A series of 72-h video studies investigated the behaviour of sows using a computer-controlled electronic identification and feeding system in relation to feed station design. A Pig Code double-entry feed station was modified to provide an optional forward exit on one side, while sows on the other side continued to reverse out. Two groups of 19 sows used each side in turn and their behaviour was recorded after a period of adaptation. Sows given the opportunity used the forward exit on nearly all occasions, unless it was blocked by another animal. A forward exit resulted in more station visits daily (7.2 vs. 4.6, P < 0.001), but non-feeding visits were of shorter duration so that total occupation time was similar (24.4 vs. 26.5 min per sow). Sows learnt to circumvent the computer-controlled mechanism locking the rear gates and showed aggression towards animals in the station. This behaviour had not been observed in the previous 28 months of study. A subsequent study of 39 sows using a single station, where the rear gate and forward exit were both operated mechanically by the sow, showed a mean daily occupation time of 29.7 min per sow in 3.9 visits. A forward-exit station with positive closing of the rear gate is desirable, but some problems with station design remain to be solved. © 1988.
Edwards, S. A., Armsby, A. W., & Large, J. W. (1988). Effects of feed station design on the behaviour of group-housed sows using an electronic individual feeding system. Livestock Production Science, 19(3–4), 511–522. https://doi.org/10.1016/0301-6226(88)90016-4