Sociability is defined as the reaction to the presence or absence of conspecifics and the motivation to associate with them. Research on sociability has long been overlooked compared to other personality traits, thus limiting our understanding of behaviours and dimensions which could potentially represent it. We aimed to investigate sociability in real vs. artificial testing conditions.

We developed a Novel Peer Test (NPT) on 80 domestic pigs (Sus scrofa domesticus) to investigate sociability. Each pig was confronted with an unfamiliar conspecific, separated by a fence in a familiar environment. To validate the NPT, we performed classic personality tests, including an Open Field Test, Novel Object Test, Human Approach Test, all repeated after two weeks. Through Principal Component Analysis, we found that the NPT may distinguish pigs’ motivation to interact with a novel conspecific that is independent from novelty seeking, thus it is a promising test for the study of sociability. We also used Social Network Analysis on the social behaviours between pen-mates and showed that the personality tests did not reflect pigs’ social positions in their group.

Thus, sociability may be multidimensional as individuals behave differently when interacting with a novel individual compared to a familiar one. This could have potential implications for the welfare of animals under human care, as their social interactions are often neglected during management practices.