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The effects of type of housing (stalls versus pens) and method of heat detection (fence-line boar exposure conducted in-place versus after relocation of gilts to the boar room) on the accuracy and rapidity of estrus detection were evaluated in 24 gilts during two successive estrous periods. Gilts relocated to the boar room showed a higher rate of estrus detection and a more rapid estrous response (P < .05) to fence-line boar exposure (81% and 1.7 min, respectively) than gilts provided fence-line boar exposure in-place (67.5% and 2.3 min, respectively). Gilts housed in stalls and pens showed similar rates of estrus detection (68% and 67%, respectively) but the estrous response to fence-line boar exposure tended to occur more rapidly in gilts housed in pens than in stalls (2.0 versus 2.5 min, P < .1). Gilts not detected in estrus with fence-line boar exposure were slow to respond to a later heat check with physical boar exposure (3.8 min). Physical boar exposure is required for highly accurate heat detection in gilts. For optimal results, boar stimulation should be provided in an environment removed from the residence of the gilts.