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Copyright © 2015
Angus Journal

Experiences with Fixed-Time AI

by Meghan Richey for Angus Productions Inc.

“All estrus synchronization systems work, but none has worked as well for us as fixed-time artificial insemination (AI). In terms of the cost, the results and my time input, it offers us the best solution,” said Mike Kasten, 4M Ranch, Millersville, Mo. He shared his experience with synchronization and AI at the Applied Reproductive Strategies in Beef Cattle symposium Jan. 29. The workshop was hosted in conjunction with the 2010 Cattle Industry Annual Convention and NCBA Trade Show in San Antonio, Texas.

Mike Kasten

"You have to trust the system and stick to the protocol, especially knowing what we know now about how many females don't exhibit heat. We don't heat detect at all anymore," Mike Kasten said.

The number of times cows go through the chute seems to be a major sticking point for a lot of people in selecting a synchronization system, Kasten observed, so he started recording the actual time spent on each female. Cows make three trips through the chute, with a total of 10 minutes spent hands-on. Heifers make four trips through the chute, with a total of 11.2 minutes spent hands-on.

“Considering we get up to 80% success rate with the cows and 60% success rate with the heifers, that’s a time investment I’m willing to make,” Kasten said.

The timing of the system is both its biggest blessing and curse. Kasten says the biggest economic benefit is that they have achieved a 65-day calving season. However, the most challenging aspect of the system is that you have to be 100% committed to the rigid time schedule.

And you have to trust that it works. “Don’t get stupid and start ignoring the protocol,” he advised.

“How many times have you heard someone say, ‘We didn’t see many of them in heat so we didn’t want to waste the semen,’? I have news for you people: Do you really think you’re going to get more females bred by leaving the semen in the tank rather than putting it to work? You have to trust the system and stick to the protocol, especially knowing what we know now about how many females don’t exhibit heat. We don’t heat detect at all anymore,” he said.

Fixed-time AI is the best tool for a commercial cow-calf producer, Kasten said. “It gives you access to genetics that are pretty much guaranteed to improve your herd. There’s real money to be made in premiums if you improve your genetics with AI.”

There is wide variation in conception rates among AI bulls, even among the top-name bulls, he cautioned. “Be sure to ask your semen rep which bulls work in a fixed-time AI system. Then choose your EPD profiles from those suggestions.”

Click here for speaker's PowerPoint. (72 KB pdf)
Click here for speaker's proceedings. (136 KB pdf)
Click here for audio to presentation. (4.2 MB mp3)

The ARSBC program was developed by the Beef Cattle Reproduction Task Force to improve understanding and application of reproductive technologies, including AI, estrus synchronization and factors affecting male fertility. For additional coverage — including summaries, proceedings and audio for each presentation — visit the newsroom at For API coverage of the Cattle Industry Convention, visit the newsroom at

Editor’s Note: This article is available as a news release to redistribute per an agreement between the symposium hosts and Angus Productions Inc. Click here to submit a request for a high-resolution photo of the speaker.