Ear Infection

Otitis (Ear Infection)

Ear infections are unfortunately not uncommon in rabbits. Studies from meat rabbit farms show that approximately 32% of adult rabbits suffer from otitis. This aligns, depending on the breed, with observations in German veterinary practices.

Rabbits (Breeds) More Commonly Affected by Otitis

Studies show that lop-eared rabbits have a predisposition for outer and middle ear infections (outer ear infections often progress to the middle ear). A large proportion of lop-eared rabbits develop an ear infection during their lifetime. Lop-eared rabbits have a different ear anatomy compared to upright-eared rabbits: their ear cartilage is interrupted, causing the ears to droop. This creates a kink in the ear canal, which makes it difficult or impossible for earwax to drain properly, thereby promoting ear infections. Additionally, studies have shown that their ear canal is significantly narrower than that of upright-eared rabbits (the ratio of the diameter near the eardrum to the diameter of the ear canal shows a significantly smaller diameter in lops). Poor ventilation of the ear canal and reduced earwax drainage due to the drooping ears create an ideal environment for infections.

Other factors that can increase the risk of ear infections include:

• Small ears in dwarf rabbit breeds (narrow ear canals).

• Heavily furred ears.

• Very large rabbit breeds: These are also more frequently affected. This may be because larger breeds are predisposed to joint diseases, which can impair their ability to clean their ears. Poor grooming increases the likelihood of ear infections. Large rabbits are also more often from backgrounds where ear mites are present, which can trigger ear infections.
  Rabbits with the following conditions are also at higher risk for ear infections:

• Joint diseases (arthritis, spondylosis) or amputated limbs/other movement disorders: These impair the rabbit’s ability to clean its ears.

• Neurological conditions (seizures, head tilt): Studies indicate that 63% of rabbits with neurological issues experience ear infections.

• Respiratory illnesses, such as rabbit snuffles (Pasteurellosis): This increases the risk of ear infections to 85%. Pathogens from the nasal passages frequently travel to the ears, causing infections. Studies reveal that up to 30% of rabbits with snuffles may have a middle ear infection without showing external symptoms.

Symptoms: How to Recognize That Your Rabbit Is Sick?

Most rabbits with ear infections do not show symptoms. In a study, almost one-third of rabbits with ear infections showed no symptoms despite thorough examination. Some rabbits may only appear quieter due to pain, or in rare cases, may display aggressive behavior.

Lop-eared rabbits often have very dirty, sometimes blocked, ear canals. Small lumps at the base of the ear (ear base abscesses) or red, warm, or cold ear bases are also possible. When palpating the ear base, comparing both sides can help identify abscesses.

In rare cases, particularly when fungi cause the ear infection, rabbits may shake their heads or scratch their ears. Pendulum-like head movements (scanning), twitching eye movements (nystagmus), or a tilted mouth are also possible symptoms. Some rabbits may react with pain when their ears are intensely palpated or when their head is petted.

Rabbits with hearing loss or deafness due to an ear infection often become startled when approached from outside their line of sight, which can be mistaken for deep sleep.

Advanced ear infections can manifest symptoms similar to those of E. cuniculi infection, often leading to confusion between the two conditions (head tilt, balance problems, circling, eye twitching, etc.).

Due to the chronic inflammation in the body, affected animals usually have a generally weakened immune system, making it easy for pathogens (such as E. cuniculi, parasites, etc.) to break out, leading to other inflammations like tooth root infections, abscesses, and rabbit snuffles. Chronic pain in the head area causes rabbits to change their chewing behavior, which often triggers dental issues. Many rabbits with ear infections eventually develop dental (root) diseases. Some rabbits eat less due to pain, and in some cases, complete refusal to eat (pain-related behavior) or recurring digestive problems can also be observed.

Distinguishing Between E. Cuniculi and Ear Infections in Rabbits: Symptoms, Diagnosis, and Treatment

E. cuniculi and ear infections share similar symptoms but require different treatments. Both conditions can cause head tilt, rolling, seizures, and eye movements. In rabbits that test positive for EC, ear infections often develop as a secondary issue, as the E. cuniculi parasite takes advantage of the weakened immune system.

