Publication Date
Fall 12-1-2025
Document Type
Dissertation/Thesis
First Advisor
Singh, Pallavi
Degree Name
B.S. (Bachelor of Science)
Department
Department of Biological Sciences| Department of Chemistry and Biochemistry
Abstract
Shiga toxin-producing Escherichia coli (STEC) represents an important group of zoonotic pathogens that pose ongoing risks to public health through foodborne outbreaks and environmental transmission. This project evaluated the prevalence and genetic distribution of stx1 and stx2 toxin genes in fecal samples collected from Illinois bison Bison bison) managed under either commercial or preservation conditions. A total of 320 fecal samples were screened for STEC presence by performing enrichment culturing and confirmed by Polymerase Chain Reaction (PCR) for stx1, stx2, and uidA, which confirmed E. coli identity. Of all tested samples, 28.4% were STEC-positive, with stx2 (21.3%) far more prevalent than stx1 (6.2%). At the herd level, STEC detection averaged 54.5% ± 13% in commercial herds compared with 19.5% ± 10.0% in preservation herds (p=0.0167). These findings highlight how herd management, environmental exposure, and microbial ecology interact to shape pathogenic E.coli dynamics in large ruminants, supporting a One Health framework for surveillance. These results underscore the need for continued longitudinal monitoring of bison herds and further investigation into environmental and management factors that drive STEC persistence.
Recommended Citation
Baldocchi, Adam. Prevalence of Shiga Toxin-Producing Escherichia coli in Illinois Bison Herds. Honors Capstone, Northern Illinois University, 2025.
Suggested Citation
Baldocchi, Adam. Prevalence of Shiga Toxin-Producing Escherichia coli in Illinois Bison Herds. Honors Capstone, Northern Illinois University, 2025.
