THE PRE-FARROWING BEHAVIOR OF SOWS WITH OPERANT ACCESS TO SPACE FOR LOCOMOTION

It has been shown previously that sows perform more locomotion on the day prior to farrowing than on preceding days. If the sow is motivated to perform locomotion in this period then confinement in a farrowing crate prior to farrowing may be detrimental to her welfare. An operant conditioning technique was used to examine the motivation of the sow to gain access to space to perform locomotion. Six sows were observed in a 6.5 m X 7 m test arena with a 2 m X 2 m pen in one corner from 4 days before parturition was due until farrowing occurred. The sows wer e required to lift a lever on a progressive ratio to move from the sma ll pen to the test arena, and again to return, The ratio of lifts reac hed during the day before farrowing was significantly higher than that reached on previous days (P < 0.01) and the sows showed an increase i n locomotion on the day prior to farrowing compared to preceding days (P < 0.05), despite the operant requirement on access to space. The ef fect of the introduction of the operant on the expression of locomotio n is discussed.