Extension News

Synching Estrus Cycles Easier With New Advancements


AMES, Iowa -- Advances in synchronizing the beef cow's estrus cycle continue to move forward, and the Iowa Beef Center at Iowa State University has worked to bring these latest efforts to cattle producers. 

More than three decades ago, all producers had to work with were synchronization systems involving feed-based progesterone products and prostaglandin. Today, researchers from the Beef Reproduction Task Force continue to do research trials and develop new and better systems for synchronizing the heat cycle of the beef heifer and cow. 

“These new synchronization systems have led to better artificial insemination (AI) pregnancy rates and less or no labor necessary for heat detection,” said Daryl Strohbehn, Iowa Beef Center beef specialist.

At the January Applied Reproductive Strategies in Beef Cattle meeting in Colorado, the task force introduced a new fixed-time AI protocol called the “5-day CO-Synch + CIDR” for beef cows. This system, pioneered at Ohio State University, is an eight-day program that involves the use of a gonadotropin-releasing hormone injection at the beginning, the CIDR implant for five days and two injections of prostaglandin eight hours apart after CIDR removal. Seventy-two hours after CIDR removal and the first prostaglandin injection, cows are fixed-time inseminated in conjunction with a gonadotropin-releasing hormone injection. 

“This new 5-day CIDR program is exciting because it gives producers a fixed-time AI option for cows that can be completed in just nine days with very good AI pregnancy rates,” Strohbehn said.

Successful results have been observed with the “5-day CO-Synch + CIDR” program in cows with a range of 55 to 80 synchronized pregnancy rates in 1162 cows. 

Applying synchronization systems successfully has been a challenge to many producers; the most significant problem has been getting the dates and timing of the injections and implants done correctly. To assist producers with this problem, the Iowa Beef Center at Iowa State University has provided the beef industry with the spreadsheet software program called “Estrus Synchronization Planner.”

A newly updated 2009 version of the software, product number ESTRUS 0001, contains the most recent recommended protocols and is available from the ISU Extension online store. Cost of the CD is $25 plus shipping and handling. To learn more, go to the Extension online store at www.extension.iastate.edu/store/.

The Iowa Beef Center at Iowa State University in Ames, Iowa, was established in 1996 with the goal of supporting the growth and vitality of the beef cattle industry. It serves as the university’s extension program to cattle producers and is comprised of faculty and staff from ISU Extension and the colleges of agriculture and life sciences and veterinary medicine. Together, the Iowa Beef Center’s members work to develop and deliver the latest in research-based information regarding the beef cattle industry. For more information about the Iowa Beef Center, visit www.iowabeefcenter.org.


Contacts :

John Lawrence, Economics, (515) 294-6290, jdlaw@iastate.edu

Taylor Gerling, Iowa Beef Center, (515) 294-9124, tgerling@iastate.edu

Willy Klein, Extension Communications and External Relations, (515) 294-0662, wklein@iastate.edu