Sound avoidance by hens

The study attempted to assess the aversiveness of various sounds by allowing six hens to move to one (or other) end of a chamber to turn a sound off. A number of sounds at varying intensities were used, including intermittent and constant pure tones and a number of taped sounds. Sounds which some hens moved to turn off were high intensity tones (105-110 decibles measured on the A scale (dB(A))), and a number of taped sounds, both animal and machine generated, at 90 dB(A). The technique appears to be reliable in producing avoidance by individual subjects, and it resulted in differential responding to different intensities of the same sound. It seems likely that spending high percentages of the time with a sound off in this procedure indicates that the sound is aversive. Failure to turn a sound off does not, however, necessarily indicate non-aversiveness.