Association of personality traits with maintenance and social behaviour of rams (Ovis aries)

Animal personality is defined as individual differences in behaviour that are consistent over time and in different contexts. Aspects of personality (personality traits) have been identified in previous studies on farm animals indicating that they may affect the individuals' behaviour, dominance rank, coping and cognitive ability and physiology. The aim of the present study was to identify whether rams (Ovis aries) reared under an intensive farming system, present personality traits and if these traits are associated with the behaviour of individuals under different contexts, to gain a better understanding on sheep personality and the consistency of behaviour within individuals. Adult rams (N = 13) reared under an intensive system were observed during three different periods (A, B, C). At period A rams formed one stable group of eight individuals. Period B started when five rams entered the group simultaneously and period C when rams formed one stable group of 13 individuals. Scan sampling was used to record if and with whom each individual was in proximity. All social behaviours between individuals were collected ad libitum and maintenance behaviours were scored using focal sampling. The study demonstrated two personality traits, namely Dynamic and Receptive, as the two aspects of rams' personality (KMO = 0.667; p < 0.01). Dynamic behaviour was correlated with frequent vocalizations (rs = 0.586, p < 0.05) while receptive behaviour was correlated with increased time lying (rs = 0.593, p < 0.05). Furthermore, an association was noted between individuals' personality scores and social behaviour (p < 0.05), indicating that dynamic individuals appeared to perform more agonistic behaviour (p < 0.05) and receive more submissive (p < 0.01), within the examined periods.