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
Diagnostic imaging is very important in helping differentiate between certain medical situations. Ultrasound is a recent addition to the list of diagnostic imaging techniques and has become very beneficial in the area of large animal reproduction. Early pregnancy diagnosis and fetal sexing are two subjects which can be evaluated with ultrasound. Other applications include detection of abnormal uterine or ovarian structures and aspiration of follicles for sue with in vitro fertilization.
Hinkeldey, J. A. and Hopkins, S.
"Using Ultrasound in Bovine Reproduction,"
Iowa State University Veterinarian: Vol. 58
, Article 5.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol58/iss1/5