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 case histories of lead poisoning diagnosed in 63 herds of cattle over the past five years were studied. The toxicosis was found to be most prominent during the spring months and resulted in a 61 percent fatality rate. The clinical signs observed involved mainly the central nervous and gastrointestinal systems, as did the post mortem findings. The mean tissue lead levels were determined and correlated with the source of the toxicant.
Leary, S. L.; Buck, W. B.; Lloyd, W. E.; and Osweiler, G. D.
"Epidemiology of Lead Poisoning in Cattle,"
Iowa State University Veterinarian: Vol. 32
, Article 1.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol32/iss3/1