Behavioural effects of ACTH or corticosterone administration to adult male domestic ducks, Anas platyrhynchos L.

Adult male domestic ducks received a daily injection either of 20 IU of long-acting corticotrophin (porcine ACTH) in 0.25 ml of gelatin or of 20 mg corticosterone in 0.4 ml of Tween 80 during 14 successive days. The behavioural performances of these birds were compared to those observed in a Tween 80 injected group. Both hormone treatments induced a stimulation of wing-flappings while ACTH but not corticosterone injections stimulated sexual precopulatory patterns. No definite effect was evidenced either on aggressive behaviour or on social displays. The results are discussed in view of the present knowledge of the relationships between the pituitary-adrenal axis and behaviour in birds.