At the veterinarian: The middle and inner ear are located behind the eardrum, which means inflammation cannot be seen simply by looking into the ear. In addition to the EC titers in the blood and a neurological examination, an ear infection should always be ruled out through imaging techniques, with a CT scan being superior to X-rays.

Further information on specific, explanation-needed symptoms:

• Nystagmus (eye movements): Frequently horizontal or rotating movements.

• Aggressive rabbits: These animals are often poorly tolerated in existing groups or difficult to socialize, though only a few rabbits become noticeably aggressive.

• Slanted mouth: (Unilateral) facial paralysis or spasms. Initially, there is often a paralysis (facial paralysis, drooping corner of the mouth), and chronically a spasm (raised corner of the mouth on one side (ipsilateral hemifascicular spasm), while the other corner appears „drooping“). Sometimes, the eye may be half-closed, with the nictitating membrane protruding and/or impaired eyelid closure (Horner’s syndrome).

• Balance disorders: In case of inner ear infection (otitis interna), caused by damage to a nerve located there (vestibulocochlear nerve).

Be sure to consult an ear-specialized veterinarian who is not only experienced with small animals (dogs and cats), but also with small pets like rabbits and rodents! Only veterinarians with specific further training can treat rabbits, as they are only a minor topic during veterinary studies. When looking for a veterinarian, check for the ear symbol (indicating specialization).

Most rabbits show no obvious signs, only slightly dirtier ear canals and apathetic/calm behavior. Through a blood test, ear infections are often an incidental finding when the inflammation values are abnormal and the cause is being investigated (pseudoleukocytosis, leukocytosis). Unfortunately, not all ear infections cause inflammatory reactions in the blood.

In diagnostics, a distinction is made (multiple infections occurring simultaneously are also possible):

• Outer ear infection (Otitis externa): This can be detected by looking into the ear using an otoscope or endoscope. However, it is often hidden by earwax, the narrowed ear canal, and the bend in the ear of lop-eared rabbits. By pulling the ear upwards and using an appropriate otoscope or endoscope, it is possible to see behind the bend in some lop rabbits, where the infection usually resides. A deep swab can help differentiate between pus and earwax (normal earwax in rabbits is light yellow or beige, while purulent discharge is typically creamy and lighter in color, though it is hard to tell apart). Mites can also be detected, and the veterinarian can examine the colonization under a microscope (cytology). A bacterial culture may be taken to assess the colonization and determine an effective antibiotic.

• Middle ear infection (Otitis media): The middle ear is located behind the eardrum and is not visible from the outside. In severe cases, the eardrum may be bulging outward or pus may have entered the ear canal, but in most cases, it is not visible. In lop-eared rabbits, the eardrum is usually not visible due to the narrowed ear canal, and the outer ear may be blocked. In radiographs, only more advanced middle ear infections are visible (ventrodorsal view). CT scans, DVT (digital volume tomography), or MRI are more reliable methods for diagnosing ear infections, particularly in the early stages before the infection has significantly affected the bones.

• Inner ear infection (Otitis interna): These infections are rarely visible in radiographs from multiple angles, and a CT scan, DVT, or MRI is often required to diagnose inner ear infections. MRI is the most reliable method for diagnosing otitis interna.

Rabbits with ear infections often endure a long period of suffering because the diagnosis is not made correctly.

For example, about one-third of rabbits with head tilt do not have E. cuniculi but rather an ear infection. We are often contacted by owners whose animals have been diagnosed with E. cuniculi for „half a year without improvement.“ Upon further questioning, it turns out that „the veterinarian was sure the animal had E. cuniculi,“ but no diagnostic tests were actually done to confirm this. E. cuniculi is always a diagnosis of exclusion, as the E. cuniculi titer can be elevated due to immune weakness, even if the rabbit actually has an ear infection. Often, the outer ear wasn’t even thoroughly examined. Due to the prolonged lack of treatment, the ear infection is usually so advanced that it is difficult to manage or may have even spread. If left untreated, it can lead to dental disease, meningitis (inflammation of the meninges), abscesses, or inflammation in the spinal cord or lungs. Sometimes, the kidneys are inflamed, or the joints are affected. These conditions can lead to additional symptoms that may be mistaken for E. cuniculi. Left untreated for too long, the bone can even begin to dissolve or be severely damaged, and euthanasia may be the only option.

