Studies have indicated the presence of ileitis on 95-100% of European farms, but have pig producers become complacent to the financial impact of the disease?

The presence of Lawsonia intracellularis, the bacteria that causes the disease, has been shown to affect production even where clinical signs such as diarrhoea or loss of condition aren’t apparent.

Maureen Prendergast, swine technical manager at MSD Animal Health, explains: “Lawsonia physically changes the lining of the gut and that affects daily weight gain and feed conversion even if the pig isn’t scouring.”

There have been some attempts to estimate the economic losses associated with ileitis arising from reduced productivity caused by the disease. One study showed a reduction of up to 38% in the average daily gain (ADG) and an increase in the feed conversion ratio (FCR) of up to 27%.

Lack of homogeneity within a batch is often a characteristic of infection, as some pigs will be more affected than others. Variation in growth caused by ileitis makes it more difficult to feed and market pigs adding further to the cost of the disease.

“It’s difficult to arrive at a firm estimate of monetary cost because of differences in production systems and levels of disease, but one study in the US estimated losses of between €5.39 and €15.27, depending on the age of pigs when infected and the severity of the disease,” explains Maureen.

“Most farmers are aware of the problem of ileitis and have adapted strategies to manage the levels in their herd, particularly in fattening pigs,” continued Maureen.

Hygiene, all-in all-out production systems and antibiotics can all play a part in minimising acute outbreaks and ensuring the disease remains manageable.

“However, sub-clinical infection still reduces productivity and there will also be increased costs such as veterinary services, antibiotics, feed bills, etc.

“When weighed against the benefit of reducing the impacts of the disease, farmers should consider vaccination as a cost-effective strategy to control infection with Lawsonia,” she concludes.

21 weeks’ immunity

A new vaccine against Lawsonia intracellularis from MSD Animal Health has recently been launched in both the Republic of Ireland and Northern Ireland.

The new vaccine has been proven to reduce diarrhoea, loss of daily weight gain, intestinal lesions, bacterial shedding and mortality caused by Lawsonia intracellularis infection.

The killed vaccine can be given by intramuscular injection from three weeks-of-age and it offers 21-weeks’ immunity to growing pigs.

More information

Farmers should discuss their vaccination regime with their vet who can also advise on infection control and on-farm biosecurity.

Further information is available from your veterinary practitioner or MSD Animal Health, Red Oak North, South County Business Park, Leopardstown, Dublin 18, Ireland.

MSD Animal Health can be contacted at: 01-2970220; or emailed at: [email protected].