Can tail-in-mouth behaviour in weaned piglets be predicted by behaviour and performance?

P was born significantly smaller than R, but the difference had disappeared at 4 weeks. Growth or sex distribution did not differ between categories. Category differences in performed behaviour were evident at 4 weeks of age, when P showed more overall activity and environmental exploration as compared to R, as well as more bouts of tail-nosing than N. Different aspects of behaviour changed in the different categories between 4 and 9 weeks of age. In P social activity increased significantly and went from no preference at 4 weeks to a significant preference for social actions for R over N at 9 weeks. N was socially passive at 9 weeks while receiving more social behaviour than the other categories. These differences in behaviour suggest that the categories represented different phenotypes of pigs.