Background and history

This is caused by a variety of bacteria, that gain access to the middle part of the ear which is responsible for balance and infection causes the piglet to hold its head on the affected side and to lose its balance.

Infection probably arises from the tonsils at the back of the throat and travels down the eustachian tube to the middle part of the ear. The common organisms involved include; Haemophilus parasuis, streptococci and staphylococci.

The condition is sporadic but common particularly in the weaned pig and sow and occurs occasionally in the sucking pig from 7 to 10 days of age. In some farms up to five percent of weaner pigs may be affected.

If treatment is prompt there is usually a good response.

If treatment is delayed there is the risk that infection will spread from the middle ear into the inner ear and directly to the brain, setting up a meningitis or encephalitis (inflammation of the brain). Actinobacillus pleuropneumonia has been identified in outbreaks of the disease.

Clinical signs

• The pig stands with its head to one side often shaking.
• As the disease progresses there is a gradual loss of co-ordination until ultimately the pig walks around in a circle eventually falling over.
• Jerky eye movements may be evident.
• Evidence of pain.
• Nervous signs i.e. fits, convulsions and meningitis may result.
• Unusual in young piglets.

Diagnosis

Based on clinical signs. Bacteriological examinations should be carried out if many pigs are involved.

Causes

Disease may be triggered by from:

• Mange.
• Skin trauma.
• Vice – Abnormal behaviour.
• Fighting.
• Septicaemia.
• Greasy pig disease.
• Joint infections.
• Porcine reproductive and respiratory syndrome (PRRS) infection.

The common organisms involved include:

• Haemophilus parasuis
• Streptococci
• Staphylococci

Prevention

• If there is a problem in your herd identify the time of onset of the disease and study the environment and other diseases for predisposing factors. These could include mange, skin trauma, vice (abnormal behaviour), mixing and fighting, greasy pig disease, joint infections and PRRS. Manage for these conditions accordingly.
• Consider preventative medication using amoxycillin long-acting injections given at the time just prior to disease onset.

Treatment

Early identification of the condition is essential to allow prompt treatment.

• The response to treatment in the weaner is usually good using either penicillin/streptomycin or amoxycillin.
• In acute cases it is necessary to inject the pig twice daily for the first two days and then follow up with long-acting injections. Long acting OTC can also be used.
• Cortisone injections are also of value as advised by your veterinarian.
• Treatment must continue for 7–10 days and complete recovery may take up to three weeks.

Disease in the sow is often severe and such animals are best culled if the response to treatment is poor.