Measurement of temperament in pigs

The original concept of temperament arose from studies on aggression in house mice selected from two genetically diverse lines of mice; the first line showing strong avoidance behaviour in response to attack while the second line did not react as readily to aggressive behaviour. When male mice from these two different lines were placed in a cage in which a resident was living, the animals displaying a marked avoidance response and spent a lot of time in fleeing behaviour whereas the low responsive animals spent most of their time immobile (Benus et al., 1991). This led these authors to classify the two coping strategies as active and passive respectively.