The temporal relation between the luteinizing hormone (LH) surge and the occurrence of two components of sexual behavior was investigated in female goats. Behavior observation and blood sampling were carried out every 2-6 hr from 26 hr before through 116 hr after prostaglandin (PG) administration which was given to induce luteolysis during the mid-luteal phase. The preovulatory LH surge appeared 30-100 hr after PG injection, and it continued for 6.5 +/- 0.4 hr. Although the interval from PG injection to the onset of the LH surge differed considerably among individuals, the proceptivity (defined as an approach to a male with vigorous tail-swishing) and the receptivity (defined as an acceptance of male's mounting or copulation) occurred well synchronized with the LH surge in each female. The proceptivity and receptivity were observed from -7.4 +/- 1.7 hr to 16.8 +/- 1.5 hr and from -2.6 +/- 1.6 hr to 13.0 +/- 2.0 hr, respectively, with regard to the LH surge onset (0 hr). Thus the proceptivity appeared first and lasted longest, and the receptivity was always seen around the time of the LH surge suggesting an existence of causal relationship between these two preovulatory events. The present results support the view that the female goat has evolved an efficient behavioral strategy such that it actively attracts males before it becomes fully receptive of male's approach to mate, when the LH surge occurs simultaneously to ensure a high conception rate at the subsequent ovulation.