Agonistic behaviour in grouped sows. II. How social rank affects feeding and drinking behaviour

Groups of sows housed in pens with concrete floor were observed to detect differences in feeding and drinking behaviour between animals of high- and low-rank. Dominant individuals remained at the centre of the mash pile defending the food against other animals. The total time spent feeding was similar in high- and low-ranking sows. However, the high ranking sows interrupted feeding more often; subordinates stopped feeding for longer periods because they retreated from attacks. As the mash began to disappear the low-ranking sows resisted the dominants' attacks and refused to leave the feeding area. Drinking behaviour was very frequent in subordinate sows in the early minutes of the meal; this is probably a redirected behaviour resulting from the frustration of being not able to feed continuously.