Beattie, V. E., Sneddon, I. A., Walker, N. 1993. Behaviour and productivity of the domestic pig in barren and enriched environments. In: Livestock Environment: Fourth International Symposium. 42-50. American Society of Agricultural Engineers, St Joseph, Michigan.
It was shown that pigs housed indoors and given a substrate [peat] to root, increase the amount of time spent exploring and decrease the time spent inactive and in behaviour directed towards their pen-mates such as chewing ears and tails.
Year
1993