EFFECT OF MEAL FREQUENCY AND RATE OF NUTRIENT SUPPLY ON THE POST-FEEDING BEHAVIOR OF THE PIG

There have been suggestions that positive feedback from the meal may s timulate the performance of undesirable behaviour, such as stereotypie s, in the post-feeding period. The aim of this work was to measure the short-term effects of a meal on the post-feeding behaviour of the pig . Pigs (70 kg live weight were offered food ad libitum for 7 days and then given a restricted food allowance for 23 days (experiment 1) or 1 4 days (experiment 2). In experiment 1, the food allowance was given i n one, two or three meals per day. In experiment 2, the food allowance was given in two meals per day and comprised ingredients which suppli ed glucose at different rates (starch, glucose/starch, starch/guar gun ). The pigs' posture and behaviour were recorded in three 1-h periods during the day on 2 days consecutively during the ad libitum feeding p eriod (time period 1) and on pairs of days on three (periods 2, 3 and 4: experiment 2) or two (periods 2 and 3: experiment 2) subsequent occ asions during food restriction. The meal frequency or estimated rate o f glucose supply had no significant effects on posture or behaviour. I n both experiments activity increased with the duration of food restri ction. In periods 1, 2, 3 and 4 of experiment 1, the proportions of ob servations spent were: standing 0.244, 0.260, 0.706 and 0.728 (s.e.d. 0.0346); nosing 0.073, 0.094, 0.229 and 0.253 (s.e.d. 0.0169); rooting 0.032, 0.037, 0.108 and 0.133 (s.e.d. 0.0133). In periods 1, 2 and 3 of experiment 2 the proportions were: standing 0.247, 0.302 and 0.446 (s.e.d. 0.0240); nosing 0.045, 0.075 and 0.138 (s.e.d. 0.0113); chewin g 0.101, 0.126, 0.155 (s.e.d. 0.0121). In experiment 1 feeding rate in creased with duration of restriction (P < 0.001), but was unaffected b y treatment. It is concluded that post-feeding behaviour was influence d more by long-term changes in state (i.e. prolonged food restriction) than by short-term effects of the meal.