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
The success or failure of a cow-calf operation depends greatly upon the reproductive efficiency of the herd and the pounds of calf weaned in the fall per cow in the herd. Some practical objectives for such an operation would be 95% conception rate and an average of 550 lbs. of calf produced per cow in a 12-month period. In order to attain these goals, sound management practices must be employed, and should include a comprehensive fertility program.
Johanns, C. J. and Johnson, Susan
"A Beef Fertility Program,"
Iowa State University Veterinarian: Vol. 36
, Article 5.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol36/iss1/5