Stockperson-directed aggression by the sow is a potential problem in open farrowing systems, but may have advantages for piglet survival. The aims of this study were to compare the levels of aggression exhibited in open and confined farrowing systems and to determine whether there was any relationship between aggression in the farrowing house, the responses of the sow in a human approach test during gestation and piglet survival.

A total of 62 LW x Landrace gilts (PIC, Abingdon, UK) were subjected to a standard approach test, followed by a test in which the experimenter approached the pig. At testing, approximately 6-8 weeks prior to parturition, each group of 3-5 gilts was moved to a handling area. Here, each gilt in turn was fitted with a heart rate monitor and moved to a 2.4m x 2.4m test arena. After 2 min acclimatisation, an unfamiliar experimenter entered the pen and stood for 3 min against one wall. After this, the experimenter approached the gilt and touched her on the snout. Behaviour and heart rate were recorded continuously.