Campo, J. L., Gil, M. G., Dávila, S. G. 2005. Effects of specific noise and music stimuli on stress and fear levels of laying hens of several breeds. Applied Animal Behaviour Science 91(1-2), 75-84.

The results of the present study indicate that specific noise stimulus (90 dB versus 65 dB) causes stress and fear in laying hens and specific classical music stimulus (75 dB versus 65 dB) has a negative influence on their fearfulness.