Effects of social isolation and social separation in domestic chicks.

Conducted 2 experiments with 60 white Leghorn chicks, with subsamples of 24 and 36 animals tested in 2 independent replications, to assess the impact of early social isolation and social separation on the behavior of domestic chicks. In Exp I, a 3-wk longitudinal study, the day-to-day behavior of isolated chicks was compared to the behavior of birds housed in pairs. Ss in a 3rd group were reared in pairs for 2 wks, and then were permanently separated. The daily observations of all Ss recorded disturbance reactions, exploratory activities, consummatory behavior, grooming, and inactivity. In Exp II, 36 Ss from the 3 experimental conditions were tested in the 4th posthatch week for general social responsiveness in the presence of unfamiliar conspecifics. Results show that (a) both isolation and separation produced behavioral anomalies; (b) separated Ss' reactions indicated patterns analogous to post-separation patterns seen in other species; and (c) the effects of isolation and separation were not qualitatively equivalent--exposure to conspecifics revealed antisocial behavior in the isolates, relative to the responses of their socially reared and separated counterparts. Results are discussed in terms of a model for differences in the essence and consequences of early social isolation and social separation. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)