Is gentling by people rewarding for beef calves?

Petting and brushing, when used in experiments with animals, is often descr ibed as a positive contact or 'gentling'; this classification is based on h uman perception, and fails to consider the animal's perception of such cont acts. This experiment investigated suckling calves' perception of such cont acts with humans by measuring their behaviour towards a familiar stockperso n. A total of 41 beef calves were reared with twice daily sucklings under h uman control. At 1.5 months, they were allocated to one of three treatments . For 5 min a day, 5 days a week for 2 weeks they were socially isolated (t reatment IS, n = 13), or with a stationary stockman who brushed the calf wh en it approached (treatment PR, n = 14) or with a stockman approaching and brushing the calf (treatment BR, n = 14). All of the BR calves accepted bru shing easily within 5 days of treatment. All of the PR calves briefly inter acted with the stockman within 3 days, but by the end of the treatment, non e were interacting with the stockman. Two tests were performed on 2 consecu tive days after the end of the treatments and 1 month later, in the familia r environment of the treatment procedures. The test procedure included soci al isolation (1 min), isolation with the stationary stockman (1.5 min) and isolation with the stockman trying to stroke the calf (1.5 min). Few animal s approached within 2 m of the stockman during the tests and BR calves tend ed to stay more than 4 m away from him (P = 0.1). Just after the treatment period, BR animals allowed more stroking by the stockman (P < 0.01) on the 2 days of tests and were more motionless (P < 0.01) on the first day of tes ting than animals from the two other treatments. On the second day of testi ng, both BR and PR calves were more motionless (P < 0.01) than IS animals. However, all the animals appeared more tolerant 1 month later and no signif icant difference was found at this age. Acceptance of contact such as brush ing or stroking appears to be more the result of a habituation process than one of positive reinforcement. (C) 1998 Elsevier Science B.V. All rights r eserved.