An edematous, shiny small intestine is observed in a pig. Which organism is most likely the cause?

• A. Salmonella
• B. Campylobacter
• C. Clostridium perfringens
• D. Escherichia coli

Answer: (D)

A pig with an edematous, shiny small intestine is most consistent with edema disease caused by a toxin-producing Escherichia coli strain. Certain E. coli in young, post-weaning pigs produces Shiga-like toxin (Stx2e) that damages vascular endothelium, increasing permeability and causing edema in multiple tissues, including the intestinal wall. The resulting fluid accumulation makes the intestinal wall appear swollen and glossy. Other listed organisms typically cause inflammatory or necrotizing enteritis rather than the diffuse edema that gives a shiny, stretched look to the intestine, so this presentation points toward E. coli as the cause.