Since rabbits rarely show signs of pain, they often live with severe pain undetected.

E. cuniculi often breaks out in weakened animals, and many rabbits with ear infections experience an additional E. cuniculi outbreak. Therefore, even with a positive and high E. cuniculi titer, it is essential to investigate whether the ears are truly healthy.

Causes:

Middle ear infection can occur either through an outer ear infection with the rupture of the eardrum (descending) or from the nose via the Eustachian tube (ascending, especially with snuffles).

Infecting pathogens (nearly 80% from a single pathogen, over 20% from multiple pathogens) include both positive and negative microorganisms, such as:

• Staphylococcaceae (45%)
• Enterobacteriaceae (26.1%)
• Pasteurellaceae (11.5%)
• Pseudomonadaceae (6.8%)
• Streptococcaceae (4.3%)

Other causes include:

• Ear mange
• Bite wounds, abscesses
• Dental diseases, dental abscesses
• Poor ventilation of the ear canals due to floppy ears (lop-eared rabbits), very small or hairy ears, and narrow ear canals. Lop ears bend the ear canal, much like a kinked garden hose that no longer allows water to pass through. Additionally, the ear canal in lop-eared rabbits is anatomically narrowed.

Therapy: What helps?

Be sure to consult an ear-specialized veterinarian who is specifically experienced with rabbits!

Treatment of Otitis Externa (Outer Ear Infection):

The treatment depends on which pathogens caused the ear infection.

Which pathogens are the cause?
There are many pathogens that can trigger an outer ear infection. Cytology (taking a sample from the ear, staining it, and examining it under a microscope) can help determine which treatment should be used. Sometimes, a bacteriological examination (with an antibiogram to determine the most effective antibiotic) is also helpful. A swab is taken (using a head cannula to flush pus from the ear) and sent for analysis. Without flushing the ear with saline solution beforehand, the results are usually not reliable.

Treatment of the underlying pathogens:

• If bacteria cause the ear infection: Antibiotic eye drops or ear drops (such as Floxal) may be prescribed. These may be adjusted based on the antibiogram. Not all eye drops are suitable, as some can damage the hearing (ototoxic) if the eardrum is not intact. Initially, Enrofloxacin solutions are usually used, and these flushing solutions can be prepared by a pharmacy or the veterinarian. The pH of the ear is typically adjusted with Triz-EDTA-containing ear cleaners before each application, as Enrofloxacin does not work in an acidic environment.
  Studies in other animal species show that local antibiotic treatment can achieve 30-850 times higher concentrations in the ear compared to systemic administration. However, systemic antibiotic treatment is still important for ear infections, as treatment outcomes are much better with systemic antibiotics.Warning! Never use Surolan or other corticosteroid-containing ear treatments for rabbits!
• If yeast infections cause the ear infection: A 0.5% aqueous Miconazole flushing solution is typically prescribed by the veterinarian and prepared by a pharmacy for treatment 2-3 times a day. Clotrimazole (e.g., Canesten) is not suitable because all currently available products contain ototoxic ingredients. Systemic medications (such as Itraconazole or Itrafungol) are also useful and may be given alongside topical treatments.
• If ear mites cause the ear infection: These need to be treated with antiparasitic medications (e.g., Stronghold or Ivomec).

Cleaning the outer ear canal is recommended for every ear infection to help the treatments work more effectively (sometimes sedation is required for the first cleaning of blocked or narrow ear canals). For lop-eared rabbits, the veterinarian must carefully flush behind the kink in the ear (e.g., using feeding tubes, nipple attachments, or a syringe with tubing) because secretions often collect in front of the eardrum behind the kink. Due to the narrow ear canal in lop-eared rabbits, it is difficult to fully examine. An earwax-dissolving ear cleaner (cerumolytic) can help remove earwax, and to liquefy pus, Acetylcysteine (ACC/NAC) and intensive flushing may be required.

