A cow or heifer is said to bull when she enters the active phase of estrus and becomes receptive to breeding. Handlers look for physical indicators like restlessness, clear mucus discharge, and standing to be mounted by other cattle. Identifying exactly when a cow begins to bull dictates the timing for successful artificial insemination or pasture breeding.
Heard on the job
Watch that black heifer in the lower pen, she started bulling this morning and needs to be bred tonight.
Insider tip
A cow that frequently bulls but fails to settle after multiple breedings is usually culled from the herd.