When Do Mares First Go Into Heat?

Updated December 12, 2023

In this Ask the Vet video, Dr. Gray and SmartPaker Dan discuss the estrous cycle in fillies and mares. Dr. Gray lists the signs that your mare is in heat, shares how old fillies typically are when they first come in season, and advises at what age you should probably start separating the fillies from the colts.

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SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.