Social dominance relationships and spacing behavior of swine

Dominance ranks were determined within each of eight pens of domestic swine, Susscrofa. Data on spacing and orientation of subjects were obtained from 16 mm time-lapse films and 35 mm overhead photographs with the aid of a digitizer assisted FORTRAN program, DISANGL 2. Dominance orders among subjects were relatively linear and stable. No pattern in pen location preferences (fixed space) was found but there were relationships between dominance rank and portable spacing patterns of the subjects. Distance to a nearest neighbor was the most important variable affecting the orientation of the swine, and the most dominant animal had a lesser tendency to face away from nearest neighbors at any particular distance and a greater tendency to space further from nearest neighbors than was the case for subordinates. The results of this study support the notion that social dominance provides a means by which a possible limited resource, such as personal space, may be differentially allocated to group members.