The means of various estrous characteristics followingPGF2administration during the early or late luteal phasein buffalo heifers (n = 50) and the distributions for thebeginning of estrus and ovulation are described in Table 1and Fig. 1, respectively. The intervals between PGF2administration and the beginning of synchronized estrusand between PGF2administration and ovulation wereshorter (P < 0.05) for heifers treated during the early lutealphase compared to the late luteal phase (Table 1 andFig. 1). However, there was no impact (P > 0.05) of PGF2administration during the early or late luteal phase on theduration of estrus, the interval between the beginning ofestrus to ovulation, the interval between the end of estrusto ovulation and the maximum diameter of the ovulatoryfollicle