| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg 24061
Observing cows in estrus and inseminating them at the optimum time are necessary steps for effective reproductive management of a dairy herd. However, larger herd sizes can lead to reproductive inefficiency and decreased profits on dairy farms. Synchronization of estrus behavior through pharmacological control has been used to improve reproductive efficiency. Methods of synchronizing estrus were originally devised to decrease the time spent detecting estrus; however, systematic breeding programs are now being used for convenience and efficiency in reproductive management. Systematic breeding programs provide an organized approach for administering artificial insemination (AI) at first service. Moreover, reproductive management is based on a methodical approach for the entire herd rather than for the individual cow. Targeted BreedingTM (Pharmacia-Upjohn, Kalamazoo, MI) consists of a series of three PGF2
injections at 14-d intervals. For convenience, injections are usually given one day a week to all cows that surpass the specified target date. The PGF2 injections may be continued until detection of estrus and AI or fixed-time AI. Ovsynch consists of a GnRH injection at a random stage of the estrous cycle, followed by PGF2 7 d later, a second GnRH injection 36 to 48 h after PGF2, and timed AI. Research has shown that both Ovsynch and Targeted BreedingTM can improve reproductive performance over that of traditional programs.
Key Words: estrus synchronization • systematic breeding • prostaglandin F2 • gonadotropin-releasing hormone
Submitted on June 24, 1997
Accepted on December 16, 1997
This article has been cited by other articles:
|
|
 |
|
  N. J. Olynk and C. A. Wolf Stochastic economic analysis of dairy cattle artificial insemination reproductive management programs J Dairy Sci, March 1, 2009; 92(3): 1290 - 1299. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Stevenson Progesterone, Follicular, and Estrual Responses to Progesterone-Based Estrus and Ovulation Synchronization Protocols at Five Stages of the Estrous Cycle J Dairy Sci, December 1, 2008; 91(12): 4640 - 4650. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. J. Olynk and C. A. Wolf Economic Analysis of Reproductive Management Strategies on US Commercial Dairy Farms J Dairy Sci, October 1, 2008; 91(10): 4082 - 4091. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Stevenson, D. E. Tenhouse, R. L. Krisher, G. C. Lamb, J. E. Larson, C. R. Dahlen, J. R. Pursley, N. M. Bello, P. M. Fricke, M. C. Wiltbank, et al. Detection of Anovulation by Heatmount Detectors and Transrectal Ultrasonography Before Treatment with Progesterone in a Timed Insemination Protocol J Dairy Sci, July 1, 2008; 91(7): 2901 - 2915. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. P. Meyer, R. P. Radcliff, M. L. Rhoads, J. F. Bader, C. N. Murphy, and M. C. Lucy Timed Artificial Insemination of Two Consecutive Services in Dairy Cows Using Prostaglandin F2{alpha} and Gonadotropin-Releasing Hormone J Dairy Sci, February 1, 2007; 90(2): 691 - 698. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. D. Peeler, R. L. Nebel, R. E. Pearson, W. S. Swecker, and A. Garcia Pregnancy Rates After Timed AI of Heifers Following Removal of Intravaginal Progesterone Inserts J Dairy Sci, September 1, 2004; 87(9): 2868 - 2873. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B.-A. Tenhagen, M. Drillich, R. Surholt, and W. Heuwieser Comparison of Timed AI After Synchronized Ovulation to AI at Estrus: Reproductive and Economic Considerations J Dairy Sci, January 1, 2004; 87(1): 85 - 94. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
