Nearly two-thirds of pork producers who participated in the 2003 National Ileitis Survey believe that subclinical ileitis costs more than the clinical form of the disease.

Despite the National Animal Health Monitoring Service finding Lawsonia intracellularis (bacteria that causes ileitis) in 96.2% of herds, 60% of those surveyed haven't identified subclinical ileitis in their herds.

That's because unlike clinical ileitis, which causes sudden diarrhea, bloody stools and even death, subclinical ileitis is more subtle, says Tom Marsteller, DVM, Swine Technical Services Manager for Elanco Animal Health. “Subclinical ileitis has a big impact on performance. Reductions in average daily gain, poorer feed efficiency and increased variation, as well as overall attrition in a group, are all signs of subclinical ileitis.”

Producers cited performance loss as the number one sign of subclinical ileitis; 58% said it's important to take corrective action even when 1 to 10% of pigs are affected.

Elanco's Tylan Premix is the only in-feed therapy approved for prevention and control of ileitis when fed at 100 grams/ton for 21 days.

The Elanco survey was conducted at World Pork Expo in Des Moines.