Fig. 1.

A layout of the test room. The thickened lines indicate the position of the doors. The doors are named according to which compartment they gave entrance to. The route from entering the test room to entering the anticipation compartment was separated from the rest of the test room with wooden partitions. The test room was 3.3 m high and the compartment walls and doors were 1.4 m high, except for the neutral compartment door that was 1 m high. Compartments were made of 15-mm-thick chipboard. During the test for emotional contagion, training and naive pigs could therefore hear and smell but not see each other