Cattle discriminate between individual familiar herd members in a learning experiment

We tested the ability of cattle to discriminate between socially familiar conspecifics in a Y-maze discrimination experiment. The discriminative stimuli were herd members tethered in the Y-maze side arms (stimulus heifers); approach to one of these was rewarded with food and approach to the other was unrewarded, and their positions were randomly swapped. Each of six experimental heifers was subjected to two pairs of stimulus heifers. All subjects reached the learning criterion (19 out of 20 consecutive choices to the rewarded stimulus heifer's position in the Y-maze) with one pair of stimulus heifers. With the other pair, learning was slower and only three of the subjects reached criterion. All heifers that reached criterion chose correctly in at least five additional trials designed to control for cues emanating from the experimenter's behaviour or from the food reward. We conclude that cattle can discriminate between individual familiar conspecifics, that they can learn discrimination tasks quickly, and that speed of learning and level of correct response can be influenced by the identity of the stimulus individuals. We also explored the experimental heifers' behaviour during the learning process. Behaviours indicative of agitation were observed more often in the second task than in the first and also increased with time during learning tasks (P < 0.05), but were not related to whether a heifer made a correct choice. Head orientation predicted the correct direction when this was subsequently chosen (P < 0.05), whereas body orientation tended to predict the correct direction when the incorrect arm was subsequently chosen (P = 0.063). (C) 2003 Elsevier Science B.V. All rights reserved.