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 March 24, 1955, I was called to see a 6-year-old Angus cow. A diagnoses of hydrops amnii was made. The exact freshening date was not known but was estimated to be about 3-4 weeks away. Since the fluid content had increased considerably in the last week it was decided to do a Caesarean section to save the cow.
McCracken, D. D. and Moore, R. A.
"A Case Report of Hydrops Amnii,"
Iowa State University Veterinarian: Vol. 18
, Article 3.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol18/iss1/3