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 the fifth of March, 1952, a three-year-old grade Appaloosa stallion was admitted to Stange Memorial Clinic for a cryptorchid castration. The owner had purchased the horse as a Yearling. Since that time, the right testicle had descended.
Dirks, Stephen F.
"False Cryptorchid Castration of a Stallion,"
Iowa State University Veterinarian: Vol. 14
, Article 12.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol14/iss3/12