Ear canal care/adjusting the environment with ear cleaners: After the first cleaning, when the ear canal is fully cleared, regular ear care with ear cleaners is important. The choice of ear cleaner depends on the type of infection, the ear’s bacterial or fungal population, and the amount of earwax produced. The veterinarian will provide a recommendation. Depending on the amount of earwax, the severity of the infection, and the success of the treatment, the ear canal may need to be flushed more or less frequently with ear cleaner. For lop-eared rabbits, ear care must be maintained throughout life to prevent new infections (unless the ear canal is surgically widened). The ear cleaner alters the environment in the ear canal, helping to kill bacteria and fungi. Often, ear cleaners are more effective than antibiotics or antifungal treatments.

Important note: If the rabbit reacts strongly to an ear cleaner (e.g., skin changes in the ear or burning sensation after cleaning), the ear cleaner should be changed.

Important: Regular flushing and cleaning, along with the appropriate ear cleaners tailored to the specific condition of the ear, are crucial for the success of the treatment. If the treatment isn’t effective, it is usually due to infrequent flushing, the use of unsuitable cleaners, or incorrect application.

Initially, the ear should be cleaned once (or until the ear is clear) with an ear cleaner that dissolves earwax (ceruminolytic), and then thoroughly flushed. Afterward, hypochlorous acid should be applied to the ear. The owner can then apply a TrizEDTA-based cleaner once or twice a day to change the ear’s environment and break down the biofilm, allowing the antibiotic to work more effectively. Antimicrobial treatments can be applied about 15 minutes later.

Treatment typically lasts six to eight weeks. For lop-eared rabbits (if the ear canal has not been surgically widened), it is essential to continue ear cleaning with an ear cleaner weekly or monthly for life to prevent the inflammation from recurring.

Important: Regular flushing and cleaning, along with the appropriate ear cleaners tailored to the specific condition of the ear, are crucial for the success of the treatment. If the treatment isn’t effective, it is usually due to infrequent flushing, the use of unsuitable cleaners, or incorrect application.

Initially, the ear should be cleaned once (or until the ear is clear) with an ear cleaner that dissolves earwax (ceruminolytic), and then thoroughly flushed. Afterward, hypochlorous acid should be applied to the ear. The owner can then apply a TrizEDTA-based cleaner once or twice a day to change the ear’s environment and break down the biofilm, allowing the antibiotic to work more effectively. Antimicrobial treatments can be applied about 15 minutes later.

Treatment typically lasts six to eight weeks. For lop-eared rabbits (if the ear canal has not been surgically widened), it is essential to continue ear cleaning with an ear cleaner weekly or monthly for life to prevent the inflammation from recurring.

Active Ingredient	Preparation	Effect	Eardrum (ototoxic?)	Indications
Tris-EDTA and Chlorhexidine	Epibac Ear Cleaner	Antimicrobial Destruction of the biofilm	Only if the eardrum is intact!	Only suitable for young rabbits for preventive cleaning, or for a pure outer ear infection with an intact eardrum (supports the effect of Enrofloxacin as it alters the pH level, fluoroquinolones work best in an alkaline environment).
Tris-EDTA	TrizEDTA	Antimicrobial Destruction of the biofilm	Also effective with a ruptured eardrum	Suitable for all rabbits as a preventive measure, even if the condition of the eardrum is unknown. Applicable for all ear infections (supports the effect of Enrofloxacin as it alters the pH, fluoroquinolones work best in an alkaline environment).
Squalan	EpiSqualan	ceruminolytic (dissolves earwax)	also in case of a perforated eardrum	In cases of increased earwax production or earwax ‚buildup‘ in Angora rabbits due to the kinked and narrow ear canal, the ear canal should initially be cleaned with EpiSqualene. Repeated applications may be necessary until the ear canal is clear. It may also be used as a preventive measure for Angoras to keep the very narrow ear canal unobstructed. Not suitable for all individual animals!

