Welfare-improving enrichments greatly reduce hens' startle responses, despite little change in judgment bias.
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ABSTRACT:
SUBMITTER: Ross M
PROVIDER: S-EPMC6695442 | biostudies-literature | 2019 Aug
REPOSITORIES: biostudies-literature
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Welfare-improving enrichments greatly reduce hens' startle responses, despite little change in judgment bias.
Ross Misha M Garland Anna A Harlander-Matauschek Alexandra A Kitchenham Lindsey L Mason Georgia G
Scientific reports 20190815 1
Responses to ambiguous and aversive stimuli (e.g. via tests of judgment bias and measures of startle amplitude) can indicate mammals' affective states. We hypothesised that such findings generalize to birds, and that these two responses co-vary (since both involve stimulus evaluation). To validate startle reflexes (involuntary responses to sudden aversive stimuli) and responses in a judgment bias task as indicators of avian affective state, we differentially housed hens with or without preferred ...[more]
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