Beef Sire Selection and Estrus Synchronization Systems

Dennis L. DeWitt, Livestock Field Specialist, Northwest

Problem Statement:

The prediction of how future progeny of each beef animal is expected to perform relative to the progeny of other animals is expressed in the Expected Progeny Difference (EPD) for specific traits.  Many beef producers do not have the confidence in selecting bulls by EPDs to meet the needs of their beef cow herd.  In addition, there is no question about the benefits of estrus synchronization in improving the cowherd breeding efficiency.  However, navigating the many programs and options that come with estrus synchronization can become an overwhelming and frustrating experience.

Programmatic Response:

The Beef Sire Selection Emphasis Index Module (BeefSIM) was developed by the Iowa Beef Center to allow the beef producer to establish independent selection levels for EPDs based on the needs for their beef herd improvements.  The BeefSIM program allows a producer to find a group of bulls that meet their cow herd needs for genetic improvement. 

The Iowa Beef Center and the North Central Region Bovine Reproduction Task Force developed a spreadsheet program to assist herd managers in making the right management decisions from the 22 synchronization programs available and to establish a program calendar to ensure proper application and appropriate use situations.  This program estimates cost comparisons of systems also.


In the last 2-years spring bull-buying season, 29 different producer bull rankings have been made on over 100 Angus and 35 Red Angus bulls.  The 19 bull buyers utilized the BeefSIM Indexing to purchase 32 bulls for their breeding programs.  They indicated in a one-on-one interview they would not have purchased as many bulls without the confidence of the objective information.  Many of the bulls were not in the top half of the sales and would have been overlooked by the buyers.  The bull breeders were very satisfied in that more bulls were sold at a higher than average price because of the utilization of the BeefSIM program.

The Estrus Synchronization Planner was presented to 34 beef producers and 3 beef agri-businesses.  The 37 persons rated the program extremely useful.  20/37 are using an estrus synchronization system in their operation already.  Two-thirds are planning on using a fixed time AI to save time and costs in the future.  All producers are going to take more care in handling and moving females after AI to increase conception rates.

June 29, 2007
144 Cowherd Enterprise Efficiency


Page last updated: August 2, 2007
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