Example of a treatment protocol for a perforated eardrum: Allow EpiSqualene to act, massage the base of the ear, and rinse the ear with NaCl-ACC solution until it is clear. Then, twice daily, use TrizEDTA (add ACC injection solution!) to disrupt the biofilm and create an antimicrobial environment. After 15 minutes, target the pathogens (e.g., Enrofloxacin-NaCl to combat bacteria in the ear). Finally, apply Granudacyn gel into the ear.

Additionally, oral mucolytics can be helpful (such as ACC children’s syrup and Bromhexine) as they help to liquefy thick pus and earwax and disrupt the biofilm, allowing antibiotics to work more effectively.

Pain relief is usually provided with Meloxicam (e.g., Metacam), typically at higher doses, possibly twice daily. This is often combined with other painkillers (usually Metamizole and/or Tramadol). Pain management also depends on the animal’s response to pain.

Oral antibiotics may be used as an adjunct for bacterial ear infections that are difficult to treat.

It is particularly important to support the immune system and use anti-inflammatory substances like ginger (which is anti-inflammatory and pain-relieving) and horseradish (which has antibiotic properties). These should be grated and introduced in very small amounts mixed with a favorite food, gradually increasing the quantity to ensure the rabbit consumes it. For example, grated apple, Cuni Complete mash, or mashed banana.

The effectiveness of the treatment is monitored through cytological examinations. Medications should only be discontinued when these show no signs of inflammation. This is crucial to prevent chronic ear infections, which can then spread to the middle ear.

Important: In Angora rabbits, inflammation is usually anatomically caused, meaning it often recurs. Regular maintenance is therefore critical: cleaning the ears with an ear cleaner (e.g., weekly or monthly), having the ears examined by a veterinarian with cytological tests twice a year, and having them X-rayed or, preferably, checked with CT, DVT, or MRI once a year.

For recurrent outer ear infections or in Angora rabbits, surgery is recommended: the type of surgical procedure depends on the location of the otitis:

– „Angora Surgery“: Lateral ear canal enlargement (or ear canal resection, also known as „Zepp surgery“ in cases of pure otitis externa): Removal of the ear canal wall to improve ventilation of the outer ear. This procedure effectively addresses the anatomical issue of Angora ears with minimal complications!

– Rare: Partial ear canal enlargement (in cases of pure otitis externa): Removal of a part of the ear canal wall at the base of the ear.

– Very rare: Total ear canal resection (in severe otitis externa): Removal of all cartilage from the outer ear canal. The tissue and skin can then be sutured back together, although a new opening may also be created. This is a relatively more complex procedure!

Treatment course of otitis externa in a Mini Lop rabbit:

Middle Ear Infection (Otitis Media):

There are two main approaches:

Conservative Therapy (without surgery):
Complete healing is not always achievable, and in most cases, the inflammation is only suppressed or temporarily controlled, which improves the quality of life. Typically, treatment needs to continue for several months.

• The key is using an effective antibiotic. If the eardrum is not intact, a sample should be taken from the ear for a culture and sensitivity test (antibiogram). This is done by flushing pus from the ear with a head cannula and sending the sample for analysis. Without flushing with saline beforehand, the results are usually not helpful. Penicillin (which must be injected) is often highly effective, but only if the rabbit is eating well. Ideally, this should be combined with an antibiotic that can penetrate the central nervous system (CNS). The combination of Metronidazole and Enrofloxacin (e.g., Baytril, Orniflox) is also often very effective.
• Pain management typically involves Meloxicam (e.g., Metacam) at high doses, possibly twice daily. It is often combined with other pain medications (Metamizole and/or Tramadol). The pain management approach should be tailored based on the rabbit’s pain behavior. Rabbits may not show signs of pain even with severe middle ear infections, often suffering quietly.
• The treatment of pathogens can be supported by N-Acetylcysteine (NAC, ACC), which has biofilm-dissolving properties and helps liquefy earwax and pus, making it easier for antibiotics to work and allowing better drainage of the pus. The ACC injection solution (e.g., Equimucin 200 mg/ml, either pure or mixed with saline 1:10) can be used to flush the ear, or Tris-NAC can be applied (before or during local antibiotic treatment). Oral mucolytics may also be useful in some cases.
• If the rabbit also has an outer ear infection or the eardrum is not intact, it is important to treat the outer ear with ear cleaners and a good flushing regimen (see Otitis Externa).

