Page 5 - Clinical Connections - Spring 2022

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Page 5 - Clinical Connections - Spring 2022
P. 5

Exotics Service

     RABBIT EAR DISEASE

     Nadene Stapleton, RVC Exotics and Small Mammals

          ere at RVC  Exotics,  ear  disease   pus means such infections can become   of culture, and sensitivity tests performed
          remains one of the most common   expansive and rupture the bone of the   on surgical tissue samples (which are more
    H problems encountered in rabbits.    bulla. Such pathology is not easily palpable   accurate  than  culturing  pus  in  rabbits).
     Despite this, it is a seriously underdiagnosed   on physical examination and rabbits are   Flushing  of  the  surgical  sites  is  performed
     condition in companion rabbits – particularly   extremely good at hiding pain. This creates   daily for several weeks following the surgery,
     lop-eared  breeds,  which  are  over-  a situation where severe, painful ear disease   which requires a lot of dedication from owners.
     represented.                         remains undetected.                   Making sure that the owners and breeders
      Lopped  rabbits  likely  develop  the  ear   Some rabbits may develop a head tilt or   of lop breed rabbits as well as vets are all
     pathology as a result of the bent ear   facial asymmetry (Figure 1) as the first sign of   aware of this breed's predilection for ear
     conformation trapping wax in the lower canal,   an ear infection due to facial nerve damage.   disease is essential. This means any potential
     which  causes  inflammation  and  infection.   This leads to contracture of the facial muscles   rabbit owners can be educated about disease
     Excessive  amounts  of  wax  build  up  and   of  the  affected  side.  Unfortunately,  by  this   prevalence in the breed and ensure they
     migrate through a ‘path of least resistance’,   stage the problem is quite advanced.   have their rabbit insured to cover the costs
     often laterally out of the canal and under the   Computed  Tomography  (CT)  remains   of treating such a condition if it arises. Being
     skin at the location of the bend of the ear. This   the  most  effective  way  to  diagnose  and   aware of this disease will also prompt regular
     can sometimes be palpated as a swelling   determine the extent of ear pathology in this   veterinary checks to specifically look for this
     of the ear base.  Alternatively, this material   species (Figure 2.). In one retrospective study   difficult to diagnose disease.
     travels down through the ear drum into the   performed at the RVC, we found that 26% of   The intermittent use of ear cleaners
     deeper structures of the middle ear, causing   rabbits presenting for CT had ear disease and   designed to remove wax from ear canals may
     a painful abscess. In this scenario there may   45.5% of those diagnosed with otitis media   help reduce the risk – although there are no
     be no obvious swelling or other clinical signs.   were not being scanned for ear problems
                                          specifically i.e. a lot of subclinical ear disease
                                          is  diagnosed  on  CT  scans  performed  on
                                          rabbits for other reasons.
                                           Management can be medical or surgical
                                          depending on the severity of the condition.
                                          Surgery is most common as rabbits rarely
                                          present in the early stages of the disease.
                                          Surgery involves the removal of large
                                          sections of diseased ear canal, infected bone
                                          and pus and wax to reduce pain and suffering
                                          in rabbits who have already lost hearing. One
                                          of the most common techniques is partial ear
                                          canal ablation and bulla osteotomy (PECA-
                                          BO) (Figure 3).
                                           These  surgeries  are  extensive  and  often
                                          the wounds are sutured open – a technique
      Figure 1:  Facial asymmetry         called ‘marsupialisation’ to allow post-surgical
                                          flushing.  Despite  the  drastic  appearance  of
      Rabbits – unlike cats and dogs – are rarely   these rabbits postoperatively, this technique
     seen scratching ears or shaking their head,   gives us the best chance at preventing   Figure 3: PECA-BO
     even in the face of a severe ear condition.   recurrence of infection and is well tolerated.
      The caseous or solid nature of rabbit   Antibiotic choice is dependent on the results   rabbit-specific ear cleaners on the market. No
                                                                              studies have been conducted into prevention
                                                                              strategies so far.

                                                                              Nadene Stapleton was named UK Rabbit
                                                                              Vet  of  the  Year  at  last  November’s
                                                                              Burgess Excel Vet Awards. and the RVC’s
                                                                              Beaumont Sainsbury Animal Hospital was
                                                                              named Best Rabbit Practice of the Year.




                                                                                      For the RVC Exotics and Small Mammals
                                                                                    Service, please call: 020 7554 3528
                                                                                      Email:
      Fig 2: Red arrow indicates the pus-filled tympanic bulla. The air-filled normal bulla remains black  londonreferrals@rvc.ac.uk


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