Behavioural reactivity testing in sheep indicates the presence of multiple temperament traits

Temperament in sheep is commonly presented as unidimensional, with a ‘nervous’ temperament indicative of fear and reactivity towards humans and novel environments. However, temperament is multidimensional, with some traits expressed only under certain conditions (context-specific). There is evidence that a common temperament test in sheep, the isolation-box (IB), measures level of activity and not fearfulness as intended, and that behaviours measured in the IB test are indicative of different traits. To investigate this, 16 behavioural responses to a human, to being startled, and to confinement (IB test) were measured in 89 lambs, twice, three months apart. Our results agree with previous studies that vocalisations in all tests and locomotion in two, show high repeatability over time. A principal component analysis identified that vocalisations are domain-general, and are indicative of the trait ‘sociability’, however locomotion is context-specific’ and captures the traits ‘exploration-avoidance’, ‘boldness-shyness’ and ‘general activity’. A cluster analysis identified four behavioural profiles that indicate the trait ‘boldness-shyness’ captures reactivity towards humans. This suggests the IB test, which measures ‘general activity’, is unsuitable for measuring reactivity towards humans in sheep, and that when studying the impact of temperament on other factors, multiple conditions should be used when identify temperament traits.