Reproductive Aging Influences Ovarian Function in Beef Cows

Authors

Robert A. Cushman, University of Nebraska-LincolnFollow
Jennifer R. Wood, University of Nebraska-LincolnFollow
Rachael G. Slattery, University of Nebraska-Lincoln
Debra T. Clopton, University of Nebraska-LincolnFollow
Jacqueline Smith, University of Nebraska-LincolnFollow
Kevin A. Beavers, University of Nebraska-Lincoln
William E. Pohlmeier, University of Nebraska-LincolnFollow
Jeffrey W. Bergman, University of Nebraska-LincolnFollow
Karl V. Moline, University of Nebraska-LincolnFollow
Andrea S. Cupp, University of Nebraska-LincolnFollow

Date of this Version

2010

Comments

Published in 2009 Nebraska Beef Cattle Report (Lincoln, NE: December, 2008). Copyright © 2008 The Board of Regents of the University of Nebraska.

Abstract

Anti-Müllerian Hormone (AMH) has been associated with follicle number and age of the ovary. Therefore, our hypothesiswas that AMH was a biomarker for both follicle number and ovarian function in the beef cow. Ovaries were collected by flank laparotomy. The number of follicles increased as cows aged from 1.5 to 6 years and began to decrease thereafter; however, the size of the ovary continued to increase with advanced age. Expression of the AMH gene increased with increasing follicle number in 2-year-old beef cows. These results suggest that heifers with larger ovaries will have greater numbers of follicles and greater productivity, allowing them to stay in the production herd longer. AMH could be used to identify heifers of high reproductive potential at a very young age.