Discharges from the nose can be clear fluid, mucus, pus, blood or a mixture of substances. The discharge can originate from the nasal area or from deeper in the respiratory tract, e.g. the lungs. There are several causes of nasal discharge, not all of them are infections. The prognosis varies depending on the cause the extent of disease when treatment is sought.
Any of a number of fluids produced in the respiratory tract can drain from your rabbit’s nose. This discharge may be seen on and around the nostrils, but as rabbits use their forepaws to clean their nose, the discharge, wet or dried, may also be seen on the fur on the inside of their front legs.
Rabbits breathe through their nose, so any nasal discharge may detrimentally affect their breathing. Aside from the obvious discharge, clinical signs may also include difficulties breathing, anorexia, sneezing and weight loss. Even with lower respiratory tract disease, coughing is very rare in rabbits.
Nasal discharge may be due to infectious or non-infectious causes.
- Bacteria such as Pasteurella multocida and em>Bordetella bronchiseptica commonly cause respiratory disease in rabbits.
- Viruses are rarely a cause of nasal discharge.
- In some cases of myxomatosis with secondary bacterial infection, a mucus/pus nasal discharge is seen.
- In the terminal stages of rabbit haemorrhagic disease, frothy blood originating from the lungs may discharge from the nose.
- Fungal infection may also affect the nasal cavity.
- Dental disease can obstruct the nasolacrimal tear duct which drains tears from the eyes down the nose. Secondary infection of the nasal cavity may also occur. Infection within the tear duct can drain into the nasal cavity.
- Trauma to the head, such as an attack by a predator.
- Nasal tumours.
- Foreign bodies, such as hay, hair or grass seeds, are common in rabbits, and can lead to infection and nasal discharge.
- Respiratory irritants, such as smoke, dust and high ammonia levels, irritate the nasal lining and secondary infection can occur.
- Allergic rhinitis is rare in rabbits.
- Other factors that are risk factors for respiratory tract disease include poor environmental conditions, e.g. poor ventilation or a dirty environment, overcrowding, other disease which reduces the rabbit’s ability to combat infections, and stress such as transportation.
After examining your rabbit, your vet may suggest some other tests to identify the cause of the discharge and help determine the severity of the condition.
Blood tests can show the overall health of the rabbit, in particular identifying signs of infection.
A deep nasal swab is useful to check for various infections. This is uncomfortable for the rabbit so your vet will need to sedate or anaesthetise your rabbit for this procedure.
Flushing the tear ducts is particularly useful if they are blocked by infection, but may take several attempts to achieve successful flushing. If the tear ducts are severely blocked or scarred it is sometimes impossible to flush them successfully.
Imaging, such as x-rays, endoscopy or computed tomography (CT) are useful to assess the structure of the nasal passages. CT scanning can be expensive, but should be covered by pet health insurance if you have it for your rabbit.
Biopsy of the nasal lining can help diagnose infections or tumours, but this is usually done under general anaesthesia.
General treatments include cleaning the nostrils, nutritional support, oxygen therapy (if your rabbit has difficulty breathing), nebulisation (this can be used to moisten secretions and also to deliver some medications), and anti-inflammatories/pain relief.
More specific treatments may be appropriate for certain diseases, e.g. antibiotics for infections or surgery for dental problems.
As with most diseases, the prognosis depends on the cause and extent of the disease.
Some diseases are readily treatable while others carry a very poor prognosis. For example, if a nasal foreign body is removed and the associated infection treated early, the prognosis is good. However, diseases like rabbit haemorrhagic disease are associated with a very high mortality rate. In chronic cases or rhinitis, a complete cure may not be possible and signs may recur. Nasal tumours are likely to need extensive surgery which may involve referral to a specialist surgeon.
Good care of your rabbit will help reduce the risk of many diseases. Provide your rabbit with a balanced diet made up of 80% grass and hay, 5% extruded nugget and 15% fresh greens, with fresh water available at all times and an appropriate environment in which to live.
To reduce risks of respiratory disease, AVOID the following:
- Sudden changes in ambient temperature.
- Poor sanitation: ammonia from waste (urine and faeces) irritates the respiratory passages, as can cigarette smoke and aerosols.
- Low humidity.
- Stress: young animals are especially at risk around the time of weaning; overcrowding can also lead to stress.