what causes ear mites in rabbits
Ear mange or ear canker in rabbits is caused by Psoroptes cuniculi, the non-burrowing rabbit ear mites. The Psoroptes cuniculi infestations together with coccidiosis are the most common parasitic infestations in both commercial and domestic or pet bunnies.
Once infested, the fecal and mucus that these mites produce causes inflammation and pain prompting this animal to want to bite, scratch or chew the affect areas. During scratching, any blood that comes out will serve as a further source of nutrients to these parasites. Head shaking is also common.
Although these pets can suffer from Otodectes cynotis, this species is common in cats and dogs. Therefore, this discussion is going to dwell entirely on Psoroptes cuniculi and not Otodectes cynotis.
Transmission and life cycle
Rabbit ear mites are contagious, and they transmitted via direct and indirect contact (through contact of the flaking crusts and handling by the caretaker) with risk factors such as overcrowding, poor hygiene, poor nutrition, high temperatures (associated with stress and heat stroke) and both internal and external stress.
Their lifecycle is about 3 weeks and their eggs hatch after 4 days and it has four stages (egg – larvae – protonymph – adult mite).
A severe infestation could have as many as 10,000 of these parasites  since they mainly live inside the ear canals, they can cause mild, moderate to severe damage to the skin lining this area depending on their numbers.
Therefore, treatment is very necessary to avoid them spreading from infected to non-infected bunnies as this can easily happen.
Finally, there are higher incidences of these parasites in rabbits that live in solid hutches and cages as opposed to those made of wire. However, those with wire flooring may not be comfortable and could cause sore hock
Rabbit ear mites symptoms
Clinical presentation will depend on the severity of infestation. Some of the early symptoms may be mild but if ignored, they may worsen. Common symptoms including the following:
- Head shaking and ear shaking make some of the early signs you may note.
- Chewing and scratching of ears, head, neck areas that can be mild to moderate to severe due to itchiness and pain in the affected area.
- One or both ear drooping (the affected one may be drooped)
- Thick yellowish to beige to brown exudates and waxy material will begin accumulating inside the canal and with time the entire inner parts the rabbit’s pinna. These exudates carry many of the mites, their feces, skin cells as well as blood.
- If not treated, the exudates begin growing into crusts (scabbing). These brown crumbly crusts and scales are painful and should not be removed (to avoid an eroded and bloody skin). They will slough off slowly once these mites die, and a new underneath skin tissue will grow again.
- Hair loss and skin peeling on the affected area are expected, normally on ears but can affect other areas including on the front paws.
- Secondary infections may soon set in especially the bacterial ones (but fungi and yeast can also set in) and they may result in abnormal skin thickening or may spread to the middle and inner ear causing various symptoms including head tilt, nystagmus and so on.
- Although Psoroptes cuniculi often occur inside the ear canal, signs of lesions and mites may also be noted on the perianal, abdomen, face, neck and feet as this parasite can spread these areas.
Finally, other symptoms including emaciation, death, deafness, among others which may be directly related to secondary infections caused by this infestation.
Are rabbit ear mites contagious to humans?
No. This is not one of the zoonotic infestations that can affect human beings. It is the fur mites that can temporarily infest human beings.
The various clinical signs will be an indication and your vet will use differential diagnosis to rule out other causes of symptoms such as ear and head shaking since other ear infections, vestibular diseases, Treponema cuniculi, mycotic otitis externa, and so on can be a cause of these symptoms. Note that Psoroptes cuniculi may not be visible by a naked eye.
Observation including the use of otoscope for examination may not be conclusive but may help see the extent of damage as well as if the tympanic membrane has been affected.
The tape method, swabs, skin scraping, vacuum aspiration using a filter paper can help detect these parasites. Scrapped samples should be observed under a microscope for larvae or mites while their fur may be used to check for the presence of eggs.
Deep scraping may also be recommended in cases where no eggs, larvae or mites are detected as they could have been caused by burrowing mites and not Psoroptes cuniculi.
Treatment for rabbit ear mites
There are several treatment protocols that will involve avermectins as well as some home remedies. Do not remove the crusts as this will be very painful and will leave behind a blood skin. The pain will also make your rabbit scream, want to struggle or even bite you.
