The impact of stall- or group-housing systems on the welfare of the sow during the first pregnancy

The importance of the type of housing on the well-being of the pregnant sow in intensive breeding systems was studied.Two groups of 48 sows, one bred in individual stalls and the other one in groups of 6 animals, were used. Animal performance, behaviour and physiological and sanitary parameters were measured for the two groups of sows.The experiment took place during pregnancy (between one week before the insemination until one week before the presumed date of farrowing). The sows were then transferred to the farrowing room.In the present experiment there was no difference in performance (weight, backfat measurements or reproduction) between the two systems. However, sows in individual stalls showed more stereotypical behaviour and less social interaction than the sows in groups. During the second half of pregnancy, the individually housed sows spent less time lying on their sides than the group housed sows. All these differences disappeared after the transfer to farrowing crates.Physical injuries caused by fighting or the sides of the pens were more numerous for the sows housed in groups compared to sows housed individually. Finally, the basal level of urinary cortisol was much higher at the end of pregnancy in the sows living individually than in group housed sows.These results tend to show that there are advantages and disadvantages in terms of animal welfare for both types of housing.