What is a hallmark of Lawsonia-associated disease in foals (equine proliferative enteropathy)?

• A. Progressive weight loss with diarrhea, colic, depression and peripheral edema due to protein loss
• B. Acute fever with coughing
• C. Hematuria and flank pain
• D. Skin lesions

Answer: (A)

Lawsonia intracellularis causes proliferative enteropathy in foals, where the intestinal mucosa becomes thickened due to crypt cell hyperplasia and malabsorption develops. The clinical hallmark arises from this protein-losing enteropathy: foals show progressive weight loss with diarrhea, often accompanied by dullness or depression and colic signs, and develop peripheral edema from low circulating protein. This combination—ongoing wasting with diarrhea and edema due to protein loss—fits Lawsonia-associated disease best, because the condition centers on intestinal disease and protein loss rather than a primary respiratory, urinary, or skin problem.