The effects of imprinting stimulus availability and temperature on vocalization and motoric behaviors of the neonatal domestic chick

Abstract

Each of 32 neonatal White Leghorn chicks (Gallus gallus domesticus) experienced each of the four environmental situations and motoric and vocal behaviors were observed. The four environments were derived from a 2 X 2 (stimulus availability X temperature) factorial design. The levels of stimulus availability were either present (visible) or absent (not visible) while the two temperature levels were 32.5°C or 18°C. A factor analysis of the observed behaviors yielded six factors; three of which concerned motoric behaviors and three of which concerned vocalizations. A 2 X 2 (stimulus availability X temperature) within subjects analysis of variance for each factor was also performed. These results show that motoric behavior was largely affected by the availability of the imprinted stimulus. Results from the vocalization factors revealed one factor comprised of twitter calls, a second factor comprised of peep calls and a third factor comprised of calls that sonographically resembled an intermediate call. The analysis of variance on these factors revealed that the situational occurrence of the intermediate call factor resembled neither of the other two, more traditional, vocalization categories.