The disease has three different presentations: porcine intestinal adenopathy (PIA), an abnormal proliferation of the intestinal mucosa; necrotic enteritis (NI), where the proliferated cells of the small intestine die and get detached with a gross thickening of the small intestine (hosepipe gut); and acute hemorrhagic ileitis,an hyper-acute inflammation which causes massive bleeding.
Alternative names: Lawsonia intracellularis, porcine intestinal adenopathy (PIA), necrotic enteritis (NI), hosepipe gut
Describes a group of conditions that imply pathological changes in the small intestine associated to the bacteria Lawsonia intracellularis, which, as its name indicates, lives inside the intestinal cells. The organism is present in all (or almost all) farms. The disease has three different presentations: porcine intestinal adenopathy (PIA), an abnormal proliferation of the intestinal mucosa; necrotic enteritis (NI), where the proliferated cells of the small intestine die and get detached with a gross thickening of the small intestine (hosepipe gut); and acute hemorrhagic ileitis, an hyper-acute inflammation which causes massive bleeding. In the latter there is massive bleeding into the small intestine, hence the name of bloody gut and this is the most common form in growing pigs and gilts.
The organism is impossible to keep out of farms probably because it also infects other species including horses. Infected feces are the major vehicle for spread around the farm.
Usually showing the hemorrhagic acute disease:.
- Pale skin.
- Look weak.
- Blood or tart color diarrhea.
- Might suddenly die.
Weaners and growers
PIA and NI clinical signs are different form hemorrhagic acute ileitis.
Porcine Intestinal Adenopathy (PIA)
- The pig appears clinically normal.
- Initially eats well.
- Chronic, diarrhea.
- Gradual wasting.
- Loss of condition.
- In some cases a pot bellied bloated appearance.
- Pigs with the chronic form of the PIA recover over a period of four to six weeks, however there can be considerable losses in feed efficiency and daily gain of up to 0.3 and 80g/day respectively. As a consequence there can be big variations in pig sizes.
- Not present
Causes / Contributing Factors
Not fully understood.
- Continuous flow pens.
- Lack of all-in/all-out production.
- Naive animals.
- Change of environment.
- Changes in feed.
- Continuous infection between batches appears to be a main means of spread.
- Organic production (do not use antibiotics): piglets are exposed at a very young age to the organism, which manifests clinically from 3 weeks of age.
Based on the clinical picture, post-mortem examinations, histology of the gut wall and demonstrating the presence of the organism in feces by ELISA or PCR tests. A serological test is also available.
Use antibiotics to treat sick pigs.
Strategic use of antibiotics at high risk times.
A good hygiene and the use of live modified vaccines administered orally, which have a good efficiency, are recommended.