Robert A. (Bob) Cushman
Dr. Cushman's primary research is characterizing reproductive phenotypes that could act as indicator traits for fertility and reproductive longevity in cattle. Dr. Cushman collects phenotypic information from heifers and cows in the Germplasm Evaluation, Marker-Assisted Selection, and Twinner populations. Reproductive tract development is measured in females using ultrasonography to measure size of the ovaries, diameter of the uterine horns, diameter of ovulatory follicles, diameter of corpora lutea, and to count the numbers of follicles in the ovaries. Characteristics of the estrous cycle are collected using the Heat Watch computerized system. The phenotypic information collected is used for the discovery of genetic markers with the potential to identify the most fertile replacement heifers at an early age.
Superovulatory response of one ovary is related to the micro- and macroscopic population of follicles in the contralateral ovary of the cow.
1999 — Biology of Reproduction 60(2):349-354
The primordial to primary follicle transition.
2000 — Molecular and Cellular Endocrinology 163(1-2):53-60.
Characterization of biological types of cattle (Cycle VII): Influence of postpartum interval and estrous cycle length on fertility.
2007 — Journal of Animal Science 85(9):2156-2162.
Characterization of biological types of cattle: Indicator traits of fertility in beef cows.
2008 — Brazilian Journal of Animal Science 37(Special Supplement):116-121.
Evaluation of antral follicle count and ovarian morphology in crossbred beef cows: Investigation of influence of stage of the estrous cycle, age, and birth weight.
2009 — Journal of Animal Science 87(6):1971-1980.