Lawsonia intracellularis

This enteric bacterium is causing different clinical diseases summarized as Porcine Proliferative Enteropathy (PPE, also known as Ileitis). Around the globe over 90% of farms are supposed to be infected with Lawsonia intracellularis and within those herds about 30% of wean-to-finish pigs may have detectable lesions at some point in time resulting in economic losses.

The chronic form of the disease is called PIA (Porcine Intestinal Adenomatosis) and is mainly causing reduced average daily weight gain, increased feed conversion ratio and uneven growth in pigs typically between 6 and 20 weeks of age, with or without clinical diarrhea. Other clinical forms include cases of acute hemorrhagic disease called Proliferative Hemorrhagic Enteropathy (PHE) occurring more commonly in young adult pigs (4-12 month of age). Animals suffer from an acute hemorrhagic diarrhea with blood loss into the gut. Animals show marked pallor and may present blood-red to tar-black feces. Only about 50% of animals survive the acute form and sows may abort due to PHE.

Antibiotics may be used to control clinical impact of PPE. However, due to the slow spreading of the disease in a group of pigs timing of treatment is difficult. Vaccination is more commonly used and is a very effective tool to control PPE.