Background & Aims

Play behaviour, despite being a widespread phenomenon among animals, still leaves several questions unanswered, related to what purpose it serves, and how it originated and evolved. Playfulness tends to increase in occurrence in domesticated animals, in comparison to their wild ancestor, thus making play a key behavioural trait for studies on domestication effects.

All domesticated chickens originate primarily from the Red Junglefowl. Behavioural differences due to domestication effects have been studied previously in chickens, by comparing domesticated layers and wild Red Junglefowls. That chickens perform what are considered to be play behaviours is established. However, the amount of research conducted on play behaviour in chickens is limited, and how this phenotype was affected by the process of domestication is unknown for the species.

The aim of the present study was to investigate if and how the domestication process has influenced play behaviour in chickens, by comparing its occurrence in the wild Red Junglefowl and the domesticated White Leghorn. An additional objective was to characterise play in chicks by studying the ontogeny of play behaviour.

To the best of our knowledge, this is the first study systematically comparing domestication effects on the ontogeny of play behaviour in chickens, or any species.