Iowa State University Veterinarian Records, RS 22/6/0/9, University Archives, Special Collections Department, Iowa State University, http://www.add.lib.iastate.edu/spcl/arch/rgrp/22-6-0-9.html
On Dec. 23, 1940, near Brookfield, Mo., an outbreak of malignant edema in a herd of swine was observed. According to the owner 20 hogs developed clinical symptoms within 36 hours following his detection of the first sick animal. After this period no other affected animals appeared. A fox terrier dog known to have eaten a jowl from an infected carcass developed typical malignant edma symptoms within three days and died within a week.
Campbell, R. L.
"Porcine Malignant Edema,"
Iowa State University Veterinarian: Vol. 3
, Article 17.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol3/iss2/17