Identification of behaviour of weaner pigs in the early phase of aggressive interaction for the development of an automatic monitoring system of pig aggression

Aggressive behaviour among pigs results in negative consequences, reducing health and welfare of animals as well as production output of a farm. In order to develop an automatic monitoring system that monitors and controls pig aggression, an experiment was carried out. The aim of the experiment was to analyze sequences in pig aggressive behaviour. 52 aggressive sequences were observed during the experiment in on farm observations. Behaviour that started the aggressive sequences the most often was nose to nose interaction. 22 out of 52 aggressive sequences started with this behaviour. Head to head knocking was classified as a second most frequent starting behaviour with 13 head to head knocks starting aggressive interactions. Nose to nose interaction and head to head knocking behaviours in most cases started aggressive interactions between animals. Automatic detection of these behaviours might allow early detection of aggression among pigs.