Testosterone and isolation effects on open-field behavior in male chicks.

The behavioral differences between control and testosterone-treated male chicks reared either in group or singly, then exposed to the open-field test have been analyzed. Motor activity and vocalization are definitely enhanced by isolation in singly reared testosterone treated chicks, whereas this effect is less evident in untreated chicks. Some interaction between isolation and hormone treatment was evidenced, since in group-reared chicks testosterone treatment does not seem to influence the above behaviors significantly, as it does in singly reared chicks.