Groups of end-of-lay (spent) hens were subjected to three different treatments on a short flat-belt conveyor. Observations of bird behaviour indicated that the incidences of wing flapping, loss of balance and alarm calling significantly increased when birds were conveyed up and down
slopes in comparison to being conveyed horizontally (P<0.01). Birds were significantly more hesitant when approaching the incline compared to the horizontal (P<0.001). However, differences in behavioural responses were not reflected in times spent in tonic immobility or open-fteld tests.
There were no significant differences for the three treatments. It is possible that human contact, before and after conveying, was a more significant fear stimulus than the treatment itself.