International Journal of Comparative Psychology

Expression of oral stereotypies directed at the drinker (drinking) empty feeder (pecking), by young, caged, restricted-fed broiler breeder fowls, investigated in three experiments in which either the frequency of feeding or meal as varied. Behaviour was measured from regular 15-min videorecordings.  Experiment 1, birds were provided with either one (lA), two (IB) or four meals of 5 g in the morning, and a single balance meal in the afternoon. caused increases in drinking and pecking, compared with lA and IB, but effects meal number and the total weight of food eaten during testing were In Experiment 2, birds were provided with four meals of equal size in the morning,  either 1.5, 1 or 0.5 hr intervals, with a balance meal in the afternoon in the first only. There was no difference among these treatments in drinking or pecking at time, and neither stereotypy responded to variation in inter-feeding interval length the ways predicted by two alternative theoretical models, constructed for from Experiment 1, and a 1 and 2, indicated that both stereotypies were correlated meal size and/or the total amount eaten during testing. In Experiment 3, birds provided with two meals (only) of unequal size at 09.00 and 12.00 h, conditioned to receiving either the large meal (32 g) first, the small meal (8 g) first, and small meals in random order. The main finding was that pecking from the first to the third hour after the small meal only when the small meal first, and did not do so after the large meal. This suggests that the rate at stereotyped pecking declines after eating may depend on the amount that is eaten.