Human contact and feeding as rewards for the lamb's affinity to their stockperson

Abstract

In this paper, we assessed the relative importance of handling and feeding lambs in the development of affinity for their stockperson. We also tested the extent to which this affinity can be linked to feeding motivation and behaviour in a conditioning hypothesis. Lambs were reared in groups of three and artificially fed from a multiple-nipple bucket. From the first day of age, contacts with the stockperson were given in the home pens three times a day for 5 consecutive days, then 2 days a week until the tests. In five groups (Presence), the stockperson sat motionless; in five groups (Handling), he caught the lambs and stroked them; in six groups (Handling & Feeding), he caught and stroked the lambs while placing them at the food bucket. At 3.5 weeks of age, the lambs were individually tested in a 6 m × 1.5 m arena. In Test 1 (Human Test), the lambs stayed 2 min alone, 2 min with the familiar stockperson, then 2 min alone again. In Test 2 (Bucket Test), a milk bucket was added to the arena and the same procedure was followed. For each test, the lambs were observed after 5 h of starvation or ad libitum feeding (cross-over design). In the Human Test, Presence lambs spent less time near the stockperson (27 ± 7 s) than Handling lambs (59 ± 9 s, P = 0.03) or Handling & Feeding lambs (59 ± 6 s, P = 0.03). In the Bucket Test, three lambs suckled from the bucket. Only Handling & Feeding lambs increased their time spent near the bucket when the stockperson entered (treatment x time, P = 0.05). No interaction between the treatments and the hunger state was observed in any test. Handling per se contributed to the development of lambs’ affinity for their stockperson during individual tests, and could have calming and rewarding properties for the lambs. Neither feeding from a bucket during handling nor hunger state increased this affinity. Nevertheless, some association of the stockperson with the milk bucket seemed to occur, suggesting a food conditioning. The way of feeding the animals and their perception of the test as an alimentary situation are discussed.