Does occasional movement make pecking devices more attractive to domestic chicks?

Abstract

1. Previous studies have shown that a bunch of string is a particularly attractive pecking stimulus for chicks and adult laying hens. Because movement is thought to be an important attribute of enrichment objects, this study determined whether occasional movement would affect the attractiveness of this device. 2. In experiment 1 the responses of pair-housed chicks to string were compared when devices in adjacent cages were either linked (so that pecking or pulling at the string in one cage moved the adjoining one) or not (separate). In experiment 2 the devices in half the cages were jigged remotely by the experimenter whereas the others remained static. In both cases, the string devices were introduced into the cages for 10 min on each of 5 consecutive days. 3. No treatment effects were apparent in experiment 1 when pooled data was analysed but comparison of responses on days 1 and 5 revealed that only the chicks presented with non-linked devices showed increased interest with repeated exposure. 4. Chicks given static devices in experiment 2 pecked sooner, more often and longer at them than did those exposed to similar ones that were jigged regularly by the experimenter. Jigged devices attracted slightly more pecking with repeated exposure, which may have reflected familiarityinduced fear-reduction, but chick responses showed no apparent changes from day 2 onwards. Conversely, rather than showing habituation, the chicks pecked progressively more at the static devices with repeated presentation. 5. The present results show that chicks pecked readily at bunches of white string, thus confirming its attractive properties but that static devices were more attractive than those incorporating occasional movement. These and previous findings are discussed in terms of their implications for the development of effective environmental enrichment.