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
Recently there has been much attention given towards the "pet animal" explosion. It has been reported that each hour approximately 10,000 dogs and cats are born in this country. A recent source states that this figure is exaggerated and is more like 3,500 per hour.
Grier, Ron L.
"Tubal Ligation - Alternative Sterilization Operation,"
Iowa State University Veterinarian: Vol. 35
, Article 5.
Available at: https://lib.dr.iastate.edu/iowastate_veterinarian/vol35/iss2/5