Also, since these parasites are very contagious, it will be good to treat all rabbits that have been in direct contact or shared a common environment with the affected rabbits.
Rabbit ear mites ivermectin treatment
This is one of the avermectins commonly used to treat this parasite. You should consider “0.4 mg/kg, PO (oral) or SC (subcutaneous injection), 3 times at intervals of 14 days (life cycle of Psoroptes cuniculi is 21 days); 0.2 mg/kg has been found ineffective.” .
Infections are is more effective than when ivermectin is dissolved in mineral oils and used topically.
The rabbit ear mite treatment revolution
Alternatively, you can use other avermectins such as selamectin with Stronghold® used in Europe while in the US, you will use the Revolution®
Both the above avermectins are effective. However, they will not be able to kill the mites’ eggs. Fortunately, their lasting effect will ensure they kill the larvae once they hatch.
Besides the above, the moxidectin – Equest® and Quest® – have shown efficacy in treating these mites without secondary side effects when administered orally but some side effects might come with subcutaneous administration
Ear mites in rabbits home remedies and OTC
Besides the above rabbit ear mites Rx medications, the below natural treatments have been shown to help reduce mild infestations. They include the following.
- Eradimite or Otomite plus Ear Mite Treatment have been reported as effective in treating ear mites in these pets.
- Honey and water ( one hone teaspoon and two teaspoons of warm water) 
- Tea tree oil and honey mixtures may improve infestation
- Artemisia verlotiorum extract has shown efficacy in treating Psoroptes cuniculi 
- The use of “mineral oil, baby oil, or even vegetable oil”  with common ones being corn and sunflower oil, almond + olive oil, or mineral oil will smother the mites, fasten healing and soothe the affected areas.
- White vinegar and yellow dock extracts can also be helpful in managing rabbit ear mites at home.
Pain relief medications may be necessary to easy the pain including ketoprofen, carprofen, and meloxicam.
Once treatment commences, physical examinations and tests should be conducted to ensure reinfection does not occur. Prognosis largely depends on whether there have been severe middle ear secondary infections, damage on the tympanic membrane, and so on. It will be good if this has not occurred.
Also, consider bacterial, fungal or yeast infection treatments in cases where secondary infections have set in since they can spread to the middle and inner ear. Your vet will prescribe antifungals or antibiotics as he deems best. They may include systemic and topical antibiotics.
Avoid over the counter ear mite or mite medications since most contain neurotoxins such as pyrethroids and pyrethrins which may make your bunny to have symptoms such as tremors, coma, seizures, limb paralysis or even death including those with Piperonyl butoxide.
Finally, flushing and the use of Zymox Otic, an enzymatic solution may be recommended in case of excessive amounts of pus and debris accumulation.
Ear mites in rabbits prevention
Treatment is very important. However, the necessity of prevention cannot be underscored to avoid reinfection or spread of this contagious parasitic infestation. Some of the preventive measures include the following:
- Get rid of any organic material inside the infected rabbit’s cage or hutch. This will include changing their bedding, wood chips, litter bedding, and so on. Replace them with shredded paper which you will be getting rid of daily.
- Clean the cage each day. During the cleaning, avoid reusing anything that was present inside the cage. Vacuum carpets before disinfecting them but avoid shampooing or steam cleaning as it will only worsen the mite infestation.
- Disinfect thoroughly or get rid of grooming brush, combs, utensils to avoid spreading or transmission these mites from one bunny to another. Use boric acid including Indorex®, Vet-Kem Acclaim Plus®, Fleabusters®, among others during the disinfection exercise.
- Any insecticide used to disinfect their housing units need to be safe. Consult your vet on which ones are safe.
- Clean your rabbit’s ears regularly and remove any ear wax that may be accumulating.
Continue with these preventive measures until the parasite is completely gotten rid of and none of these pets have them.
Treatment of rabbit ear mites is straightforward if it started early before it predisposes your rabbit to middle and inner ear infections. Let your vet do the needed diagnosis once you notice any of the symptoms we have listed for a prognosis that is good.
Finally, do not ignore the condition since it can cause a lot of discomfort to your pet. Also, put in place preventive measures to avoid further spread.