Data from: Pain and pessimism: dairy calves exhibit negative judgement bias following hot-iron disbudding

However, limited research has examined how pain states affect cognitive processes in animals. Here we present the first evidence of cognitive bias in response to pain in any non-human species. In two experiments, dairy calves (n = 17) were trained to respond differentially to red and white video screens and then tested with unreinforced ambiguous colours in two or three test sessions before and two sessions after the routine practice of hot-iron disbudding.

After disbudding calves were more likely to judge ambiguous colours as negative. This ‘pessimistic’ bias indicates that post-operative pain following hot-iron disbudding results in a negative change in emotional state.

Usage notes

Calf approach responses in the cognitive bias task Calf approach responses to each screen for each session before and after disbudding (%). Approach responses have been averaged across trials (23 each of positive and negative screens; 5 of each ambigous screen) within each session DRYAD_Table 1_Calf responses.docx