1.5 Why is Lawsonia intracellularis an increasing problem for the pig industry?

Since the development of antibiotics, the pig industry has made great progress in controlling diseases. The use of growth promoters made it possible in the last 2 decades to produce meat at lower costs with fewer enteric pathogens gene-rating clinical signs. Increased use of antibiotics, health management and hygiene have led to the disappearance of diseases such as transmissible gastroenteritis (TGE), porcine epidemic diarrhoea (PED) and swine dysentery, and covered up the clinical signs of proliferative enteropathy. With the introduction of the prohibition of antimicro­bial growth promoters in January 2006 in the EU, and furthermore, the recommendation of the World Health Organisation on the reduction of antibiotics use because of possible develop­ment of multiple resistant bacteria, Lawsonia intracellularis will become a prominent disease on many high health farms. Ileitis has become an increasing problem in Denmark since antibi­otics where prohibited in 2000.