Animal interaction and response to electronic sow feeding (ESF) in 3 different herds and effects of function settings to increase capacity

ESF feeding technology is one of the available choices for the group housing of gestating sows. The general objective of this investigation was to study animal interaction and response to ESF feeding in 3 sow herds. The focus was on the effect of the EFS settings used to determine feeder capacity (feed delivery intervals, amount to be delivered, gate management), on animal interactions and attacks at the feeder, and on the occurrence of vulva lesions and skin injuries. More than 50% of the sow visits to the feeder were non-feeding visits, and sows attacking a sow when she entered the feeder were noted in one third of the visits. When changing sows in the feeder, 4-6 sows queued at the entrance gate; it was found that one third of these had eaten previously. Vulva bites were seen in up to one third of the sows; many of these bites were serious, bleeding lesions. Feeder settings which increased the capacity, thus shortening the available feeding time, also resulted in significantly more sow queuing. In addition, the presence of serious vulva bites was more pronounced in the herd with the highest capacity settings. An increase in feed spillage and the presence of unusual bite lesions at the root of the tail were also attributed to settings for higher capacity (shorter available eating times). It was concluded that the biological function (how sows relate to the system) depended very much on the feeder settings.