Surgical Therapy (with surgery):
Unfortunately, setbacks are common with antibiotic therapy. Additionally, the pus in rabbits is very thick, so while the inflammation may heal, the bulla (middle ear cavity) may remain filled. Setbacks are to be expected. For this reason, surgery is often recommended for middle ear infections.

The type of surgery depends on the location of the otitis:

• Ear Canal Enlargement (in Angora rabbits) to address the cause of the middle ear infection in the outer ear (outer ear infection). Afterward, intensive flushing and conservative treatment for the middle ear infection are performed.
• Suctioning: An incision is made in the eardrum (myringotomy, if still intact), followed by suctioning and flushing of the middle ear. Post-treatment includes antibiotic ear drops and CT monitoring. The bulla should not be thickened or dissolved for this procedure to be effective.
• Lateral Bulla Osteotomy (for non-intact eardrum, otitis interna, or otitis media together with otitis externa): This is often combined with one of the „otitis externa“ surgeries. The middle ear cavity (bulla tympanica) is drilled, scraped, and flushed. A permanent opening must be maintained in the ear, kept open with drains and flushing, until the middle ear is fully healed. If closed completely, the prognosis for the rabbit is poor!
• Rare: Ventral Bulla Osteotomy (for intact eardrum, otitis media without otitis externa): This involves exposing the middle ear through an incision, followed by scraping and flushing.

Inner Ear Infection (Otitis Interna):

Inner ear infections are almost always accompanied by middle ear infections.

• In many cases, intensive treatment of the middle ear infection with antibiotics, mucolytics, painkillers, etc. (see Otitis Media) can lead to a reduction of the inner ear infection.

• Severe inner ear infections with neurological symptoms are usually not treatable or operable, and affected animals should be euthanized. Some animals stabilize very well with intensive conservative therapy over several months, and, if stabilization occurs, surgery may be considered after stabilization.

Surgery – Yes or No?

Whether surgery is possible and appropriate for a specific case is determined based on the findings (CT, DVT, MRI, etc.). There is currently no standardized approach. Some veterinarians advocate for early intervention to slow or prevent the progression of the inflammation. Others recommend waiting until surgery is necessary due to the severity of the condition, such as when there is pressure on the middle ear (eardrum bulging outward), the bulla has changed or dissolved, or the animal shows symptoms— but not merely when the bulla is „filled.“

Surgery is not always the same:
In cases of pure outer ear infection in Angora rabbits, a relatively mild surgery (lateral ear canal enlargement after ZEPP) can be performed to correct the anatomical issue and prevent the ear infection from progressing to the middle ear. Surgeries on the middle ear (bulla osteotomies) are unfortunately very invasive, painful, and risky procedures and should be carefully considered on a case-by-case basis. Therefore, it often makes sense to operate early, before the infection spreads to the middle ear.

Prognosis?

Surgical procedures typically stop the inflammatory process, especially surgeries for „otitis externa,“ which often address the poor ventilation of the ear canal and generally have a good prognosis. The situation is different for surgeries related to „otitis media.“ While these surgeries usually lead to the resolution of the inflammation, they may also just buy time, as relapses can occur in animals. Some animals regain a very good quality of life after surgery, and even „quiet“ rabbits become lively and active again. The prognosis tends to be better for descending ear infections (from the outer ear to the middle ear, as seen in rabbits) than for ascending infections (such as in rabbits with rhinitis). Pre-existing neurological symptoms (e.g., walking in circles, head tilt, facial nerve spasms, etc.) are not corrected by surgery. However, head tilts often improve with intensive conservative treatment.

