Katie Hackbart
Campus Address: Animal Science Building, 1675 Observatory Dr, Madison, WI 53706
Major Professor: Dr. Milo Wiltbank
Email: khackbart@wisc.edu
Degree Objective: Ph.D.
Background: MS - University of Wisconsin- Madison
BS - Brigham Young University - Idaho
Research Interests:
Polycystic Ovarian Syndrome is one of the leading causes of infertility in women, with as many
as 1 in 15 women being affected. It has been estimated that as many as 50-75% of women with PCOS
are insulin resistant, and that this insulin resistance may further disrupt the hormonal profile of these
women.
In previous research, we have used the cow as a model to characterize the effect that insulin
resistance has on follicular growth, deviation, and ovulatory capacity. The cow was selected as the
species of choice due to their monovular phenotype and ease of access. In this work, the
glucocorticoid Dexamethasone was used to induce insulin resistance. Cows that were treated with
Dexamethasone and were insulin resistant, as determined by elevated glucose and insulin levels, at
the start of a new follicular wave developed an anovulatory phenotype. Further work involved
challenging insulin resistant animals with GnRH at the time that an ovulatory follicle, as defined by
follicular size, was present on the ovary. In all cases, cows ovulated to this injection, indicating that
the follicle was functional with regards to the ability to ovulate to an LH surge. In addition, one
animal was challenged with E17β in the presence of an ovulatory follicle. This animal did not ovulate,
nor did she have an LH surge despite the rapid rise in E17β levels.
Publications:
Hackbart, K.S., R.M. Ferreira, M.T. Socha, R.D. Shaver, M.C. Wiltbank, P.M. Fricke. 2008. [Abstract] Effect of organic trace mineral (4-Plex®) supplementation on dry matter intake, milk production, health events, and body weight in dairy cows. 2008 Joint ADSA-ASAS Annual Meeting, Indianapolis, Indiana.