Executing specific foraging behaviours does not represent a general goal state of foraging in dry sows (Sus scrofa)

Intensively housed domestic pigs (Sus scrofa) have little opportunity to perform diverse foraging behaviour though they still seem strongly motivated to do so. Here, we investigated whether the execution of specific behaviours may in itself satisfy their foraging motivation. We elicited the specific foraging behaviours rooting, grazing, and biting & chewing by providing 24 dry sows with three different substrates. Sows visited three pens consecutively. Two of the three substrates were offered one in pen 1 and the other in pen 2, whereas pen 3 provided the three substrates simultaneously. In the control condition, all three materials were provided in all pens. In pen 1 and 2, the sows predominantly showed those foraging behaviours that were to be elicited by the specific substrates. Sows spent less time in pens with a single substrate compared with when all substrates were available. Moreover, durations of the specific behaviours which had not been performed in pen 1 and 2 increased in pen 3. Finally, the lowest proportion of time was spent in pen 3 in the control condition. In conclusion, the results indicate that performing single behaviours of the foraging repertoire did not satisfy the sows' overall foraging motivation.