Predatory overtones of open-field testing in chickens

Abstract

Based on a modelwhich holds that open-field behavior is due in large part to an interaction between social separation and the threat of predation, seven experiments were conducted to examine the relationship between tonic immobility and open-field activity in chickens. The results showed that placement in an open field prior to testing for tonic immobility reliably enhanced the duration of immobility. Similarly, procedures that have been shown to modify the length of the immobility episode had a comparable effect on the timing of activity onset in an open field. Since tonic immobility has been independently implicated as a putative predator defense, the correspondence between open-field behavior and tonic immobility was taken as indirect support for the hypothesis that open-field testing contains overtones of predation.153

Assessment of fear in adult laying hens: Correlational analysis of methods and measures

“…Similarly, the open-field and TI responses of domestic chicks are strongly associated (Faure, 1975;Suarez and Gallup, 1981). The present results show that similar relationships exist between the responses of adult domestic fowl to several fear-inducing situations and support the use of the pen with cone, novel rod and tonic immobility tests as methods of assessing fearfulness in laying hens, or at least those of the two behaviourally diverse lines used.…”

Sex differences in the response to social stimuli in young chicks

“…Contrary to a «fear» or «emotionality» hypothesis, GALLUP & SUAREZ (1980) claimed that open-field behaviour may reflect a compromise between opposite tendencies to reinstate social contact with conspecifics and to evade prédation. Indeed, almost all open-field experiments involve (i) predatory overtones related to the human contact resulting from handling associated with removal of the animal from its home-cage and subsequent placement in the testing apparatus (SUAREZ & GALLUP 1981); and (ii) sudden social separation from familiar and/or imprinted companions (SUAREZ & GALLUP 1983, 1985. VALLORTIGARA & ZANFORLIN (1987) suggested than threats of prédation and social isolation may be of different importance in males and females.…”

Open-field behavior of young chicks (Gallus gallus): Antipredatory responses, social reinstatement motivation, and gender effects

“…Gallup and Suarez proposed that, as opposed to a "fear" or "emotionality" hypothesis, openfield behavior might reflect a compromise between opposite tendencies to reinstate social contact with conspecificsand to evade predation. field experiments involve predatory overtones related to the human contact resulting from the handling associated with the removal of the animal from its home cage and its subsequent placement in the testing apparatus (Suarez & Gallup, 1981). Moreover,open-field testing also usually involves suddensocial separation from familiar and/or imprinted companions (Suarez & Gallup, 1983, 1985.…”