When the plan goes awry: how to negotiate estrus synchronization errors in beef cattle

Estrus synchronization protocols vary widely, and errors during implementation are not uncommon. When an error is made, recommendations for resolution must consider the initial purpose of implementing the synchronization protocol in the herd. The ideal solution is to convert the protocol to a different published protocol. When this is not possible, the safest solution for maintaining an acceptable pregnancy rate is often either restarting a synchronization program or potentially foregoing artificial insemination for the season. Knowledge of estrous cycle physiology and how hormone treatments manipulate the cycle are foundational when attempting to modify a protocol based on the specific error that is made. Errors made early in a synchronization protocol tend to be more manageable than those made toward the end of the protocol. The use of less valuable semen and immediate introduction of a clean-up bull should be considered to maximize pregnancy outcomes when attempting to correct an error during estrus synchronization.