Pleuritis in pigs

Pleuritis is an inflammation of the surface of the lungs and can have a significant impact on pig health. Use this information to better understand the condition and how to prevent its spread.

Pleuritis is an inflammation of the surface of the lungs (the shiny membranes covering the surface). It used to be referred to as pleurisy.

Pleuritis may be caused by a virus such as flu, swine fever and the bacteria Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida.

Pleuritis can be difficult to diagnose on farm and may only be apparent at slaughter. Affected pigs may cough and be lethargic, with a reduced appetite, but these signs are not specific to pleuritis.

Members of the Pig Health Scheme are able to monitor pleuritis on their farm from the reports they receive.

Pleuritis can cause a number of problems for your pigs.

• Causes pigs discomfort when breathing
• Lowers the daily liveweight gain, which means lighter carcases and/or an increase in the number of days to slaughter. Pigs with pleuritis are likely to be 1.24 kg lighter than those without pleuritis
• Reduces the value of the carcase to both the farmer and the abattoir as it has to be trimmed
• Increases the cost of disposal at the abattoir while line speeds are reduced, which means higher processing costs

There are a number of measures you can take to reduce the risk of your pig herd developing pleuritis, such as:

• Buy stock from an appropriate source, depending on your herd health status
• Isolate incoming pigs for 6–8 weeks and check source health status with your supplier before integrating pigs into your herd
• Optimise stocking levels and ventilation in your buildings, ensuring draughts are avoided.
• If you're not already managing buildings all-in all-out, try to see if you can change your system to make this possible
• Make sure you have a thorough cleaning, drying and disinfection programme in place
• Review your control programmes for PCV2 and PRRS; even subclinical infections with these viruses appear to be important in heavily infected herds where the causal organism(s) has been identified. It may be necessary to consider a partial or complete depopulation–repopulation strategy. Discuss this with your vet
• Sign up to the Pig Health Scheme to monitor incidence of pleuritis on your unit

Things that could help reduce levels of pleuritis

• Cleaning, drying and disinfecting finisher pens before refilling
• Minimising contact between pigs of different age groups
• More downtime for grower pens before refilling to ensure sufficient drying time
• No mixing of pigs
• Minimal moving of pigs around the unit

When dealing with pleuritis, it is important to remember every farm is unique.

Management of the environment and stress will depend on the design of the piggery and the facilities available and may affect the success of any programme based on vaccination or the strategic use of antibiotics.

It is advised that producers work with their vet to develop a management plan that is appropriate for their farm. Give changes time to work and keep checking your pleuritis scores in the Pig Health Scheme and on partial and total condemnations.