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.