Feeding of sows without confinement of the sow during feeding

The study investigated the behaviour of breeding sows fed by an electronic feeding system in which the sow is not protected from its pen mates during feed intake.Three feeding stations were installed for a dynamic group of a maximum of 36 sows (maximum animal/feeding place ratio: 12:1). The sows’ behaviour at the feeding stations was observed on six days in intervals of three weeks. The following behavioural patterns were recorded: “aggressive interactions with retreat” and “aggressive interactions without retreat”. In addition, the feeding computer recorded how much time the sows spent in which feeding station and differentiated whether food was distributed or not.On average, each sow visited the feeding stations 55.6 times per day with feed intake and 99.9 times per day without feed intake. Displacements of sows at the stations were accordingly frequent. An average of 16.6 incidences of “aggressive interactions with retreat” and 3.6 incidences of “aggressive interactions without retreat” were recorded per sow and day. Not all animals displaced the other animals from the feeding stations with equal frequency. Especially high-ranking sows often visited the feeding station without feed intake, thereby displacing the feeding sow from the station.The results show that restricted feeding of breeding sows in electronic feeding systems without confinement of the sow during feeding is problematic in terms of animal welfare. Especially low ranking sows are frequently displaced form the feeding station.