The success of the surgery depends on a highly experienced surgeon who has performed many ear surgeries on rabbits. These experts can draw from their experience to determine in which cases surgery is the right treatment for the individual animal. Only a few surgeons in Germany are skilled in rabbit ear surgeries, and a rabbit-experienced veterinarian should coordinate the medication treatment as well. The rabbits should be intubated for the surgery, and there must be excellent pain management in place!

Middle ear surgeries are very complex procedures that require intensive care for about one to two weeks. Be prepared to provide intensive care for your rabbit, administer medication multiple times a day, possibly supplement feeding for several days, attend veterinary check-ups, and potentially administer eye drops several times a day if eyelid closure is affected. Excellent pain management is crucial!

Possible complications include, among others, wound healing issues at the ear (which are very common but manageable), facial nerve damage (leading to temporary eyelid closure problems, spasms… usually normalizes after 2-3 weeks), severe pain and refusal to eat, and head tilt (rare).

Ear canal enlargement/Zepp surgery/“Lop ear surgery“

The images show: 1) the day of the surgery, 2) the day the stitches were removed, and 3) the follow-up examination two weeks later. The rabbit underwent surgery on both sides.
Photos: Veterinary Practice Holt/Alexandra Riecken

Feivel also underwent surgery to enlarge the ear canal opening enough to allow air to reach behind the lop-typical fold to the outer ear, enabling the inflammation to heal.
Photos: Saskia Hinze / Schneidersgarten Veterinary Practice

And here is another example of the healing process:

Wound complications are common but manageable. There are 12 days between the first and the last photo:

Prevention

A significant number of lop-eared rabbits develop ear infections over the course of their lives. A CT study shows that lop-eared rabbits have a predisposition to outer and middle ear infections. The drooping ear flap causes poor ventilation of the ear canal, creating an ideal environment for bacteria and yeast to thrive. These pathogens can trigger infections. For this reason, lop-eared rabbits can be considered a breed with welfare concerns, and the breeding of lop-eared rabbits should not be encouraged by acquiring new animals. Rabbits with respiratory conditions or other chronic inflammatory diseases may also be prone to otitis.
Such rabbits should therefore follow a specialized ear care program.

Preventing Otitis Through Proper Ear Care
Lop-eared rabbits are often affected by chronic inflammation of the ears throughout their lives. While proper care cannot always completely prevent such inflammation, it can significantly reduce the risk.

Recommendations for Preventing Otitis:
Regular Ear Cleaning: Depending on the condition of the ears, clean them weekly or monthly using an antibacterial and wax-dissolving ear cleaner containing Tris-EDTA (and chlorhexidine if the eardrum is intact). Start this routine early, ideally when the rabbit is still young. Suitable products include Epibac Ear Cleaner or TrizEDTA for cases where the eardrum is damaged.
⚠️ Note: Some ear cleaners may irritate the ears due to ingredients unsuitable for rabbits. In rare cases, even appropriate ear cleaners may cause reactions in particularly sensitive rabbits.

Deep Cleaning and Flushing: Perform thorough ear cleaning and flushing during anesthesia or sedation when necessary, or as required.

Early Detection of Otitis

• There are steps you can take to detect otitis in its early stages, which is particularly important for lop-eared rabbits:

• Weekly Examination: Gently palpate the base of the ears weekly to check for slight swelling, warmth, sensitivity to pain, or signs of itching.

• Twice-Yearly Ear Swabs: Have a sample taken from the ear canal twice a year for microscopic analysis to monitor the status and detect early signs of infection (e.g., during vaccination visits).

• Annual Imaging: Perform a CT, CBCT, or MRI scan (to assess the middle and inner ear and detect early stages), or at least an X-ray to identify more severe ear infections.

• Symptom Awareness: Watch for head shaking, ear scratching, a crooked mouth, or other symptoms. Make sure you’re familiar with these signs!

