Haemophilius Parasius and Swine Production

by 5m Editor
22 September 2008, at 8:45am

GLOBE - Haemophilus parasuis is a bacterial pathogen which is found in pig herds worldwide and is an important cause of disease and economic losses.

Infection with H. parasuis can result in a number of different pathologies including polyarthritis, polyserositis and meningitis in young pigs, and respiratory disease in older animals. As well as producing disease on its own, the bacterium can also be the cause of secondary bacterial infection in association with enzootic pneumonia or viral SRD (swine respiratory disease).

The bacteria are found in most herds, even high health herds, and outbreaks of infection are often associated with stress – especially as a result of transport. Outbreaks of disease occur in young pigs (3-6 weeks of age). The clinical signs of infection include depression, high temperature, loss of appetite, and sometimes a nasal discharge and cough. Individuals may become lame as a result of arthritis, with swollen, warm, painful joints.

Infection is spread via direct contact or respiratory droplets and a short cough of 2-3 episodes is a characteristic feature. Incubation may be as little as 12 hours, and H. parasuis attacks joint surfaces and membranes around the intestines, lungs, heart and brain. Infection develops rapidly and polyserositis, polyarthritis or purulent meningitis may develop within 36 hours. H. parasuis is not an uncommon cause of sudden death among piglets.

Piglets that survive continue to grow poorly as a result of continuing inflammation and may suddenly die, for example as a result of chronic pericarditis. Up to 15% of each litter may be affected.

Older animals may develop respiratory infections related to H. parasuis especially in non-immune herds.

Treatment and control relies on the use of antibiotics. Early use of appropriate antibacterial agents is usually successful in individual cases. Extended group treatment may be used to prevent the spread of infection to at risk animals.

There are at least 15 different serotypes of H. parasuis, with varying degrees of virulence. The bacterium is difficult to culture and post-mortem examination may reveal a wide range of pathological signs.

Further Reading

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