Project Number: 5434-31000-016-04
Project Type: Reimbursable

Start Date: Oct 01, 2006
End Date: Sep 30, 2009

Objective:
The objectives of this research are to identify the basic mechanisms by which induced ovulation of smaller follicles results in decreased pregnancy establishment and embryonic survival in beef cows. Understanding these basic mechanisms will lead to identifying genes related to fertility.

Approach:
The primary experiment in this proposal is to use reciprocal embryo transfer of embryos derived from the ovulation of small or large follicles to the uterus of recipient cows that have ovulated large or small embryos to determine whether the primary obstacles to high pregnancy rates exist at the ovulatory follicle, luteal tissue derived from the ovulatory follicle or the uterus. Secondary studies will focus more closely on differences in the microenvironment of small verses large ovulatory follicles, luteal structures from small or large ovulatory follicles and the uterus following ovulation of small or large follicles and methods to reduce the proportion of cows that ovulate small follicles.