Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Biology and Microbiology

First Advisor

Donald P. Evenson


Biotechnology, even though in its infancy stage, has changed the realm of agriculture. A major portion of all crops planted around the world are transgenic or genetically modified by molecular means. A spectrum of issues about transgenics is being studied by scientists in order to answer questions from the concerned public about health safety, food value and nutrition, environmental impacts, regulation, and labeling. This study examines the health safety of glyphosate-tolerant soybeans and Bt (Bacillus thuringiensis) corn in nutritionally balanced diets using the mammalian testis (mouse model) as a sensitive biomonitor of potential toxic effects. Pregnant mice were fed a transgenic or a non-transgenic diet through pregnancy and lactation. After weaning, the young male mice were maintained on the respective diets. At 8, 16, 26, 32, 63, and 87 days after birth, three male mice and an adult reference mouse were killed, the testes surgically removed, and the cell populations measured by flow cytometry. Multigenerational studies were conducted in the same manner. The results of both the Bt com study and the glyphosate-tolerant soybean study showed that there were no differences in the testicular cell populations (haploid, diploid and tetraploid) between the mice fed the transgenic diets and those fed the non-transgenic or control diet. It was concluded that transgenic soybeans and corn in a balanced diet had no negative effects on cell proliferation and differentiation that occurs in the development of the testes and with ongoing cycles of spermatogenesis. These studies contribute to the growing collection of knowledge about transgenic crops that addresses the concerns of people around the world.

Library of Congress Subject Headings

Transgenic plants -- Physiological effect.
Soybean -- Biotechnology.
Corn -- Biotechnology.
Mice as laboratory animals.


South Dakota State University



Rights Statement

In Copyright