Comparison of a Healthy, Open Ear Canal and an Inflamed, Narrowed Ear Canal

Further Examples:

Mickey with Circular Movements, Snuffles, and Head Tilt

Mickey had a tilted head for 10 months and was initially treated for E. cuniculi (EC) because his blood test showed a positive titer. When his condition didn’t improve, he was left untreated. I decided to pursue detailed diagnostics to determine the cause of his head tilt. It turned out that Mickey had an ear infection. I treated him for both E. cuniculi and the ear infection, and within just a few days, his head straightened completely. His snuffles also improved significantly.

Rabbits with ear infections often tilt their heads to alleviate the severe pain they experience. This is frequently mistaken for E. cuniculi, and proper diagnostics are often overlooked. As a result, many rabbits suffer for months from agonizing pain (anyone who has ever had a severe middle ear infection can imagine how unbearable it must feel).

In Mickey’s case, his ear appeared completely normal from the outside. Even using a camera to inspect the ear canal didn’t reveal anything unusual. The inflammation was only visible on a head X-ray. Blood tests can also indicate signs of inflammation.

Years ago, E. cuniculi was relatively unknown, and it was difficult to find a veterinarian who could diagnose and treat it correctly. Today, however, many issues are mistakenly labeled as „E. cuniculi,“ leading to countless animals being incorrectly treated for this condition—even when they are actually suffering from a different, painful disease. As a result, people often say, „My rabbit died of EC.“ In reality, rabbits don’t die from E. cuniculi if their kidney function is monitored via blood tests and they receive proper treatment from the beginning. Rabbits can die from kidney failure caused by E. cuniculi, but only if it goes untreated or is mismanaged.

Unfortunately, many rabbits endure immense suffering or die from other diseases that are misdiagnosed as EC.

Mickey was fortunate because his ear infection wasn’t too advanced, and I ensured he received proper diagnostics and treatment. In rabbits with untreated ear infections that persist for months, the infection often leads to bone erosion. In such cases, euthanasia is often necessary, or the animal dies from complications.

Paul with Crooked Mouth, Head Tilt, and Hind Limb Paralysis

Since July 2015, Paul had a „crooked mouth.“ Our veterinarian couldn’t identify the cause or offer a solution, and we couldn’t find any information online either.

Then, in the spring and again in November 2016, Paul’s hind legs suddenly gave way. He was diagnosed with a suspected back problem. As his symptoms didn’t improve, we pushed for further treatment. He was treated twice for E. cuniculi (EC), and both times the symptoms disappeared, and Paul seemed to return to his normal self. However, in November, he developed a slight head tilt that did not fully resolve.

On December 27, 2016, he collapsed again. The following day, we obtained the necessary medications to address what we suspected was an EC flare-up. These included Baytril, Panacur, and a Vitamin B complex. Unfortunately, Paul’s condition worsened significantly, and due to the holiday season, we had to consult a substitute veterinarian.

Paul was examined inadequately, only through palpation and visual inspection. The diagnosis was simply „It must be EC.“ He received injections of corticosteroids and enrofloxacin. The treatment had an immediate positive effect, and the next day, he was treated identically. While he improved noticeably, by the weekend, he collapsed again, and we took him to our regular veterinarian the following Monday.

Our regular vet also diagnosed EC and, for the first time, suggested euthanasia, as Paul was barely able to sit up. We insisted on further diagnostics, and a week later, an X-ray was taken and blood tests performed to rule out a middle ear infection (otitis media). Although the X-ray was taken at an awkward angle, it later became clear that it revealed a deformity, which our veterinarian did not recognize. The blood test showed no EC titer and no signs of inflammation.

At this point, Paul needed intensive care for three weeks, as he could only lie down. After our insistence, Paul was treated with Chloramphenicol Palmitate, and we had to hand-feed him. After 10 days, the antibiotic was stopped, and Paul began eating on his own again. He was much improved but could still only lie down.

We sought a second opinion. The new veterinarian performed a CT scan, which revealed a long-standing otitis media and a brain abscess with bone erosion. This was also the cause of his „crooked mouth“ (ipsilateral hemifacial spasm/facial nerve paralysis) that had persisted since 2015. The antibiotic treatment, though effective, came about 1¾ years too late.

Sadly, Paul had to be euthanized.

Before-and-After Photos of Left Ear Infection and EC

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