The Respiratory System
Respiratory disease is very common in the rabbit. Rabbits are prone to pasteurellosis although there are other causes; for example: - overcrowding, stressors caused by heat/cold/proximity to predators, change in environment, (housing or type of bedding), transportation, change of owner or respiratory disease caused by another unrelated illness. Any signs of respiratory disease should warrant further investigation to prevent spread of disease to other rabbits being housed together.
Clinical examination
Rabbits are often compromised when presented for examination and therefore great care should be employed to prevent further distress. Rabbits are classed as “obligate nose breathers”. This means that they should only ever breathe through their nose. Any open-mouthed breathing is indicative of respiratory distress, the rabbit should be treated with oxygen and allowed to relax in a darkened cage. Try to observe the rabbit and take into account history from the owner prior to handling, paying attention to the following:
The image below is of Blaze. A 9 ½ year old male neutered Cotton Tail with known respiratory disease. Blaze is relaxed in this image. Note how his lips are parted – showing his incisors.
Signs and Symptoms
- Rapid shallow breathing
- Laboured breathing – exaggerated movement of the chest or abdomen
- Coughing
- Sneezing
- Snoring
- Discharge from eyes – (Dacryocystitis) and possible conjunctivitis/uveitis – pay attention to colour and thickness of discharge.
- Discharge from nose – results in “sticky” matted fur along forelimbs and paws – crusting of discharge around the nares/cracked skin or dermatitis from discharge possibly bloodstained fur.
- Pallor of mucous membranes
- Facial swelling
- Anorexia
- Depression
- Lethargy
The image below is of Kevin, an adult male neutered Netherland Dwarf Cross. Note how he has nasal discharge, resulting in dampened fur around the nares. He also has been pawing at his eyes – evidence of matted fur. Kevin was diagnosed with “snuffles” and meibomian gland dysfunction.
Common Diseases Affecting the Upper Respiratory Tract (URT)
These types consist of bacterial and viral; - in rare cases – fungal infections or parasitic pathogens.
The most common cause of bacterial diseases are as follows:
- Pasteurella Multocida
- Bordetella Bronchiseptica
- Pseudomonas spp.
- Staphylococcus spp.
Less commonly other pathogens such as Moraxella catarrhalis and Mycoplasma spp. have been found.
Common Diseases Affecting the Lower Respiratory Tract (LRT)
Diseases which affect the LRT can often involve the above causative agents; - however, Escherichia coli (E-coli), Chlamydophila, Mycobacterium, Pneumocystis Oryctolagus and cilia associated respiratory (CAR) bacillus have been found. Note: CAR bacillus is not the same variant as identified in the rat.
Viral Diseases Causing Respiratory Symptoms
Myxomatosis – spread by fleas and mosquitos usually fatal can cause URT symptoms. Other symptoms are swelling around the eyes and genitals. Vaccination is recommended as a method of disease prevention.
Rabbit Haemorrhagic Disease (RHD) – caused by the calici virus. Rapidly fatal disease with often no outwardly obvious signs. Some rabbits may have dyspnoea and haemorrhagic discharges from the nares and anus. Vaccination against this disease is available now and can be offered as a treatment against RHD alone or in combination with the myxomatosis vaccine. Advice should be sought from your veterinarian as to which type of vaccine is offered.
Herpesvirus – can cause respiratory disease, however this is a rare causative agent but should definitely be considered if rabbits are housed within a group. Presentation symptoms usually involve dyspnoea, conjunctivitis, periocular oedema, anorexia, weakness, ulcerative dermatitis and abortion. This disease has not yet been reported in domestic rabbits in the UK at the time of writing.
Diseases causing secondary respiratory symptoms
- Neoplasia (tumours)
- Respiratory irritants
- Allergic Rhinitis and bronchitis
- Foreign bodies e.g., grass seeds or small blades of grass
- Trauma
- Congenital malformation/abnormalities
- Cardiovascular Disease
- Gastric Dilation
Written by Kate Elson RVN
