Boar behaviour complex, but increasingly well understood

Light influence, group size and pen layout are nil.

Boar behaviour and the factors that influence it are increasingly well understood. Boars can cause restlessness by fighting and mounting each other. It is important for pig farmers to know which factors can positively or negatively influence this behaviour. The Dutch Product Board for Livestock, Meat and Eggs and the Ministry of Economic Affairs therefore assigned the VIC (Swine Innovation Centre) in Sterksel to study whether light, group size and a hiding wall in pens influence boar mounting behaviour. The study was carried out by Wageningen UR Livestock Research.

The researchers monitored pigs while they were exposed to green light or a gradually increasing light regime. The effect of lighting proved minimal: the pigs only demonstrated slightly less aggressive behaviour during finishing. Mounting behaviour did not change when the pigs were housed in larger groups (24 animals in a pen instead of 12). A hiding wall in pens also did not reduce mounting behaviour. Finally, the researchers concluded that mounting behaviour occurred less at night than during the day and less in the mornings than during the afternoons.

Behaviour influencing factors
Studying factors that influence boar behaviour is complex. Cataloguing the factors light, group size and pen size/layout made new information available on boar behaviour. The past year at 70 pig farms behavior observations were conducted. The researchers will further analyse the results of these practical trials.

The full results are described in the report “Effect van licht, groepsgrootte en schuilwand op gedrag van beren” [The effect of light, group size and hiding walls on boar behaviour].

Additional information can be obtained from researcher Carola van der Peet-Schwering (