Diarrhea, reduced appetite, and nervousness were observed following oral exposure of six pigs to freeze-thaw extract and living culture of E. coli strain 0139:K82:H1. The most significance gross change was the appearance of subserosal edema of the mesentry, especially of the mesocolon. Histological findings included perivascular edema of the brain and reticulum cells as well as lymphocytic aggregates in the renal cortex simulating early neoplasia. Edema of the submucosa of gallbladder, the duodenum, the spiral colon and the fundic stomach as well as the lymph nodes was also observed. The syndrome which was produced resembled, in many aspects, edema disease although some complicating factors were ob-