Deviche P
Z Tierpsychol. 1979 Jan;49(1):77-86. doi: 10.1111/j.1439-0310.1979.tb00276.x.
This experiment was designed to study in male ducklings the behavioural influence of testosterone propionate (= TP) injections, combined with pituitary-adrenal hormones administration, in two test situations: in groups of birds from the same residence cage or from visually isolated cages. It appears from the results that TP administration increased sexual but not aggressive behaviour, while pituitary-adrenal hormones induced very few effects. The responses of the birds were however modulated to a large extent by the type of test situation.