AVERSIVENESS OF MECHANICAL CONVEYING TO LAYING HENS

1. Passive avoidance was used to investigate the aversiveness to layin g hens of the sound and motion associated with travel on a short secti on of flat-belt conveyor. 2. Three groups of 7 birds were trained to k ey-peck for food at an operant panel and then exposed to a passive avo idance schedule in which the treatment stimuli were activated by key-p ecking. 3. Birds exposed to both sound and motion (SM), or sound only (S) showed significantly greater suppression in key-pecking than birds in the control group (C) which had not been exposed to either stimulu s. No significant difference was found in aversion levels between the S and the SM groups. 4. Sound alone appeared to be as aversive as soun d and motion combined, although certain caveats to this conclusion are given.