Progestin Concentrations Alter Follicle Characteristics and May Affect Quality of Oocytes (Eggs)

Authors

Bayli J. Slepicka, University of Wisconsin-Platteville
Jeremy L. Martin, University of Nebraska-Lincoln
Robin Ten Broeck, University of Nebraska-Lincoln
Michelle M. Baltes, University of Nebraska-Lincoln
Debra T. Clopton, University of Nebraska-LincolnFollow
Zachary C. Hall, University of Nebraska-Lincoln
Natalie C. Hart, University of Nebraska-Lincoln
Shantille G. Kruse, University of Nebraska-Lincoln
Robyn A. Longfellow, University of Nebraska-Lincoln
Jocelyn R. Wiarda, University of Nebraska-Lincoln
Karl V. Moline, University of Nebraska-LincolnFollow
Jeffrey W. Bergman, University of Nebraska-LincolnFollow
Robert A. Cushman, University of Nebraska-LincolnFollow
Brett R. White, University of Nebraska-LincolnFollow
Andrea S. Cupp, University of Nebraska-LincolnFollow

Date of this Version

1-1-2007

Comments

Published in 2007 Nebraska Beef Cattle Report. Copyright © 2006 The Board of Regents of the University of Nebraska.

Abstract

Cows were treated with two progestin concentrations to develop ovulatory follicles exposed to different hormone environments. Cows were assigned to Control Group receiving a CIDR for 7 days (4-6 ng/ml of progestin), or to MGA-14 Group receiving 5mg/head/day of MGA for 14 days (< 1 ng of progestin). Our hypothesis was that the MGA-14 treatment would develop larger, persistent follicles with less granulosa cells per follicle volume and may have altered gene expression profiles in oocytes and granulosa cells. Cows in the MGA-14 treatment had larger follicles and less granulosa cells per volume than controls, suggesting that their development mimicked persistent follicles and may be of poorer quality.