Cognitive bias testing offers a promising method for assessing the emotional states of pigs on commercial farms, measuring whether animals interpret ambiguous stimuli optimistically or pessimistically.
Cognitive bias testing represents a methodological advance in animal welfare science that moves beyond behavioral and physiological indicators toward direct assessment of animals' subjective emotional states. The ability to determine whether pigs on a farm are experiencing their world more optimistically or pessimistically has profound welfare implications: it provides a measure of how animals feel that is more directly relevant to their subjective experience than injury rates or cortisol levels alone. Research consistently shows that enriched environments produce more optimistic cognitive biases in pigs — suggesting that the behavioral indicators of welfare we already use map onto real differences in subjective experience. For commercial farm welfare assessment, validated judgment bias protocols could provide auditable emotional welfare measures that go beyond current physical health and behavior-based indicators. This would represent a significant advance in the rigor and relevance of welfare certification.