Master of Science (MS)


Biomedical and Veterinary Medical Sciences - Veterinary Clinical Sciences

Document Type



The murine pathogen Helicobacter hepaticus has important confounding effects on research. Neonatal fostering has been studied in our laboratory for elimination of infection in mice. The purpose of our study was to examine fostering of pups from experimentally infected dams in male-absent parturition, and to determine the significance of gender and time on quantity of bacterial colonization in the cecum and feces of C57BL/6 mice. Approximately 20 C57BL/6 mice were fostered per day from one to four days of age. None of the C57BL/6 pups tested positive by PCR in fecal or cecal samples through four days of age. This data showed that removal of the male C57BL/6 mouse prior to parturition is crucial for extending the fostering period to obtain Helicobacter-free mice. In a second experiment, H. hepaticus infected mice were housed under varying arrangements to determine the effects of gender and housing on fecal and cecal colonization. Neither time or housing group affected bacterial fecal shedding. However, there was a significant overall effect of gender and a significant difference between male and female mice in both fecal and cecal bacterial copy number. Male fecal and cecal samples contained more copies of H. hepaticus than did female samples. Additionally, significant correlations between fecal and cecal H. hepaticus values were found both overall and by gender. Novel predictive algorithms were formulated to predict cecal bacterial colonization levels in fecal pellets. These findings should prove useful in Helicobacter elimination efforts, and in future work to further elucidate the role of H. hepaticus in transmission and disease.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

David G. Baker