Ileitis, also known as porcine proliferative enteropathy (PPE), is one of the most prevalent enteric diseases affecting pigs during the grow-finish phase1. While common, ileitis remains underdiagnosed2, resulting in losses that often go unaccounted for. Caused by the bacterium Lawsonia intracellularis, ileitis’ complex presentation and persistent nature continue to challenge producers and veterinarians.
Mild or subclinical infections can lower average daily gain (ADG) and worsen feed conversion ratio (FCR), while severe cases may lead to sudden mortality. Combined, these performance impacts can cost producers $5.98 to $17.34 per head, which can translate to tens of thousands of dollars annually.3
Understanding ileitis, including its symptoms, treatment options and prevention strategies, is key to maintaining herd health, optimizing performance, and protecting profitability.
Challenges in Ileitis Control
Preventing ileitis is challenging due to the high prevalence and ease of transmission of Lawsonia intracellularis. Because clinical signs are not always obvious, infection may continue before it is recognized, complicating control efforts and delaying timely intervention.
In some cases, the first indication of a problem may be a decline in average daily gain, feed conversion and/or size uniformity in a small percentage of pigs, rather than obvious clinical signs, such as scouring, across the entire population. This may be considered a “subclinical” infection, which can result in delayed recognition and intervention. As a result, the disease can persist undetected and impact performance long before intervention begins.
Because these signs can be subtle, accurate diagnosis plays a critical role in identifying infection and implementing timely control measures.
Management Strategies for Success
Understanding the prevalence of ileitis within a production system is an important first step in developing effective long-term management. Once Lawsonia intracellularis is established, elimination is difficult—but control is achievable through integrated management and treatment strategies.
An all-in/all-out production flow minimizes pathogen transmission between groups of pigs. This break in occupancy provides an opportunity to reduce the environmental load of Lawsonia intracellularis, which can persist in manure and on surfaces. Consistent pig flow also limits group mixing, reducing stress and preventing naïve animals from being exposed to infected carriers.
Thorough cleaning and disinfection between turns is especially critical for pathogens that are spread via the fecal-oral pathway like Lawsonia intracellularis. Maintaining high standards of barn hygiene creates an environment less conducive to disease transmission and helps limit the incidence of ileitis within a system.
Despite strong management practices and vaccination programs, ileitis remains a challenge on many farms. Lawsonia intracellularis can persist within production systems, and infection may still occur even when preventive measures are in place. Accurate diagnosis is essential for confirming infection and implementing timely treatment strategies. Initial surveillance for Lawsonia intracellularis in a population can be done through PCR testing and observations on a necropsy. Characteristic thickening of the ileum, a portion of the small intestine, can often be observed during postmortem examination in ileitis outbreaks. Disease should be confirmed by further examination of tissues, showing characteristic lesions on histopathology, and identifying the presence of Lawsonia intracellularis via PCR testing. Close monitoring of herd performance, combined with diagnostic surveillance and veterinary oversight, is critical for timely intervention.
Once ileitis is diagnosed, medication strategies can help combat the disease. Fast, effective treatment can deliver a strong ROI through improved pig health, productivity, and profitability. Because symptomatic animals often continue to drink water after going off feed, your veterinarian may recommend a water-soluble antibiotic for ileitis treatment.
Aivlosin® (62.5% w/w tylvalosin as tylvalosin tartrate) Water-Soluble Granules (WSG) offers a fast-acting, targeted option for ileitis management4. As a macrolide antibiotic, tylvalosin is active against Lawsonia intracellularis for clinical control. Its water-soluble formulation allows for easy administration and rapid uptake when it matters most4.
For more information on ileitis management or Aivlosin WSG, contact your Pharmgate representative or visit pharmgate.com.
1Schwartz, K., Knittel, J., Walter, D., Roof, M., & Anderson, M. (1999). Effect of oral tiamulin on the development of porcine proliferative enteropathy in a pure-culture challenge model. Swine Health and Production, 7(1), 5–11.
2Del Pozo Sacristán R, Swam H, von Berg S, Taylor AE. Vaccination Reduces Fecal Shedding and Improves Carcass Quality in Pigs with Subclinical Lawsonia intracellularis Infections. Vaccines. 2025; 13(7):728.
3 Holtcamp D. 2019. Economic losses associated with ileitis. MSD Animal Health.
4Stuart A et al. Intra-cellular accumulation and trans-epithelial transport of Aivlosin, tylosin and tilmicosin. Pig J 2007; 60:26-35
Available under prescription only. AIVLOSIN® is indicated for control of porcine proliferative enteropathy (PPE) associated with Lawsonia intracellularis infection in groups of swine intended for slaughter and female swine intended for breeding in buildings experiencing an outbreak of PPE. Control of swine respiratory disease (SRD) associated with Bordetella bronchiseptica, Glaesserella (Haemophilus) parasuis, Pasteurella multocida, Streptococcus suis, and Mycoplasma hyopneumoniae in groups of swine intended for slaughter and female swine intended for breeding in buildings experiencing an outbreak of SRD. For use only in drinking water of pigs. Not for use in male swine intended for breeding. People with known hypersensitivity to tylvalosin tartrate should avoid contact with this product. When used in accordance with label directions, no withdrawal period is required before slaughter for human consumption.
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