Table 1 summarizes the statistics of relative frequency (%) of observed behavior by stalled pregnant females and subsequent reproductive performance. Of 609 observed females, only 20 females (3.3%) showed 5.4 ± 1.02% of 6 h in bar biting, 51 females (8.4%) showed 4.9 ± 0.34% of the 6 h in drinker play, and 395 females (64.9%) showed 19.6 ± 0.82% of the 6 h in vacuum chewing. Figure 1 shows the frequency distribution of vacuum chewing (%) in the 609 females. Subsequent performance measures were extracted from a recording system. The overall farrowing rate was 84.4% with 514 farrowed females of 609 mated females (Table 1). Annual culling and replacement rates on this farm were 46.4 and 56.3%, respectively.