Development of dustbathing behavior sequences in the domestic fowl: the significance of functional experience.

The development of the sequential structure of dustbathing bouts was studied in domestic egg-layer chicks from hatching until 23 days of age using a first order Markov chain model analysis. Chicks were reared either with access to sand ("sand chicks ") or on a wire floor ( "wire chicks"). All chicks in both groups developed a basic structure of the elements pecking, bill raking, ground scratching, vertical wingshaking, head rubbing, and side rubbing. Nonetheless, there was more cohesion in the bouts of sand chicks than in those of wire chicks: wire chicks had more pauses in their bouts and performed more elements while standing; also, allopecking (feather-pecking) and preening were incorporated into their bouts. We conclude that the basic structure of dustbathing bouts develops even in the absence of functional experience with feedback from sand. However, absence of normal feedback can lead to problems consisting of interruptions and feather-directed behavior.