Four measurements of feeding behaviour of the domestic cock were made in a standard situation after the birds had been deprived of food for 2, 24 and 48 hr. These were amount consumed, rate of food consumption, rate of pecking and strength of pecking. When the food offered was in mash form, there were no differences between the birds' scores in these measurements in the tests after 24 and 48 hr deprivation. However, after these long deprivation schedules their scores for the amount eaten, pecking rate and rate of consumption were significantly different from those in the 2-hr deprivation tests. When food of identical nutritive value was offered in the form of pellets the birds ate more and their pecking rate was higher after 48 hr than after 24 hr deprivation.