International Journal of Comparative Psychology

The

present study examined the effects of two treatments on the approach / avoidance responses of pair-housed female domestic chicks of a Ross broiler and two laying strains (one docile ISA Brown medium hybrid, one flighty White Leghorn light hybrid) to a visible experimenter. Chicks in the visual contact (VC)group were  allowed to see the experimenter for 30 s twice a day from 1 day of age until testing at 10 or 11 days whereas controls (CON) received minimal human exposure throughout the study. Apart from the visible presence of the experimenter, treatment procedures were similar for the two groups. All chicks were tested individually but pair means were used as data points. Chicks of all three strains which had received the VC treatment showed considerably lower avoidance of humans than did their CON counterparts. The present results demonstrate that fear of humans was markedlyreduced by a simple regime of close visual contact with the experimenter presumably through habituation, and that this effect was common to chicks of flighty as well as docile strains. These findings are discussed in terms of their imphcations for resource management in the laboratory and on the farm.