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 Feb. 11, 1947 a Spotted Poland China pig, age 4 months, was admitted to Stange Memorial Clinic. Upon admission the pig was suffering from an acute bloat. His abdomen was greatly distended and firm. He had begun to bloat, according to the owner, about 3 days previously. His condition had not improved and he was getting visibly worse.
"Non-Congenital Atresia Recti,"
Iowa State University Veterinarian: Vol. 9
, Article 12.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol9/iss3/12