Preparturient behavior of confined ewes: time budgets, frequencies, spatial distribution and sequential analysis

• Published in: Applied animal behaviour science Vol. 34; no. 4; pp. 329 - 344
• Main Authors: Echeverri, A.C., Gonyou, H.W., Ghent, A.W.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.1992
• Subjects: AUDIOVISUAL AIDS; BEHAVIOUR; BREBIS; COMPORTAMIENTO; COMPORTEMENT; EWES; MEDIOS AUDIOVISUALES; MOYEN AUDIOVISUEL; OVEJA; PARTO; PARTURITION
• ISSN: 0168-1591; 1872-9045
• DOI: 10.1016/S0168-1591(05)80093-0

The objective of this study was to determine and quantify the pattern of behavioral changes which occur prior to parturition in sheep. A total of 15 ewes were observed continually for 12 h prior to lambing using time-lapse video recordings. During observations, ewes were housed in a group of eight in a 2.7 m×8.8 m pen. All observable behaviors were recorded with an electronic event recorder. Time budgets and frequencies of behaviors were determined for each 2 h period. Two event sequences for 20 different behaviors were tallied and pooled across ewes for each period. Spatial distributions of the focal ewe and the group were recorded at 5 min intervals for the 12 h prepartum. Ewes spent more time standing during the final 2 h (78% of total time) than 12-10 h before lambing (48%; P<0.01). Time spent sniffing the ground increased during the final 2 h (30.8%) compared with periods of up to 4 h before lambing (11.8%; P<0.01). The frequencies of several behaviors were greater ( P<0.01) during the final 2 h period than 12-10 h before lambing: active social interactions, passive interactions, standing up, steps taken, ground sniffing, pawing the ground, circling and flanking. The first period in which a significant difference in activity was observed, compared with 12-10 h prepartum was 8-6 h for time spent standing, 6-4 h for steps taken, 4-2 h for time spent ground sniffing, frequency of standing up, pawing, circling and flanking, and 2-0 h for active and passive social interactions. The observed frequencies of a large number of two-event behavior sequences were found to deviate from their expected values during periods 4-2 and 2-0 h prepartum P<0.05). Most of the sequences occurring more frequently than expected involved either sniffing of other animals or restlessness in the preparturient ewe, but not both. Restlessness in the preparturient ewe involved either ground-directed investigation or self-directed behaviors and posture changes. Ground sniffing and circling frequently occurred in sequences with any of these general groupings of behavior. Lambing ewes were associated with significantly fewer penmates than expected during the final 2 h before parturition ( P<0.05). During the 12 h prepartum, there was a significant overall pattern for ewes and the group to move away from each other as lambing became imminent ( P<0.05).