Aversion learning techniques to evaluate dairy cattle handling practices

Fear of humans is a source of stress for Holstein dairy cattle and can resu lt when animals are handled aversively. We used aversion learning technique s to determine which handling practices cattle find most aversive. In an av ersion race, the cows are repeatedly walked down a race and treatments appl ied when they reached the end; the time and force required for cows to walk down the race are measured. The animal learns to associate walking down th e race with the treatment received; if the treatment is aversive, the anima l will take more time and require more force to reach the end of the race t han if the treatment is positive. In experiment 1, 54 cows were assigned to four treatments (hit/shout, brushing, control, and food). Treatments of 2- min duration were applied three times a day for 4 days. Cows on the hit/sho ut treatment took more time and required more force to walk through the rac e than cows on other treatments, while brushed cows took longer to move thr ough the race than cows given food. In experiment 2, 60 cows were assigned to five treatments (electric prod, shouting, hitting, tail twist, and contr ol). Treatments of 1-min duration were applied three times a day for 3 days . Cows on the shout and electric prod treatments took more time and require d more force to walk down the race than cows on the control treatment. In e xperiment 3, thirty-six 1-1.5-year-old heifers were assigned to three treat ments (hand feeding, gentling, or control) applied as in experiment 2. Trea tments did not affect the time or force required to walk down the race. The aversion race successfully discriminated between handling treatments that differ greatly in aversiveness but lacked sensitivity to distinguish betwee n treatments that were similar. Although many procedural factors must be co nsidered, aversion learning techniques are an effective method to determine which handling practices cattle find aversive or rewarding. (C) 2000 Elsev ier Science B.V. All rights reserved.