Exploring a simplified affective state test in the red junglefowl

Sammanfattning: Affective states of animals are emotions with positive or negative valance. Positive and negative affective states affect animal welfare, and can bias interpretation of information positively or negatively, respectively. Judgement bias tests measure affective states based on responses to ambiguous cues, intermediate to cues with learnt positive and negative outcomes. Responses closer to those of positive cues indicate positive affective state. However, animals need extensive training to learn initial associations to reference cues. Therefore, I here aimed to validate an alternative affective state test based on instinctive avoidance of patterns resembling eyespots. Responses to ambiguous eyespot cues similar to responses to full eyespot cues could indicate negative affective state. To test this, behavioural responses of red junglefowl (Gallus gallus) chicks to ambiguous cues from a validated judgement bias test were compared to responses to cues resembling eyespots. In a second cohort of birds, I developed simplified tests with only one ambiguous cue in each tests. I predicted that responses in both tests would correlate positively. In the original tests, shorter distance and latency to approach ambiguous cues correlated positively with latency to approach one of the eyespot cues, a full eyespot cue. This pattern was only observed in females. In the simplified tests, at 4 weeks of age, shortest latency to approach cues correlated among tests. This pattern was not observed when chicks were tested at 2 weeks of age. Overall, the eyespot test is a promising alternative affective state test, but further studies exploring sex- and age-effects, are needed.