We need to improve our understanding of the factors that are important for the control of food intake on high bulk foods. The study of short term feeding behaviour (STFB) may help to do this. The objective of this experiment was to study the effects of giving foods differing in bulk content on the STFB of growing pigs. It was expected that the foods would result in different levels of daily intake and that this would be reflected as differences in STFB between the foods. Two hypotheses were developed based on ideas about the way in which a physical constraint to intake could arise. H1; there would be less diurnal variation in feeding on high bulk foods that limit intake. H2; feeding patterns on bulky foods would be less flexible than those on a control food when feeding time is limited by reducing time of access to the feeder.