form of a non-steroidal anti-inflammatory drug (NSAID) may also be prescribed to help with the pain and irritation the condition causes.
What else should I do if my rabbit is suffering from ear canker?
All bedding within the cage/hutch should be disposed of (preferably burnt) after each of the rabbit treatments. Enclosures should be carefully cleaned and disinfected to ensure there are no mites or eggs present which may cause further infections.