Responses to successive test of induction of maternal behaviour in hens

This experiment was undertaken to find out if the kinetics of the behaviours which emerge gradually during a first experiment of maternal induction was modified by a second and then a third similar experiment, or not. In addition, during the second experiment the behaviour of experienced hens was compared to that of naive hens of the same strain undergoing their first induction. Three important facts appeared : (i) In each series, maternal behaviours (accepting contact of chicks, clucking) emerged gradually (significant day effect). (ii) Repeating these experiments revealed on the whole neither increase nor decline of hens' responsiveness towards chicks (negligible series effect). No significant difference between naive hens and hens having already had a first induction experience was found. (iii) There was an important difference between hens concerning their delay in adopting, and a good stability of individual profiles was found between series (significant hen effect).